Which Amp to buy? The most frequently asked question on this site. READ THIS!!

[TomDac]

"What would be a good amp choice for my MartinLogan speakers"?

That is the most common question we hear on the site. The folks at ML hear it too.

Selecting the right amplifier is a HIGHLY personal decision. Before asking the question again, here are some things you should read first:

MartinLogan's guidelines on finding a suitable amplifier:
https://www.martinlogan.com/en/support/faqs/q/190

A section here on the MLO site of recommended amplifiers: http://www.martinloganowners.com/forum/forumdisplay.php?64-Amplifiers
These are ML owners who have taken the time to write about the amplifier they're using with their system and what results they've had.

Search the "Members Systems" part of the site. Find owners with the same speakers you have and see what they're using.

Use the SEARCH function here at the MLO site. Read what others have asked and already answered!

An electrostatic speaker can dip down to less than 1 ohm in resistance, which many amplifiers cannot tolerate. An amplifier that doubles it's output when the resistance is cut in half (ie 250w @ 8 Ohms / 500w @ 4 Ohms, etc. ) is a good indicator that the amp is well built and stable.

As ML states on their site: ...it is important that the amplifier be stable operating into varying impedance loads: an ideally stable amplifier will typically be able to deliver nearly twice its rated 8 Ohm wattage into 4 Ohms and should again increase into 2 Ohms.


Do your research. Contact amplifier manufacturers and ask them questions about driving electrostatic speakers.

And lastly: You've made an investment in purchasing what we here at MLO consider to be the finest loudspeakers made. Don't cut corners when it comes to amplification.. Get the best amplifier you can afford. Your ears will be rewarded!
:music:

 

[MOON]

Simaudio amps mate with Martin logans very well and double the wattage into 4 ohms. The dealer I bought my first Siaudio amp from was also a Martin logan dealer saying they were a perfect match.

I am now running a Simaudio W8 amp. My friend is running W7 mono blocks. We have both run previously Simaudio W5 and W5 LE amps which are a bargain on the used market and can get you up an running. I have found it is best to mate Simaudio amps with Simaudio pre amps. There is synergy there in spades. Hope this helps.

 

[Carlsbad]

I got this advice before I bought an amplifier to drive my giant CLSs. I bought a Wired4sound STI1000 and it is rock solid. Couldn't be happier. Of course it is a class D amp. This is where a lot of traditionalist audiophiles get a divorce with ML. They are married to their 40 wpc Class A amps and just can't drive the big electrostats.

 

[JonFo]

An electrostatic speaker can dip down to less than 1 ohm in resistance, which many amplifiers cannot tolerate. An amplifier that doubles it's output when the resistance is cut in half (ie 250w @ 8 Ohms / 500w @ 4 Ohms, etc. ) is a good indicator that the amp is well built and stable.

I want to strongly reinforce the importance of this particular spec, as it is a great indicator as to whether an amp is suitable for ESL duties.
Not only will the impedance go very low, but it is also quite varied across the frequency spectrum (especially with older passive crossover ESLs); that is tough for an amp to be handling a wide frequency range into different impedances. To maintain a smooth frequency response, the ability to push the needed voltages in an even fashion is important.

Over 28 years of ESL ownership, I can attest to the quality of the Sunfire 'load invariant' amps, as I have a 27-year-old Sunfire stereo, a 22-year-old Sunfire Cinema Gand, and a 20-year-old CG Signature I bought new back in the day. All handle the ESL's just fine.

But the best amp I've found for ESL duties is the Sanders Sound Systems ESL amp, in either the base or the Magtech variant.

Every day, the Sanders ESL amp proves its mettle by driving the huge Monolith panels direct, with no crossovers (I run them in an Active XO setup), so it has to deal with the back-EMF, capacitance, and low impedance of the step-up transformer and panel. Does not break a sweat. Highly recommended for any ESL speaker.

