Making speakers
Hi all. Look for some advice on speakers.
I use naim sbl with my seca amp and have found them bass light. As I put on a different pair of kef and the bass is much better but I think they lack in the mid.
I have a massive pair of transmission line from where I used to live but are to big for the room. I'd like to make a pair of floor or stand mount speakers with the units out off the transmission line.
Witch are kef b139 and a peerless mid and an addax tweeter.
Your thoughts please.
I use naim sbl with my seca amp and have found them bass light. As I put on a different pair of kef and the bass is much better but I think they lack in the mid.
I have a massive pair of transmission line from where I used to live but are to big for the room. I'd like to make a pair of floor or stand mount speakers with the units out off the transmission line.
Witch are kef b139 and a peerless mid and an addax tweeter.
Your thoughts please.
Comments
I'm surprised you find the SBLs bass light, they're certainly not rumblers but light?
MkI or MKII bass driver?
Yours from new or 2nd hand? (wondering about set up)
Maybe you could experiment on placement within your room, all the usuall parameters except; must be against a solid wall.
Improving on the standard Xover can also bring surprising dividends.
I would say the bass is there but is not very deep doesn't seem to go really low.
Having owned and installed many of these placement is really critical on them. Usually firing from the longer wall, if the room is not square. Not just "close" to the wall but as snug as you can get them, literally backs to the wall, as close as you can without actually touching, no toe in. In most rooms approx. 5.5' - 6' apart is the sweet spot. That wall must be solid, not partition etc.
I do agree they do not dig deep though, I suppose it depends on what you are used to and how deep you want (not to be confused with quantity of bass).
There is a chance that the bass driver box is not properly set up to the chamber below. That seal must be good and is easily compromised while moving the speakers. The spikes of said driver box must also rest on the small metal plates of the bass chamber, not pierce them.
I found mine had sufficient bass even for movie watching. However, I do dislike booming or prominent bass so maybe just different preferences?
I understand what you are saying with building speakers.it's very very difficult.
It may be an amp speaker match problem.
Colin made me the seca amp and what a brilliant job I love it. I was just surprised that I got more deep bass from a small speaker. And find the sbl's light. They were about deep when using a claymore.
Don't no what to try. Would standing them on the carpet be better the slate.
Can the crossovers be change to help this?
It's the crossover on these that give them the 6ohm rating, the drivers are 8ohm which is what the amps in an active system would see. As PAC said this dips in real usage.
When you purchased them were they re-set up properly (by you or by a dealer) or did you use them as they came?
I'm trying to narrow down a problem in the set up as I have also had a 15w Aclass amp (not SECA) replace a Claymore and I was both delighted and impressed with the resulting sound so am having problems thinking your problem is a simple mismatch.
If you do try standing them on the carpet be sure the spikes pierce to the floor below with the frame of the speakers just clear of the carpet.
In general, I've found that in general one needs large drivers to plumn the depths. Paul (RFC) seems to find ways around this with some of his designs, but outside of RFC towers, it's what I've generally found.
The SECA certainly goes low. I was impressed by how low it went with Colin's own standmounts, but we both remarked about how, on some tracks with deep / low bass the speakers simply couldn't do the SECA justice. At home with my old Goodmans (10/12 inch bass drivers) the SECA's bass came through far more impactfully.
In addition, I'll put up my hand here and say that I do have a subwoofer (built around an old 18 inch Goodmans driver in a huge sealed cab). Which is a bit silly as a SECA into large floorstanders is plenty for most tracks. The sub is something that I feel ambivalent about. On the positive side, I listen to a lot of dub and electro where deep deep bass is almost the whole point of the track. With the sub turned on I realise how subconsciously used I am (without the sub) to the lowest notes slightly fading away. It is an absolute delight with the sub turned on to have the volume of bass lines maintained throughout. Keith Hudson's "Blood Brother" on the "Pick a Dub" album is a good example of this. The lowest notes of the bass line are utterly incredible with the sub turned on. They don't budge an inch. Impossible not to smile and rub one's hand with excited glee.
On the downside, what people are saying about the timing is true. Or rather, I found it hard to get the timing right(ish). Before I introduced my sub I did a bit of reading (most of it beyond me). A few times I came across the notion that to work a sub into a system it is helpful if it is closer to the listening position than the main speakers, in order to reduce the likelihood of the wave from the sub from already being "behind" the wave form the main speakers before one starts to adjust the phase control on the sub amp. Most sub amps have a continuous "phase" control (0-180 degrees) which I think basically delays the signal to the set degree, in order to avoid the sound waves from the sub bring out of phase from the equivalent sound waves coming from the main speakers. The problem is that (obviously(?)) the phase control can only delay the signal from the subwoofer (it can't bring it forward (unless it contains time-travel circuitry). If the signal is already "behind" that from the main speakers (eg due to potentially longer / more convoluted signal paths in the sub pre- and power- amp) bringing the wave subjectively "in phase" may actually be resulting in the delaying of the overall note longer, and so messing with the timing further.
Sometimes I think I hear that a bit, even though the sub is tucked right behind my sofa. However, in my case the sub really is filling in the absolute lowest registers (probably picking to pick up things from about 40Hz down), so if there is a slight timing issue it's neither pronounced nor frequent. Also the amp I stuck in the sub is a fairly cheap one (good enough), so it maybe that the *quality* of the bass isn't as good as that coming out the mains.
Actually, for me the greater issue when fine tuning the sub was its physical position relative to my usual listening position. It took ages, but I'm happy with it now.
In any event, I don't have the sub on all the time. Only on tracks in which the deep bass is an integral part of the overall story.
How do you make them active.
As I don't realy want to sell the amp Colin as just made for me.
As I have no experince of solid state single ended I can't agree or disgaree with PAC's comments on compatability with your speakers, I can only repeat that my Aclass 15w (not single ended) worked beautifully on them.
On the bright side you'll have no trouble selling them, they are sought after second hand and being second hand to you originally you'll probably not lose out financially either.
UG, I share your non-fan status of Naim equipment in general but made an exception for the SBLs. They are now long gone, however. I run some smaller stand mounts at the moment.
I hope Colin's out and at them soon. I see John Farlowe (founder of Exposure) now also works with Naim equipment (Naim Thailand) !