Thanks GuysI’m pretty average with forum posting so the help is much
appreciated.
Hi Colin
Looks a little more like the SECA power amp which rocks. I have
a few headphone amps which I’ve used in the past as a Pre amp but some are
better than others in that regard.
Would it work as a pre?
How do I sign up for some boards?
The unique SECA design really pricked my interest and turns
out to sound superb so win, win for me but as Oliver said.
Can I have more please.
Well I believe firstly allowing DIY to choose their own PSU designs could be silly as I design things with PSU's to perform well.
Now PRE - AMP well to be blunt and honest the demand for SECA amp as not made it really worth my while to get involved with tooling cost and PCB left in stock the demand is far to low. I am actually out of pocket.
Now to put the circuit up and risk wrong builds on a complex circuits may not be such a good idea and vero is crap, track layout is critical and lots of attention must be used in the layout and component choice. And a few amatuer believe they have a better handle on this than my 40+ year experience has.
It like cable a change in dielectric and you have a cable but not a good cable and it has to be fit for purpose so 30 Amp cooker cable is not the answer for audio, but great for cookers.
So unless there are more interest forget it take time and money to do, and I am not in a good position after TQ to fund it.
Well I believe firstly allowing DIY to choose their own PSU designs could be silly as I design things with PSU's to perform well.
Now PRE - AMP well to be blunt and honest the demand for SECA amp as not made it really worth my while to get involved with tooling cost and PCB left in stock the demand is far to low. I am actually out of pocket.
Now to put the circuit up and risk wrong builds on a complex circuits may not be such a good idea and vero is crap, track layout is critical and lots of attention must be used in the layout and component choice. And a few amatuer believe they have a better handle on this than my 40+ year experience has.
It like cable a change in dielectric and you have a cable but not a good cable and it has to be fit for purpose so 30 Amp cooker cable is not the answer for audio, but great for cookers.
So unless there are more interest forget it take time and money to do, and I am not in a good position after TQ to fund it.
Sorry.
I can understand your position Colin, but it makes me sad. I am disappointed. :-L
Well I believe firstly allowing DIY to choose their own PSU designs could be silly as I design things with PSU's to perform well.
Now PRE - AMP well to be blunt and honest the demand for SECA amp as not made it really worth my while to get involved with tooling cost and PCB left in stock the demand is far to low. I am actually out of pocket.
Now to put the circuit up and risk wrong builds on a complex circuits may not be such a good idea and vero is crap, track layout is critical and lots of attention must be used in the layout and component choice. And a few amatuer believe they have a better handle on this than my 40+ year experience has.
It like cable a change in dielectric and you have a cable but not a good cable and it has to be fit for purpose so 30 Amp cooker cable is not the answer for audio, but great for cookers.
So unless there are more interest forget it take time and money to do, and I am not in a good position after TQ to fund it.
But please understand that I thought we were having a
conversation and my suggestion re the 83 was based on that. It’s difficult to
make that not look like me being a wise guy who knows best and TBH if I knew
more than you then you’d be building my amps and I’d be answering your
questions.
I’m a totally average kind of guy.
You may have noticed that I’m mostly DIY and feel a little
sad that great designs slide away un-noticed. That would in this case be a loss
for anyone who values innovation and thinking outside of the box which the SECA
obviously is.
OK on the SECA pre
TBH I’m as surprised as you are that the take up for the PA has
been lower than expected especially given the obvious sonic quality of the amp.
But given that fact then your obvious reluctance to stump up more cash is
totally understandable.
BTW the reason I suggested people find their own PSU as to
reduce your work load and nothing more than that. But I can understand that my
nudging you (a little) may have become irritating so I won’t mention it again
unless you do.
Funding
Well you come up with a circuit and board design and for a
small number of boards I can have them produced (which I’ve done before many
times for other DIY projects) and I’ll fund the production myself if necessary.
Or I’ll wait for a magnum pre to surface.
What’s the best way of collecting names of interested
parties? Here or a new thread?
"BTW the reason I suggested people find their own PSU as to reduce your work load and nothing more than that. But I can understand that my nudging you (a little) may have become irritating so I won’t mention it again unless you do."
Not irritating at all sorry you may have been mislead by my very poor writing skills.
I would love to it with ECC83 or even OC28 not a problem it just I am not in good health and I am not earning any pennies at all.
Sorry to hear of your health problems which must make the
work you do more difficult.
Relax and don’t give it another thought.
The thing for me is this.
I’ve done tubes of all sorts and really do like them but I’ve
not had the same sort of revelation that I’ve had with the SECA Mono’s for a
very long time. I’ve been around the block a few times and don’t make such
comments lightly.
It has an honesty and rightness to its sound which makes it
something special to my ears.
A rare beast.
Anything I can do to facilitate any future developments Pre wise just say the word.
Anyone foolish enough to part with their Magnum pre step forward and be known.
Sorry to hear of your health problems which must make the
work you do more difficult.
Relax and don’t give it another thought.
The thing for me is this.
