Final Amplifier for Martin Logan CLX

[DonH50]

Having had numerous electrostatic speakers, I can only tell you that Solid State is not really the right choice. The impedance swings are too wide and often the speakers have too high impedance in the mids, which leads most SS to sound thin through that region on the speakers.

To avoid back EMF issues you need a good tube amp without negative feedback. If you look at something like VAC, I would go back in time a bit and try to find a pair of the PHI 70 monoblocks. These will deliver plenty of power to your CLXs and sound extremely good. Nevermind the 70 watt rating there is plenty of head room and they will deliver the voltage your speakers need through the higher impedance midrange. Other big push/pull triode or triode wired amps should be considered like the CAT JL2 signature (it should be stable). The Coincident 211 based push pull monos should also be on the audition list. You shouldn't discount big SET amps either from the likes of NAT (SE2 or Transmitter) or KR Audio (Kronzilla DX monos will work beautifully with the CLX), which would be my own personal preference over the push/pull designs.

Interesting, my experience is exactly opposite. I find tube amps struggle with the low impedance ESL's present at the top end, making them sound more edgy than airy, and do not control panel modes in the bass, making them sound more boomy/less tight than a good SS amp. And of course "good" means it must handle the low load.

An amp with little feedback and high output impedance by definition will not handle back-EMF as well as one with very low output impedance.

I love tube amps in the middle, and can live with their high end given they tend to roll off when presented with a low HF load, but unless it's a very large amp tube bass I find lacking. Overall my preference is for a great SS amp on a great ESL.

 

[MylesBAstor]

Interesting, my experience is exactly opposite. I find tube amps struggle with the low impedance ESL's present at the top end, making them sound more edgy than airy, and do not control panel modes in the bass, making them sound more boomy/less tight than a good SS amp. And of course "good" means it must handle the low load.

An amp with little feedback and high output impedance by definition will not handle back-EMF as well as one with very low output impedance.

I love tube amps in the middle, and can live with their high end given they tend to roll off when presented with a low HF load, but unless it's a very large amp tube bass I find lacking. Overall my preference is for a great SS amp on a great ESL.

That's not my experience Don with at least ML stats and modern tube amplifiers. Of course, the ML Summit-Xs are hybrids. And estats can drive SS amps just as crazy as tube amplifiers. . Ralph K. has talked about some of the reasons on WBF in the past here.

 

[DonH50]

I agree some SS amps do not like ESLs, in fact many of them probably really hate that HF drop in impedance up there where the amp's feedback is decreasing and output impedance is rising. Hybrids with active LF drivers take the LF issue out of the equation and would IMO tilt to the tube amp, but I would still try them out. Some tube amps just do not handle the HF load well (and yes nor do SS, conceded above). IME tube amps tend to roll off and their ringing is not (as) audible; SS amps tend to keep their bandwidth up and so if a SS amp has trouble with the high end, you hear it! Good point, Myles.

Last time I heard big tube amps on ESLs the amps were ARC (D-79, D-90), Jadis (couple of models, biggest and next one down), and CJ (Ref something, their beast) back in the late 90's/early 2000's. The ESLs at that time were friend's and from stores we worked at so included Acoustat, Beveridge, Quads, Soundlabs and a couple of MLs (hybrid and full-range). It was not just me; several owners with tube amps found they preferred SS though few wanted to give up their tube midrange (understandable). I have not heard them driven by the new breed of super-amps like the big ARC REFxx, newer Jadis, Atmasphere, etc. I would guess the 75 -150 W amps at that time just did not have low enough output impedance and wide enough power bandwidth; that may well have changed.

I am only stating my preference based upon my experience, dated it is, and questioning some of the technical info presented. I have no dog in this hunt but don't want to do SS a disservice. If I had pair of ESL's I would try both; I bet there are still trades, especially at price points below stratospheric (to me, probably to few others here).

 

[MylesBAstor]

I agree some SS amps do not like ESLs, in fact many of them probably really hate that HF drop in impedance up there where the amp's feedback is decreasing and output impedance is rising. Hybrids with active LF drivers take the LF issue out of the equation and would IMO tilt to the tube amp, but I would still try them out. Some tube amps just do not handle the HF load well (and yes nor do SS, conceded above). IME tube amps tend to roll off and their ringing is not (as) audible; SS amps tend to keep their bandwidth up and so if a SS amp has trouble with the high end, you hear it! Good point, Myles.

