advertisement


ATC Speakers and Naim amps

halvis

halvis

pfm Member
Just wanted to dispel a forum myth.

I have used ATC speakers for about 5 years now. I have tried many amps with varying degrees of success.

I currently use the Michell Alecto Monoblocks, which I am pretty happy with.

This week a friend wanted to borrow my amps, so he loaned me his Nait XS. I wasn't expecting much.

However, as long as you are not wanting to blow the windows out, this amp is very capable at driving probably the most difficult to drive passive ATC speakers - SCM 20 SL's. The midrange is particularly special and as long as the volume is not too loud, but still up around 85db easily, the bass line keeps up too.

The sound is not as 'big' as with my Alecto's, but the inner detail is very nice with perhaps the odd high becoming a little hard, again with increased volume. Of course, ATC's have you reaching for the volume knob anyway, as they provide such a clean presentation.

So, I think for the average hifi listener who likes vocal, 'midrangy' material, this combo is certainly worth an audition and you should not be put off by comments around the net about ATC's need 150W + of power.

That said, I have heard my speakers with a Pass Labs X250. Wow, very impressive, massive control of the bass line, percussion was the best I and the owner of the amp has probably heard (especially from a such a small speaker). The amp was so good though, you really would want to stay away from badly recorded material, it rendered it near un-listenable - so I guess nothing new here from that respect, as you read this everywhere.

Personally, I would put the little Nait ahead of even the ATC in terms of an enjoyable listen.

I need to try it more with a wider range of music, but so far I am pretty addicted.
 
Good to hear hear the Nait XS works with ATC speakers - perhaps Naim's current range is better suited for the task than the olive series: I had a NAC102/Naspc/HiCap/NAP180 combo that didn't gel with my SCM7's (first model). A Sonneteer Campion beat said combo hands down.
 
I have just upgraded to scm40 but had (still have!) scm11, I originally had a Creek classic 5320se rated at 105wpc, when I upgraded to sia2 150 the 11's were much happier but still didn't seem to get to very high volumes, before I bought the 40's I thought the loudness would take a tumble as there's now 3 speakers to drive, wrong! The 40's sound much louder. I use a naim cd5x which im happy with but haven't listened to any other source.
I suspect the 20's will give more volume per watt than the 11's
 
I used my 40s with an 82/250 setup for a while. They sounded fine, I swapped for the ATC amp as the 250 was getting pretty hot sometimes, and the integrated amp is a lot neater than a pile of Naim boxes. Certainly no night and day difference in SQ.
 
I listened to a 552/500 and SCM50 Anniversary and boy were they rough.

At one stage I was going through music on the ipad while music was playing in the background, loud and I just said without thinking "that's just noise" and to me it was, expensive but very harsh sounding.

I could think of better ways to spend €50k+
 
I have used the 6 pack 135 Naim active system with ATC SCM100s for 15 years.

I modified the ATCs by swapping the tweeters for Snanspeak revelators. Also rewired and re-socketed with Silverplate PTFE and Multicontact socket.

Amazing. The sound stage has massive depth but also height incredibly.

Technology moves on and i am now looking for a change.

I go for feeling and emotion in female vocalists. A monitor system like this does it.
 
Hi,
Do you mean six amps for active system, with no cross overs? How did you decide which scanspeak tweeter to buy? I built scm50 copies using standard drivers and crossovers designs found on the internet.
I am tempted when i have time, to buy a couple of raal ribbon tweeters which some of the top end speaker manufacturers favour.
 
Yes - 6 x 135s directly connected to the drivers – no crossovers (no power losses). The excellent Multi-Contact brand 32 amp gold plated sockets (Farnell) were fitted to the metal plates on the speakers. This was 15 years back – some manufacturers are now using these e.g. Leema on the Elements amp.

The matching shrouded plugs have been used with twisted PTFE /19 x 0.25 silver-plated copper equipment wire for bass and mid and 19 x 0.15 mm for top speaker cables.

I bought the ATCs with both the passive crossovers and the active amps built in. Unsurprisingly, the 135s/Snaxo 3-6/Supercap gave a massive improvement and I then sold the ATC amps.