I’ve done tubes of all sorts and really do like them but I’ve
not had the same sort of revelation that I’ve had with the SECA Mono’s for a
very long time. I’ve been around the block a few times and don’t make such
comments lightly.
It has an honesty and rightness to its sound which makes it
something special to my ears.
A rare beast.
Anything I can do to facilitate any future developments Pre wise just say the word.
Anyone foolish enough to part with their Magnum pre step forward and be known.
ATB
Nope! :P
I remain interested in a pre-amp build though, as Colin knows. :-\" The ID25 is supposed to be a good deal better than Magnum, but I couldn't persuade Paul Quick to sell me his! And I no longer have any money... (The TQ Listen is even rarer, and may even be better than the ID25 despite not being pure SECA - ask Colin).
I have a little pertinent experience to share;
My own SECA monoblocks, which pre-date one4audio, were built by Col and myself a few years ago (it's not a conventional amp at all, it has IGBT output devices instead of MOSFETS) - this was a project where I had PCBs and tooling made for these specific amps. We ordered very, very high quality double sided PCBs if I remember, and the all-in cost for PCBs and tooling came to about £250-ish. **
The thing is, Colin's pre-amps are (as he explained) much more critical to build, hence the use of surface mount parts and four layer PCBs (if I remember correct - Colin?) - the cost is even higher than my PCBs were. I would also assume the recent dynamic PSU cannot be altered to run a Pre, which would have simplified things a lot. Added to all this expense is the fact Colin doesn't make rubbish, so the parts are always quality, sometimes unusual and expensive, then there is the extra complexity of phonostages (I'd rather one without but Colin would rather build it in - and it's not really so simple to just make a slot in board - remember the PCB and tooling costs!) - so I can see where Colin is coming from.
I just wish things were different. Perhaps so I could afford to buy the real deal when it eventually makes it onto the market - that would be nice!! The painful thing is, I heard the previous SECA pre prototype about two or three years ago (in Colin's previous life) and it was EPIC! I cannot forget the damned thing. =P~
** I actually ordered 3x sets of mono boards as the extra costs were minimal after tooling and the initial costs - Colin has the other 2x sets if anyone is interested. Col christened it 'Brownium Motion Amplifier'. I'm sure Colin would build them up - either with IGBTs or FETS - if someone wanted a pair and it would obviously help out somewhat.
Sorry to hear of your health problems which must make the
work you do more difficult.
Relax and don’t give it another thought.
The thing for me is this.
I’ve done tubes of all sorts and really do like them but I’ve
not had the same sort of revelation that I’ve had with the SECA Mono’s for a
very long time. I’ve been around the block a few times and don’t make such
comments lightly.
It has an honesty and rightness to its sound which makes it
something special to my ears.
A rare beast.
Anything I can do to facilitate any future developments Pre wise just say the word.
Anyone foolish enough to part with their Magnum pre step forward and be known.
ATB
Nope! :P
I remain interested in a pre-amp build though, as Colin knows. :-\" The ID25 is supposed to be a good deal better than Magnum, but I couldn't persuade Paul Quick to sell me his! And I no longer have any money... (The TQ Listen is even rarer, and may even be better than the ID25 despite not being pure SECA - ask Colin).
I have a little pertinent experience to share;
My own SECA monoblocks, which pre-date one4audio, were built by Col and myself a few years ago (it's not a conventional amp at all, it has IGBT output devices instead of MOSFETS) - this was a project where I had PCBs and tooling made for these specific amps. We ordered very, very high quality double sided PCBs if I remember, and the all-in cost for PCBs and tooling came to about £250-ish. **
The thing is, Colin's pre-amps are (as he explained) much more critical to build, hence the use of surface mount parts and four layer PCBs (if I remember correct - Colin?) - the cost is even higher than my PCBs were. I would also assume the recent dynamic PSU cannot be altered to run a Pre, which would have simplified things a lot. Added to all this expense is the fact Colin doesn't make rubbish, so the parts are always quality, sometimes unusual and expensive, then there is the extra complexity of phonostages (I'd rather one without but Colin would rather build it in - and it's not really so simple to just make a slot in board - remember the PCB and tooling costs!) - so I can see where Colin is coming from.
I just wish things were different. Perhaps so I could afford to buy the real deal when it eventually makes it onto the market - that would be nice!! The painful thing is, I heard the previous SECA pre prototype about two or three years ago (in Colin's previous life) and it was EPIC! I cannot forget the damned thing. =P~
** I actually ordered 3x sets of mono boards as the extra costs were minimal after tooling and the initial costs - Colin has the other 2x sets if anyone is interested. Col christened it 'Brownium Motion Amplifier'. I'm sure Colin would build them up - either with IGBTs or FETS - if someone wanted a pair and it would obviously help out somewhat.
Alan they are your PCB I will not use them just keep them safe until I meet Old Harry soon.
I'd have loved to build a set of these but the £hobby pot is rather sad at the moment. If you still have a spare set of boards come spring time I could relieve of of them then, along with PSU boards.
