diy amp builds

chrisb

With a few members building amps based on Colin's seca i would be interested in their thoughts regard boutique parts and the potential effect on sound quality. I have my 20w back now and after the transport mishap it was recapped with elna silmic uprated caps . These have a 100 to 200 hour run in period so mine  have a way to go before a proper evaluation can be done from memory of course. What interests me is can my amp be improved with uprated parts and cable etc. When one looks at the likes of audionote and their basic circuit being enhanced with boutique parts silver cable and the like is it worth it or balls. 

Chris 

uglymusic

Col?

Colin

Col?

Yes Dave?

If you have the money and time it can be worth it.

chrisb

Ah so which are the most important areas to be looked at out of interest.

Colin

R,s C,s SEMI,s Wire, Plastic box (no NVA parts), All parts it is just cost, even PCB layout. (note not direct wire crap)

uglymusic

So you're saying, the more you spend, the more you get out?

Colin

No you have to be very careful  to match parts, this takes time and experience or pure luck.

A cost of a part does not always bring a promise of a good sound.

But with experience and the ability to understand the Data sheet in relationship with other parts often brings very good returns.

In some circuit configurations a 10uF/50V Maplin capacitor costing 10p could sound very good. But in other circuit with the same design format a £20 10uf/200V Poly-carbonate just out performs it. It all to do with what is around it, the word "synergy" comes to mind, but we normally associated this with working completed products interacting with each other including cables.

All this takes time to learn and building more than one circuit design, and siting on a design for 30yrs and demanding it is the best, is just crap, for the self deluded. 

chrisb

Think cost no object would mean best resistors, caps, transformers and so on so, with a commercial product the line has to be drawn somewhere. The margin between that and chucking cash at it could be minimal ?Having never had the chance to hear the difference it would be interesting. Experience  as with anything counts for everything. 

quickie

I find choosing the nicest color seems to work well.

The samwha WF are lovely !

chrisb

Colin

So true Paul, Black Acrylic I found produced the nicest smoke.

quickie

Flappy plastic...........its fantastic

uglymusic

Look, chaps, I know Chews is famous for epic thread drift (and of course, we value it), but shall we help Chris with his question? :-)

Alan

I think Colin has covered the question very well. In the case of my own project experiences, I have only this to add:

To start, the design is different to the ID25. For one thing the power supply capacitors are not mounted on the PCB in my case. I had some large, very good (though apparently overpriced) capacitors from a previous project which were installed, Colin said these would provide very good bass (I think we measured the amp as -3dB at 5hz during setup). But we could have done as well or better for less money, we only used Kendeils because I already had them.

However, he made me sell my Avondale full wave bridge rectifiers I had bought at £50 a go because they were unsuitable in this circuit, in place of something much cheaper more widely available. Not boutique at all in fact. As the man says, it's about how well you (or in my case, someone else) understands the circuit and then using the most appropriate part, not the most expensive.

Elsewhere on the circuit, the specification was mostly for very high, even over-specced components. In other places Col was happy for an appropriate cheaper part to be used as it would usually perform in that application better than anything else (I especially liked the ingenious voltage regulators at under a pound each).

I would have loved to put in really top end transformers and internal TQ wiring loom etc etc, but the gains could end up being minimal for the amount it would cost (it would have doubled the cost of the project). I already have one of the finest sounding amplifiers around so I'm not going to worry about it. You are probably in a similar situation.

My 'baby blob' SECA is another amplifier, only 10W, was made out of old scrap parts and hammerite (it really looks like it should be installed in an early Land rover defender), and it saw off an NVA statement stereo amplifier easily. It was made of scrap parts. So I don't think boutique components are anything to fret about.

Alan

Just as an aside, my Magnum pre amplifier needed re-capping a couple of years back, so it got 'better' capacitors (Vishay, I think). But as it was out of spec before I started, I couldn't tell if the vast improvements were down to better components or just being back to factory spec. I think the lesson here is look for cost effective upgrades if you have to take it apart, otherwise don't worry about it. Be happy!

A far greater improvement came later when Colin performed a little upgrade (it took all of two minutes), which definately did not involve fitting boutique parts.

Later on, I rewired the volume pots & selector switched with TQ wire (I had a very sort set of black cables with I cannibalized), and I think I noticed a difference. It wasn't night & day though.

But in it's final form, Maggie wipes the floor with my previous Lightspeed LDR pre, so it all added up to something.

uglymusic

So the answer is 'you have to suck it and see'.

A more expensive component may not guarantee a better sound.

chrisb

My point initially, just makes you wonder when someone has 4-5 different variants of the same amp for example a basic and then the foo components. Blow your cash people

quickie

Its all about balance and knowing what to replace. Expensive does not allways equal better........

uglymusic

My point initially, just makes you wonder when someone has 4-5 different variants of the same amp for example a basic and then the foo components. Blow your cash people

That's not to say that the ones with the foo components aren't better.

The manufacturer/designer may have done their homework. 

You're down to having to trust your own ears and whether you also trust the manufacturer/designer.