Last time I heard big tube amps on ESLs the amps were ARC (D-79, D-90), Jadis (couple of models, biggest and next one down), and CJ (Ref something, their beast) back in the late 90's/early 2000's. The ESLs at that time were friend's and from stores we worked at so included Acoustat, Beveridge, Quads, Soundlabs and a couple of MLs (hybrid and full-range). It was not just me; several owners with tube amps found they preferred SS though few wanted to give up their tube midrange (understandable). I have not heard them driven by the new breed of super-amps like the big ARC REFxx, newer Jadis, Atmasphere, etc. I would guess the 75 -150 W amps at that time just did not have low enough output impedance and wide enough power bandwidth; that may well have changed.

I am only stating my preference based upon my experience, dated it is, and questioning some of the technical info presented. I have no dog in this hunt but don't want to do SS a disservice. If I had pair of ESL's I would try both; I bet there are still trades, especially at price points below stratospheric (to me, probably to few others here).

Both bring different qualities to the table vis a vis say my review of the Cello vs. cj amplifiers on the Martin-Logans. But if an amplifier speaks the truth, it speaks the truth. I just also find that estats and the best speakers out there are just ruthlessly revealing--in a good way -- of all the upstream components. But when it's right, baby it's right! You don't need anyone to tell you!

FYI, remember that the smaller MLs shut down Russ's Spectral amplifiers.

 

[DonH50]

I had Spectral in mind, and a couple of other wideband amps that did not like the heavy HF load...

Not about to get into the "truth" debate, think I'd best wash my hands of that one.

I've always had a soft spot for ESL's but kept coming back to my Maggies for overall sound. It's like debating which 9/10 is better.

p.s. No shock to you or anyone who knows me, but I disagree with this quote: "Skepticism is the sadism of embittered souls." Out of curiosity, who said it?

 

[RogerD]

I had Spectral in mind, and a couple of other wideband amps that did not like the heavy HF load...

Not about to get into the "truth" debate, think I'd best wash my hands of that one.

I've always had a soft spot for ESL's but kept coming back to my Maggies for overall sound. It's like debating which 9/10 is better.

p.s. No shock to you or anyone who knows me, but I disagree with this quote: "Skepticism is the sadism of embittered souls." Out of curiosity, who said it?

Emile M. Cioran

 

[DonH50]

Thanks. Interesting person, I had never heard of him. I expected it to be a slam of skepticism, which it may well be given his history, but seems like someone I should know more about.

As a devout realist/pessimist I have often quoted Mao Tse-tung: "It is darkest before it goes totally black." Probably one of the few things we could agree on; politically and religiously I think we are opposites.

 

[MylesBAstor]

Thanks. Interesting person, I had never heard of him. I expected it to be a slam of skepticism, which it may well be given his history, but seems like someone I should know more about.

As a devout realist/pessimist I have often quoted Mao Tse-tung: "It is darkest before it goes totally black." Probably one of the few things we could agree on; politically and religiously I think we are opposites.

Perhaps you like "trust no one?" Fox Mulder

 

[DonH50]

...including myself...

Actually I'm not quite that bad... Trust but verify?

 

[awsmone]

Just an update

So far The Bakoon amps are breaking in nicely

Bass is INCREDIBLE lowest double bass notes produced clearly

Bass drum and timpani natural with slam when required

Thump in the chest from a PANEL ?!

Midrange top end

No harshness

Great sound stage

Amazing depth I mean deep and wide

The stage seems to be populated with players in very specific spots

Still opening up….but very pleased so far !!!!!

 

[Garth]

Just an update

So far The Bakoon amps are breaking in nicely

Bass is INCREDIBLE lowest double bass notes produced clearly

Bass drum and timpani natural with slam when required

Thump in the chest from a PANEL ?!

Midrange top end

No harshness

Great sound stage

Amazing depth I mean deep and wide

The stage seems to be populated with players in very specific spots

Still opening up….but very pleased so far !!!!!

Good for you glad you found a amp that works for you