If a pre-amp with phono stage happens I'm definitely interested, the funds will stretch to that if I make my own chassis.
Col, What is the maximum wattage these powers can be run up to? More power Scotty, I need more power! (I'm a bit of a maniac with the volume control ) :-\"
CJ, mine run at 27 man-watts. Because the 2 giant IGBT output devices on each amp run so hot they are unusual, but if I had painted my heat-sinks black 30 watts would have been no problem.
Convert the 'Brownium Motion' circuit board to run multiple, smaller FETs (easy, according to Col) and I expect 35 watts would be do-able, and the dynamic PSU works with these.
I remember you posted a graph but I couldn't find it
I don't realy understand the heat dissipation to size of heatsink thing, Would they be bigger than the chunky cube-like ones shown on the mono builds or 2 of those per mono? (these and the case are the main reason for holding back for costs)
James, there are 2 x pairs of boards mate. Colin has them all, he doesn't want to use them because I paid to have them made - but I won't be needing them! (I'd like to build a pre-amp, and maybe a one4 kit, with the kids in the future).
As far as I am concerned they're available (especially if they aid your recovery), I'm sure Colin can build them easily for you. Over to you, Col!
Yes I may have seen your build when researching my SECA
efforts. Brownian motion well how cool is that.
And the explanation on the complexities of creating a new
pre board was enlightening. Not by any means a trivial task.
Those boards on offer look really tempting but others have
been here longer so I’ll take a pass.
TBH one of the things that really attracted me to the simple
SECA build was the regulated PSU add on and the overall attention to detail. I’m
also young enough to remember some of Colin’s other work.
Chris
We’ve done a simple reg for a low power Class A before and
it can make a big difference to the sound, better or worse. You may be good for
the simple SECA and go large on the sinks and heavier on the bias (or some new
speakerrrrs). Think that you may be a
little surprised at the SPL that can be had from it.
The Dynamic PSU really lifts the SQ nicely to my ears without
descending into the sort of Greyness that some regs seem to bring along with
the detail.
I’ve heard that sort of improvement once before with my choke
plate 76-45 which Nick helped me with many years ago.
Adding a simple 6080 based linear reg to the B+ on that baby
really made her sing.
Maybe low power, tightly reg’d amps have life in em yet. Glass
or Sand.
But as they say
That was then and this is now where sand holds my interest
more.
...demand for SECA amp as not made it really worth my while to get involved with tooling cost and PCB left in stock the demand is far to low. I am actually out of pocket.
What's wrong with this bloody world / dimension / reality... where this is part of it...? I feel a strong sense of injustice. Purely on merit, you and your product deserve better.
Part of the problem may be the one that afflicts quite a few
‘’NEW’’ diy products.
We have the classic chicken and egg.
People (myself included) tend to be sceptical about new
things (not a new circuit but new DIY wise) and may shy away from a build if
they have not heard it.
People struggle to find a place to listen without doing the
build themselves first and then it’s fingers crossed that you like what you
have made.
The best way to get some exposure is to do the bake offs and
‘’DIY orientated meet ups’’ so that people can make an assessment with their own
ears.
I have heard Some of colins work before so the leap of faith
was not so big but I still hovered around this build for a while.
Others may not be quite so familiar with the TOCA, SECA,
Claymore and such like so it really does require a big leap.
With commercial stuff it’s actually easier.
You go through the review process (mags and on line) and
then on to a dealer for a listen and then purchase if happy.
With DIY it’s a little hit and hope and even though the SECA
is great VFM IMHO it’s still a large enough outlay to make for careful thought.
I’ve bought loads of really average stuff on the basis of
the thoughts of ‘’others’’ so I can understand why people can be reluctant.
Sooooo
Let’s have a target list of shows/meet ups and If anyone is
interested in a little payback for Mr C lets make it happen.
Funnily enough, I'd been thinking along similar lines.
I agree. We need to get these amps out there.
Is there a Pie Fi show this year? If so, is anyone taking a SECA along?
And bake-offs? Absolutely.
I thought I hated Class A amps, until Colin brought round an Iridium when he was at TQ. That did it. I had to have one of these SECAs.
I also need to get back on to the Wiki I've started here to lay out the information we have about the amps and building them in a more digestible form.
When he first talked about the kits, I suggested to Colin that we made some videos showing how to put the amps together to try to eradicate some of the doubts - can I make some of these things?
I'm at the pie fi show this year but I've not finished my SECA build yet - only need to mount the boards and wire it up though. Got to decide whether to finish that and take it along, or take my Audio Note or EAR amps. I told myself I'd never own more than one of the same item X_X
I have them running @7V with those little Maplin’s Linear
PSU’s and they are indeed very quiet fanning the sink fins.
Makes a big difference heat wise with the sinks running luke
warm rather than hot @ 2.1A which is nice and should allow a little more bias
current to be used.
Next step is to find a way of switching them on when the
sinks reach 50 deg or so.
The fans seem to be doing their stuff
pretty well and a resulting discussion over on PFM may have provided them with
basic temperature control curtesy of PD.