I cannot quite remember on how I hit on the Scanspeak Rev. I perhaps read somewhere that the Vifa tweeters that ATC were using at the time could be bettered. Shaun Williams of Wilmslow Audio recommended them and they still available still much acclaimed. Shaun seems to have disappeared (??) He left Wilmslow years back.

I also have 2 pairs of kit Wilmslow Prestiges (also tried in active mode with the 135s). I built one pair and Wilmslow did the other. In the last 12 months I have modified both pairs of crossovers. One pair of crossovers have been re-built replacing some components with “esoteric” ones: Jantzen coils, Mundorf Supreme caps for Scanspeaks and Mills resistors in signal path. I tried the Caddock resistors but they killed the sound. Caddock are recommended on the remains of the Williams Hart web site. The other set have been just rebuilt with existing components (which includes the now unavailable Hovland Musicaps – sweet!). Both sets are now external in birch ply boxes (hard wired silverplated copper/ ptfe – no pcbs).

I have modified the crossovers circuit just a little having had the modified speakers professionally measured. The mid level (ATC 75mm dome) has been brought up significantly by simply changing a series 4.7 ohm for 1.2 ohm. The crossovers points could be improved to achieve the optimum 380 Hz and 3.8KHz. More of the audio is going to Volt bass and to Scanspeaks than desired.

I guess this needs to go in DIY as well.
 
Do you mean no electronics between the amp output and the speaker terminals? I have most of the bits for another Avondale Voyager, as i had been tempted to Bi amp the scm50s.
 
The six speaker cables are plugged into the 6 x 135s using brass/gold plated Multi contact plugs (not the Naim silver plated which probably contain a steel clip ?) and they go to the 6 sockets on the back of the each of ATCs or Wilmslows. The 6 wires inside each speakers then go directly to the drive units in each speaker. No gain without pain! This configuration has also enabled me to readily swap to external passive crossovers as desired.

It’s a standard active set up where external power amps are used. The separation of the frequency bands for each drive is done by the Snaxo 3-6. Over the years I adjusted the 6 pots in the Snaxo (one for the output to each 135) for best sound. I think that I saw Naim do this at an exhibition. (?)

CORRECTION:

The silver-plated PTFE insulated equipment wire that I have made the speaker cables from is:

19 x 0.45mm mid and bass (much higher current carried) and 19 x 0.25mm for the top.
 
That makes more sense, it sounded from your earlier post that you were running the 135s directly into the drive units with no crossover at all! Which I can't imagine would work for long...
 
Would i get the same benefit by disconnecting the connections between the three crossovers in each speaker and fitting the pots on each crossover.
 
Pots are used in passive crossovers but are best avoided for high end, in my opinion.

You just let the electronic snaxo crossover between pre and power amps. do its job.

Amps can do there job best with the direct connection particularly control in the bass.
 
Not sure exactly what you mean. Pots are used in passive crossovers between power amps and drivers but in my view are best avoided for high end. Pots can be used successfully in electronic crossovers like the snaxo because there is only a small amount of current going between the pre and power amps.

When I have experimented with bi, tri amping I have tried matching the output to each pair of power amps with Vishay resistors in series. These were located between pre and power amps. The the passive crossover section were of course kept in place at the speakers.
 
I have heard ATC SCM20 driven by Avondaled NAP135. It works very well all the way to very loud volume levels. However, having heard ATC driven by their own amps, I feel there is something special about it. There is a certain strain-less-ness about driving an ATC with a quality 100+ watts of pure class A amplification.
 
I agree, the ATC amp does seem to provide boundless power. I found the presentation too clinical though, sometimes good fun, but often not an easy listen. However, if you like the Naim sound, I think these speakers could be a good way to go. The Nait provides enough control for more than reasonable volumes though. They do not push the ATC's as much, but the voice and midrange are exceptional.

Personally however, I think I prefer my own Michell Alecto's having listened to this setup for over a week now. The Naim keeps the music very tidy around the midrange, but its not a big or realistic sound to me, it feels a little unnatural, perhaps its the PRAT I am hearing?
 
Hi halvis

Yes, I find that Naim amplification does work well ATC monitors. Some of our clients also use Olive and Black Naim amplifiers with ATC monitors.

All the best

Rick @ Musicraft
 
You must log in or register to reply here.


advertisement


Back
Top