Recommended Tube Amp for ML CLS I model


Happy holidays!

I've just acquired a pair of CLS I speakers with recent panel upgrade. I know this speaker is supposed to be tube friendly (higher impedance) and the easiest to drive of the CLS range. I am very familiar with the IIz model, but that has very different characteristics from what I understand.

I'm looking to pair a good tube amp with these speakers, to be driven by a Tact 2.2 Mini digital preamp that will be configured to send lower frequency signal to a REL sub and a time-aligned mid / upper signal to the CLS via a Tube amp. (I used a similar setup with an Accuphase DF-35 Digital dividing network and CLS IIz and REL - the Tact is a cheaper option if you just need to 2-way xover division). The digital discussion can take place in another thread.

For now, I am looking for a good tube amp to drive the CLS I model. Since the digitally split signal will be sans deep bass, low frequency performance is not a high priority. So far, I'm looking at ARC VT130SE and VT150 monos (both nice, but a lot of negative feedback used), Rogue Zeus (triode mode), ARC VT100, ARC VS115, Atma-Sphere OTL (with autoformer?), etc.

Any recommendations from those familiar with the original CLS?

TIA!
fdriver
12-27-10: Fdriver
Dover - are you referring to the Original CLS, II, IIa, or IIz?
Original CLS, but have also experience with CLS II. My caution would be that some valve amps work, some dont. For example VTL Compact 100's ( 100w ) couldn't drive them, yet a 20w Leak Stereo 20 could. My recommendation would be to audition before you buy if possible. FWIW I preferred the original CLS with upgraded panels ( original single transformer crossover ). The Quicksilvers produced the most transparent and wonderful soundstage despite Mike Sanders rolling his eyes when I told him what we were using with the Q's.
Well, I believe ones results with the CLS speakers will vary upon the type of listening one does. What drives ML's best in general has been beaten to death on previous threads about it. Do a search and you'll get the phone book of opinions.

Having owned the CLSiiz's, on my second pair now, my listening levels aren't demanding. I listen to acoustic jazz, and believe it or not I drove my iiz's to more than adequate levels for my modestly sized room with a 10 watt Class A SET 300B tube amp. The belief is these speakers require high current amps before they'll deliver the goods. That's not been my experience. I've used Plinius and Pass amps of modest power ranges with more than pleasing results.

I agree that it's foolish to expect a planar speaker of the CLS' magnitude to deliver high quality bass. That's not what the speaker was designed to do. Acoustic bass of natural tone and volume is the best one should expect from these speakers. But of course, being the jazz listener that I am that suits me just fine. Earshattering level listener's have far more demanding requirements of the speaker than do I. But I don't believe one has to spend countless or unnecessary thousands on attempting to acquire mega power amplification to gain a reasonable level of satisfying output from CLS's. Having owned a countless number of ML hybrid's the CLS's are the best of the lot as far as my ears are concerned and certainly worth whatever effort necessary to get them dialed in to your liking.

I highly second the poster who suggested tilting the speakers forward at a slight downward angle. I've got mine on a pair of Arcici stands at a slight downward angle which lines up perfectly with my ears at listening chair level. It doesn't get any better than this. Mine are mated to an SVS sub. Enjoy your new purchase!

Was that the walnut pair of CLS's recently observed on ad with brand new panels? Perhaps not, for I could swear those were advertised as CLSiiz's.
HI Dover,
I have an ARC D250 on my CLS IIA's not because I listen at ear shatering levels but because it is a great amp. These speakers need a great amp. Up stream, I have an ARC SP-11 Mk II preamp. I have no idea what the lower power limit of these speakers is and, frankly, low power per se does not interest me. In general I do prefer a lot of power for any speaker as long as it is high quality power. The lowest power I have had on these speakers was the ARC D115 at 100W/chan. It definitely did not sound as good as the D250. Was it the power difference or something else. I think it was both. Besides power, the D250 is just a better amp.

I listen to very broad variety of music, mostly on vinyl. However, I do have a number of carefully chosen CD's that can push the system to amazing levels especially in the bass. This is where the CLS's fail both from a frequency response and dynamic range point of view. Good (underline GOOD) subwoofers take these speakers to world class levels.

Sparky
The CLS 1 is a very different animal from succeeding CLS models. It is a lot higher impedance and is easily driven by tubes. This is not the case with the later versions.

Our MA-1 is a 'match made in heaven' on the CLS 1 according to our customers. We don't have much experience with our smaller amplifier models on the speaker as it was discontinued early on.

However several of our customers have commented to us that M-L still has all the parts for the speaker, and one of our customers actually bought a set of them and built his own 'CLS 1s'. It seemed that they ran fine with his M-60s, but as that is the only case I know of; I feel like we don't have enough statistics to say more.

It would be my *guess* that the S-30 would need a set of ZEROs to accommodate the high frequencies, but one would have to try it to see.
HI Atmasphere,
I can't believe I spent all my words and you didn't understand that my ARC D250 is a tube amp. I can assure you that my CLS IIA's works great with these tubes.

I would have to check but I don't think the original and succeeding models are all that different impedance wise. I do know they sound different. I didn't like the originals and bought Apogee Calipers instead.

I must admit that my negative impressions might well have been caused by the system it was demoed in. At that time I did not understand the CLS's sensitivity to the system context.

Sparky