‘’There are plenty of water cooling kits available for PCs, but I know what
you mean’’.
Just a touch of Hydrophobia on my part.
‘’Looks like things are moving forward for you. Gratifying to see how
people pitch in with ideas.’’
Yup it’s what makes DIY such fun and one person helping another is the
special part. We all become better at what we do and then pass it on to others.
Group learning.
One thing that I have not checked is what happens to the
bias with the fan on and the sinks running cool.
I have the thermistor fitted as per Colin’s instructions
(auto bias) and if I have it right then the bias may have gone up a little
because the sinks are never reaching 50 deg.
‘’Looks like things are moving forward for you. Gratifying to see how
people pitch in with ideas.’’
Yup it’s what makes DIY such fun and one person helping another is the
special part. We all become better at what we do and then pass it on to others.
Group learning.
I was able to complete my build only with the help of people here, and Colin of course! I felt very accompanied. Which was uexpectedly wonderful, as I assumed / dreaded that I would be all alone.
On the subject of combining electricity and water, I believe Colin has done something like this during testing (I seem to remember his mentioning it).
My utility supplier keeps encouraging me to combine my electricity and gas. Which always sounds very dangerous to me*... :P
‘’Looks like things are moving forward for you. Gratifying to see how
people pitch in with ideas.’’
Yup it’s what makes DIY such fun and one person helping another is the
special part. We all become better at what we do and then pass it on to others.
Group learning.
I was able to complete my build only with the help of people here, and Colin of course! I felt very accompanied. Which was uexpectedly wonderful, as I assumed / dreaded that I would be all alone.
On the subject of combining electricity and water, I believe Colin has done something like this during testing (I seem to remember his mentioning it).
My utility supplier keeps encouraging me to combine my electricity and gas. Which always sounds very dangerous to me*... :P
‘’Looks like things are moving forward for you. Gratifying to see how
people pitch in with ideas.’’
Yup it’s what makes DIY such fun and one person helping another is the
special part. We all become better at what we do and then pass it on to others.
Group learning.
I was able to complete my build only with the help of people here, and Colin of course! I felt very accompanied. Which was uexpectedly wonderful, as I assumed / dreaded that I would be all alone.
On the subject of combining electricity and water, I believe Colin has done something like this during testing (I seem to remember his mentioning it).
My utility supplier keeps encouraging me to combine my electricity and gas. Which always sounds very dangerous to me*... :P
* Joke credit: Lee Mack.
Yes
I remember watching your build take shape and thinking what a great job you'd done.
‘’Looks like things are moving forward for you. Gratifying to see how
people pitch in with ideas.’’
Yup it’s what makes DIY such fun and one person helping another is the
special part. We all become better at what we do and then pass it on to others.
Group learning.
I was able to complete my build only with the help of people here, and Colin of course! I felt very accompanied. Which was uexpectedly wonderful, as I assumed / dreaded that I would be all alone.
On the subject of combining electricity and water, I believe Colin has done something like this during testing (I seem to remember his mentioning it).
My utility supplier keeps encouraging me to combine my electricity and gas. Which always sounds very dangerous to me*... :P
* Joke credit: Lee Mack.
Yes
I remember watching your build take shape and thinking what a great job you'd done.
An inspiration to others.
Yep Ben did bloody well great job for the first time.
Yes if you cool the heatsink the bias does go up, and the amp damping factor goes up too , giving more control and amazing bass, so turn the central heating off open all the windows and enjoy the music, I do Br Br Br BRRRR Br Br Br see easy better than La La La LAAAA La La La
I thought that the amp sounded more spacious with better
bass control but wanted the measurement just to confirm that errrr something
had changed. Not that measurement tells all but just to know for sure.
I'm shocked by the efficiency of a 120mm fan gently
blowing on the sink.
Makes me really tempted to just leave the fans spinning when
the amps are on and crank the bias up a little further.
My workshop/music room/person cave is pretty cool this time
of year but even with the heating on and the fans blowing the sinks stay pretty
cool.
2.5A looks good and easily do-able with the fans.
I’ll crank up the heating to summer tempratures and give it
a go.
2 x cheap quiet fans and PSU sound like a good upgrade.
All working well but now I need to think a little harder about getting the temperature setup for best performance given that the sink temp can be dialled in in a rough and ready way.
of course with this sort of fan control arrangement the temperature is going to be relatively stable (but not linear) which will help especially in the summer.
I'm going to heat the room to 30deg (oooooh lovely) and maybe apply 10 deg above ambient for starters.
I remember watching your build take shape and thinking what a great job you'd done.
An inspiration to others.
Well that's pleasing to read. Many thanks. A little humbling too, coming from you!
Reading about your current efforts to keep your amp cool, I'm wondering if there is an optimum / recommended running temperature for these things...? The One4 SECA's heatsinks (just amp boards attached) run significantly cooler than do those of the TOCA 20 (which is almost too hot to touch).
I'm really just seeking reassurance re. the PSU boards. When I fitted the PSU boards, Colin reassured me that attaching them to the base plate would be sufficient for heat dissipation. This I did. Colin's word should be sufficient, but as I'm prone to anxiety and OCD, I'm checking... I've noticed that the baseplate, just where the PSU boards are fitted, gets pretty hot after running for a while. I can hold my finger against its warmest point for about 5 seconds before it feels uncomfortably warm / hot. (Probably not as hot as the TOCA 20 heatsinks, but warmer than the heatsinks one One4 SECA itself.) The heat does seem to dissipate quite quickly as it spreads across the baseplate of the One4 SECA - the baseplate is merely slightly warm by the time the heat energy reaches its edges. I am assuming that this dissipation pattern is OK for the One4 Seca...?
Sounds great. BTW! Spent a short while listening to the Claymore -> Warfdale XP3s in the 2nd system this morning, and tbh was more disappointed than I wanted to be with the sound coming from the 2nd session in comparison with the One4 SECA -> RFC/Goodmans Goodwoods. I'm back with the main rig now. Really appreciating what I've got today. :-)
The PSU should only dissipate about (2.5A * 7V) *2 =35W max compared to the amp 2.5A * 40V = 100W max for one channel only.
Lets assume 1W on 1 square inch will rise 20C above ambient (rule of thumb) you can do the rest for the base plate.
This is a rough guide and does depend on air flow etc and not resting on carpet or cat, or warming slippers Alan.
This is reassuring I think Colin! Thank you.
Although I'm not sure what the implications of the "1W on 1 square inch will rise 20C above ambient" in the context of the PSU putting out 35W... Ie, I don't think the base plate, at its hottest spot (ie where its touching the PSU plate) gets more than 40C above ambient (that is an utter guess based on my thurmbometer).
Occasionally my cat uses the top of the amp. It is a preferable alternative (for me) to his sitting on the media PC, which he is more likely to overheat when he sits on the air vents above its internal heat sink...! 8-X He is quite well trained now. All I need to do is sternly call his name if he gets on the TFS and he shuffles over to the SECA...
No way different yes better no, The Claymore is great for rock and parties and very good loud but the SECA wins on detail and finesse. You should have heard the 100W/ch last week around Alan's wow what a beaut, power finesse and so quiet it was dark between base notes and a little scary. The awesome power was amazing but it was getting late so not pushed too hard.
Oh this will not be a kit ever it is so complex I had a headache after building just six PCB,s it took over a week to do each PCB and each amp has two, all parts must be matched.
Can't wait to build another set , the first two are already sold and are going into a Bi-Amp system.
No way different yes better no, The Claymore is great for rock and parties and very good loud but the SECA wins on detail and finesse. You should have heard the 100W/ch last week around Alan's wow what a beaut, power finesse and so quiet it was dark between base notes and a little scary. The awesome power was amazing but it was getting late so not pushed too hard.
Oh this will not be a kit ever it is so complex I had a headache after building just six PCB,s it took over a week to do each PCB and each amp has two, all parts must be matched.
Can't wait to build another set , the first two are already sold and are going into a Bi-Amp system.
Personally I prefer the SECA over the Claymore. The Claymore is the best integrated and non-CLass A amp I've owned, and I love it very much, but for me your One4 amp is in every way sonically preferable to the Claymore. And I will fight you, bare knuckle and bare chested, to prove how much I care about that. The Claymore may well go louder!
‘’This I did. Colin's word should be sufficient, but as I'm prone to
anxiety and OCD, I'm checking...’’
Then you have good personality trait for DIY. Welcome to the OCD DIY club I’ll
show you around when I have a little time.
I’ve found that my SECA ran a little cooler in use with the PSU fitted TBH.
The PSU seems to run pretty cool and its place on my heat sink is the last to
heat up. From memory your cases have 3mm Ali base and top plate and are a nice
luxury to have. The heat you describe seems pretty normal IMHO and I’d have
mounted my own PSU that way if it were not for the steel frying pans that I have
as errrrummm bases at the moment.
‘’A little humbling too, coming from you!’’
No not at all. Your build proves what can be done with effort and some know
how from the guys here. I’m a bit of an old hand but I’d have panicked at the
thought of this build when I first started.
What’s even more pleasing is that you’ve built something WORTH HAVING
without going through all of the crap projects that are out there in abundance.
I’ve found that my SECA ran a little cooler in use with the PSU fitted TBH.
The PSU seems to run pretty cool and its place on my heat sink is the last to
heat up. From memory your cases have 3mm Ali base and top plate and are a nice
luxury to have. The heat you describe seems pretty normal IMHO and I’d have
mounted my own PSU that way if it were not for the steel frying pans that I have
as errrrummm bases at the moment.
Thanks for the reassurance. I'm feeling even happier that everything's OK.
And, that's interesting. Mine runs ever so slightly warmer. I think. You're right: Yes, a 3mm base plate. It's fairly substantial.
No not at all. Your build proves what can be done with effort and some know
how from the guys here. I’m a bit of an old hand but I’d have panicked at the
thought of this build when I first started.
What’s even more pleasing is that you’ve built something WORTH HAVING
without going through all of the crap projects that are out there in abundance.
That is a bonus, definitely! :-) I didn't expect it to turn out better than the TOCA20. That was my ignorance. It's turned out to be a real keeper. I really can't overstate how practically and emotionally significant the "know how from the guys" was. I was very nervous. I think the certainty I had that, due to my previous personal experience of the man, if I had a total failure then Colin would definitely help me if I could get the amp to him was a safety net that pushed me forward. The help from others (e.g. Paul Quick) was an unexpected and uplifting bonus. :-)
Comments
Thanks GuysI’m pretty average with forum posting so the help is much appreciated.
Hi Colin
Looks a little more like the SECA power amp which rocks. I have a few headphone amps which I’ve used in the past as a Pre amp but some are better than others in that regard.
Would it work as a pre?
How do I sign up for some boards?
The unique SECA design really pricked my interest and turns out to sound superb so win, win for me but as Oliver said.
Can I have more please.
(probably not so disappointed as yourself)
No need to be sorry for anything.
But please understand that I thought we were having a conversation and my suggestion re the 83 was based on that. It’s difficult to make that not look like me being a wise guy who knows best and TBH if I knew more than you then you’d be building my amps and I’d be answering your questions.
I’m a totally average kind of guy.
You may have noticed that I’m mostly DIY and feel a little sad that great designs slide away un-noticed. That would in this case be a loss for anyone who values innovation and thinking outside of the box which the SECA obviously is.
OK on the SECA pre
TBH I’m as surprised as you are that the take up for the PA has been lower than expected especially given the obvious sonic quality of the amp. But given that fact then your obvious reluctance to stump up more cash is totally understandable.
BTW the reason I suggested people find their own PSU as to reduce your work load and nothing more than that. But I can understand that my nudging you (a little) may have become irritating so I won’t mention it again unless you do.
Funding
Well you come up with a circuit and board design and for a small number of boards I can have them produced (which I’ve done before many times for other DIY projects) and I’ll fund the production myself if necessary.
Or I’ll wait for a magnum pre to surface.
What’s the best way of collecting names of interested parties? Here or a new thread?
Thanks for the honesty of your previous post.
It’s appreciated.
Hi Colin
Sorry to hear of your health problems which must make the work you do more difficult.
Relax and don’t give it another thought.
The thing for me is this.
I’ve done tubes of all sorts and really do like them but I’ve not had the same sort of revelation that I’ve had with the SECA Mono’s for a very long time. I’ve been around the block a few times and don’t make such comments lightly.
It has an honesty and rightness to its sound which makes it something special to my ears.
A rare beast.
Anything I can do to facilitate any future developments Pre wise just say the word.
Anyone foolish enough to part with their Magnum pre step forward and be known.
ATB
Nope! :P
I remain interested in a pre-amp build though, as Colin knows. :-\" The ID25 is supposed to be a good deal better than Magnum, but I couldn't persuade Paul Quick to sell me his! And I no longer have any money... (The TQ Listen is even rarer, and may even be better than the ID25 despite not being pure SECA - ask Colin).
I have a little pertinent experience to share;
My own SECA monoblocks, which pre-date one4audio, were built by Col and myself a few years ago (it's not a conventional amp at all, it has IGBT output devices instead of MOSFETS) - this was a project where I had PCBs and tooling made for these specific amps. We ordered very, very high quality double sided PCBs if I remember, and the all-in cost for PCBs and tooling came to about £250-ish. **
The thing is, Colin's pre-amps are (as he explained) much more critical to build, hence the use of surface mount parts and four layer PCBs (if I remember correct - Colin?) - the cost is even higher than my PCBs were. I would also assume the recent dynamic PSU cannot be altered to run a Pre, which would have simplified things a lot. Added to all this expense is the fact Colin doesn't make rubbish, so the parts are always quality, sometimes unusual and expensive, then there is the extra complexity of phonostages (I'd rather one without but Colin would rather build it in - and it's not really so simple to just make a slot in board - remember the PCB and tooling costs!) - so I can see where Colin is coming from.
I just wish things were different. Perhaps so I could afford to buy the real deal when it eventually makes it onto the market - that would be nice!! The painful thing is, I heard the previous SECA pre prototype about two or three years ago (in Colin's previous life) and it was EPIC! I cannot forget the damned thing. =P~
** I actually ordered 3x sets of mono boards as the extra costs were minimal after tooling and the initial costs - Colin has the other 2x sets if anyone is interested. Col christened it 'Brownium Motion Amplifier'. I'm sure Colin would build them up - either with IGBTs or FETS - if someone wanted a pair and it would obviously help out somewhat.
They are available anyway!
If a pre-amp with phono stage happens I'm definitely interested, the funds will stretch to that if I make my own chassis.
Col,
What is the maximum wattage these powers can be run up to? More power Scotty, I need more power!
(I'm a bit of a maniac with the volume control ) :-\"
Convert the 'Brownium Motion' circuit board to run multiple, smaller FETs (easy, according to Col) and I expect 35 watts would be do-able, and the dynamic PSU works with these.
I don't realy understand the heat dissipation to size of heatsink thing, Would they be bigger than the chunky cube-like ones shown on the mono builds or 2 of those per mono? (these and the case are the main reason for holding back for costs)
As far as I am concerned they're available (especially if they aid your recovery), I'm sure Colin can build them easily for you. Over to you, Col!
Hi Alan
Yes I may have seen your build when researching my SECA efforts. Brownian motion well how cool is that.
And the explanation on the complexities of creating a new pre board was enlightening. Not by any means a trivial task.
Those boards on offer look really tempting but others have been here longer so I’ll take a pass.
TBH one of the things that really attracted me to the simple SECA build was the regulated PSU add on and the overall attention to detail. I’m also young enough to remember some of Colin’s other work.
Chris
We’ve done a simple reg for a low power Class A before and it can make a big difference to the sound, better or worse. You may be good for the simple SECA and go large on the sinks and heavier on the bias (or some new speakerrrrs). Think that you may be a little surprised at the SPL that can be had from it.
The Dynamic PSU really lifts the SQ nicely to my ears without descending into the sort of Greyness that some regs seem to bring along with the detail.
I’ve heard that sort of improvement once before with my choke plate 76-45 which Nick helped me with many years ago.
Adding a simple 6080 based linear reg to the B+ on that baby really made her sing.
Maybe low power, tightly reg’d amps have life in em yet. Glass or Sand.
But as they say
That was then and this is now where sand holds my interest more.
I’ll say DAC now just to get it out of the way.
I feel a strong sense of injustice.
Purely on merit, you and your product deserve better.
Hi Guys
THE THOUGHTS OF CHAIRMAN ERRRR SHAUN
DIY is a funny world.
Part of the problem may be the one that afflicts quite a few ‘’NEW’’ diy products.
We have the classic chicken and egg.
People (myself included) tend to be sceptical about new things (not a new circuit but new DIY wise) and may shy away from a build if they have not heard it.
People struggle to find a place to listen without doing the build themselves first and then it’s fingers crossed that you like what you have made.
The best way to get some exposure is to do the bake offs and ‘’DIY orientated meet ups’’ so that people can make an assessment with their own ears.
I have heard Some of colins work before so the leap of faith was not so big but I still hovered around this build for a while.
Others may not be quite so familiar with the TOCA, SECA, Claymore and such like so it really does require a big leap.
With commercial stuff it’s actually easier.
You go through the review process (mags and on line) and then on to a dealer for a listen and then purchase if happy.
With DIY it’s a little hit and hope and even though the SECA is great VFM IMHO it’s still a large enough outlay to make for careful thought.
I’ve bought loads of really average stuff on the basis of the thoughts of ‘’others’’ so I can understand why people can be reluctant.
Sooooo
Let’s have a target list of shows/meet ups and If anyone is interested in a little payback for Mr C lets make it happen.
I’d be willing to lend a hand.
I've been to the ones at egg borough Power Station but its newer version looks good.
Owston
http://simonsnewadventuresinhifi.blogspot.co.uk/2013/12/audio-meet-owston-9th-and-10th-november.html
Solid DIY, Anyone can bring and play (no pre booking or any of that stuff). With good friendly people who know their stuff.
NE Bake-Off is another good spot but a little far for the southerners (or mid landers).
Most of the really good DIY stuff happens in a way that makes the shows look pretty stiff and average.
My SECA is still semi naked so I'll need to pull my finger out on the chassis.
(...and i'm just a bit further down the road in Gloucester.)
And onwards to stage 2
The fan dance
I’ve been playing with a pair of these
http://www.ebay.co.uk/itm/111880558708?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I have them running @7V with those little Maplin’s Linear PSU’s and they are indeed very quiet fanning the sink fins.
Makes a big difference heat wise with the sinks running luke warm rather than hot @ 2.1A which is nice and should allow a little more bias current to be used.
Next step is to find a way of switching them on when the sinks reach 50 deg or so.
Sounding superb
time to crank the bias up a little more
The fans seem to be doing their stuff pretty well and a resulting discussion over on PFM may have provided them with basic temperature control curtesy of PD.
http://www.pinkfishmedia.net/forum/showthread.php?t=179305&page=17
water and electronics I’m sure can be safe but makes me nervous.
Let’s see how it works out.
‘’There are plenty of water cooling kits available for PCs, but I know what you mean’’.
Just a touch of Hydrophobia on my part.
‘’Looks like things are moving forward for you. Gratifying to see how people pitch in with ideas.’’
Yup it’s what makes DIY such fun and one person helping another is the special part. We all become better at what we do and then pass it on to others.
Group learning.
One thing that I have not checked is what happens to the bias with the fan on and the sinks running cool.
I have the thermistor fitted as per Colin’s instructions (auto bias) and if I have it right then the bias may have gone up a little because the sinks are never reaching 50 deg.
Running luke warm
Worth looking at maybe.
It’s sounding really good this end.
I’ll keep you posted.
I felt very accompanied. Which was uexpectedly wonderful, as I assumed / dreaded that I would be all alone.
On the subject of combining electricity and water, I believe Colin has done something like this during testing (I seem to remember his mentioning it).
My utility supplier keeps encouraging me to combine my electricity and gas. Which always sounds very dangerous to me*...
:P
* Joke credit: Lee Mack.
Interesting
I thought that the amp sounded more spacious with better bass control but wanted the measurement just to confirm that errrr something had changed. Not that measurement tells all but just to know for sure.
I'm shocked by the efficiency of a 120mm fan gently blowing on the sink.
Makes me really tempted to just leave the fans spinning when the amps are on and crank the bias up a little further.
My workshop/music room/person cave is pretty cool this time of year but even with the heating on and the fans blowing the sinks stay pretty cool.
2.5A looks good and easily do-able with the fans.
I’ll crank up the heating to summer tempratures and give it a go.
2 x cheap quiet fans and PSU sound like a good upgrade.
Sounding superb this end.
A little humbling too, coming from you!
Reading about your current efforts to keep your amp cool, I'm wondering if there is an optimum / recommended running temperature for these things...?
The One4 SECA's heatsinks (just amp boards attached) run significantly cooler than do those of the TOCA 20 (which is almost too hot to touch).
I'm really just seeking reassurance re. the PSU boards. When I fitted the PSU boards, Colin reassured me that attaching them to the base plate would be sufficient for heat dissipation. This I did. Colin's word should be sufficient, but as I'm prone to anxiety and OCD, I'm checking... I've noticed that the baseplate, just where the PSU boards are fitted, gets pretty hot after running for a while. I can hold my finger against its warmest point for about 5 seconds before it feels uncomfortably warm / hot. (Probably not as hot as the TOCA 20 heatsinks, but warmer than the heatsinks one One4 SECA itself.) The heat does seem to dissipate quite quickly as it spreads across the baseplate of the One4 SECA - the baseplate is merely slightly warm by the time the heat energy reaches its edges. I am assuming that this dissipation pattern is OK for the One4 Seca...?
Sounds great. BTW! Spent a short while listening to the Claymore -> Warfdale XP3s in the 2nd system this morning, and tbh was more disappointed than I wanted to be with the sound coming from the 2nd session in comparison with the One4 SECA -> RFC/Goodmans Goodwoods. I'm back with the main rig now. Really appreciating what I've got today. :-)
But, it's impossible to get away from the fact that a SECA amp is better than a very decent Claymore!
Although I'm not sure what the implications of the "1W on 1 square inch will rise 20C above ambient" in the context of the PSU putting out 35W... Ie, I don't think the base plate, at its hottest spot (ie where its touching the PSU plate) gets more than 40C above ambient (that is an utter guess based on my thurmbometer).
Occasionally my cat uses the top of the amp. It is a preferable alternative (for me) to his sitting on the media PC, which he is more likely to overheat when he sits on the air vents above its internal heat sink...! 8-X
He is quite well trained now. All I need to do is sternly call his name if he gets on the TFS and he shuffles over to the SECA...
The 100W SECA sounds simply wonderful.
‘’This I did. Colin's word should be sufficient, but as I'm prone to anxiety and OCD, I'm checking...’’
Then you have good personality trait for DIY. Welcome to the OCD DIY club I’ll show you around when I have a little time.
I’ve found that my SECA ran a little cooler in use with the PSU fitted TBH. The PSU seems to run pretty cool and its place on my heat sink is the last to heat up. From memory your cases have 3mm Ali base and top plate and are a nice luxury to have. The heat you describe seems pretty normal IMHO and I’d have mounted my own PSU that way if it were not for the steel frying pans that I have as errrrummm bases at the moment.
‘’A little humbling too, coming from you!’’
No not at all. Your build proves what can be done with effort and some know how from the guys here. I’m a bit of an old hand but I’d have panicked at the thought of this build when I first started.
What’s even more pleasing is that you’ve built something WORTH HAVING without going through all of the crap projects that are out there in abundance.
They don’t call you lucky Doc for nothing.
Cool and calm work.
It’s so nice to see someone new coming through.
Thanks for the reassurance. I'm feeling even happier that everything's OK.
And, that's interesting. Mine runs ever so slightly warmer. I think.
You're right: Yes, a 3mm base plate. It's fairly substantial.
That is a bonus, definitely! :-)
I didn't expect it to turn out better than the TOCA20. That was my ignorance. It's turned out to be a real keeper.
I really can't overstate how practically and emotionally significant the "know how from the guys" was. I was very nervous. I think the certainty I had that, due to my previous personal experience of the man, if I had a total failure then Colin would definitely help me if I could get the amp to him was a safety net that pushed me forward. The help from others (e.g. Paul Quick) was an unexpected and uplifting bonus. :-)