 

[mentorron]

re TomDac's posting above, I commented on the forum he referred to:
(Quote A section here on the MLO site of recommended amplifiers: http://www.martinloganowners.com/forum/forumdisplay.php?64-Amplifiers
These are ML owners who have taken the time to write about the amplifier they're using with their system and what results they've had. (Unquote.)

I chose Tomaso's entry "Naim Poweramps 180 & 250) as he had Aerius speakers as I do (we may be a dying breed?). I have run them successfully for over 20 years with a "lesser" power amp (an Adcom 5 channel GFA600, using just 2 front channels) with no issues and no Aerius refurbs or upgrades yet. But then I'm almost 80 years old now, so what do I know ;-)

 

[audioxcel]

I have original Sequels. Over the years, I have used 5 different amps and never had an impedance issue with any of them. In order of use the amps were: Tandberg 3016A, ARC CL60 with KT88s, ML No. 23, ARC CL60 (again), ARC VT100 MKII, and now ARC D70 MKII. All have driven the speakers cleanly at any sensible listening levels and occasionally at "way too loud" levels.

I also use a Mirage BPS 400 subwoofer with an active crossover just under 80Hz from my CAT Signature MKIII preamp.

I would add that the difference in sound between the ACRC CL60 with KT88s was close with the CL60 having a more pleasant midrange (vocals) and the ML having a better controlled, more comfortable bass which was way more noticeable when I had 6550s in the CL60.

 

[BigGuy]

This thread appears to explain why even lower power Pass amps such as my XA-60.8s are a great match for M-L speakers...

https://www.diyaudio.com/forums/planars-and-exotics/1046-esls-amplifier-wattage.html

 

[user 49726]

Bought my system in 93'. I have the Quests with new stats and a Crown Macro Reference amp. The system still sounds amazing!

 

[Brasilofil]

I want to strongly reinforce the importance of this particular spec, as it is a great indicator as to whether an amp is suitable for ESL duties.
Not only will the impedance go very low, but it is also quite varied across the frequency spectrum (especially with older passive crossover ESLs); that is tough for an amp to be handling a wide frequency range into different impedances. To maintain a smooth frequency response, the ability to push the needed voltages in an even fashion is important.

Over 28 years of ESL ownership, I can attest to the quality of the Sunfire 'load invariant' amps, as I have a 27-year-old Sunfire stereo, a 22-year-old Sunfire Cinema Gand, and a 20-year-old CG Signature I bought new back in the day. All handle the ESL's just fine.

But the best amp I've found for ESL duties is the Sanders Sound Systems ESL amp, in either the base or the Magtech variant.

Every day, the Sanders ESL amp proves its mettle by driving the huge Monolith panels direct, with no crossovers (I run them in an Active XO setup), so it has to deal with the back-EMF, capacitance, and low impedance of the step-up transformer and panel. Does not break a sweat. Highly recommended for any ESL speaker.

I agree with you. I bought a Sanders Magtech amp for my newly repanneled CLSs and they sound fantastic.

 

[user 49726]

I have a pair of Quests that just got new stats last year. They sound great! But, my Crown Macro Reference amp is on it's way out. The entire system is circa 1993. But that amp gave me the power to push my Quests at any volume. I have an Ayon cd sx3 integrated cd player. Love that too! Would welcome recommendations on which amp to buy that will not only replace my Crown, but will improve the over experience, if thats even possible.

 

[Robert D]

I agree with you. I bought a Sanders Magtech amp for my newly repanneled CLSs and they sound fantastic.

Looks like those amp have a lifetime warranty for the original owner. Thats incredible! The price isnt insane either.

I wonder how these speakers sound?
Sanders Sound Systems - MODEL 10 Electrostatic Speaker

Seems there is a lifetime warranty on all of their electronics.

Sanders Sound Systems - Service and Support

Anyone here ever owned or at least heard those speakers?

 

[JonFo]

I wonder how these speakers sound?

I've heard them twice at demos during shows. Very impressed both times.
Part of their excellence is that he uses an active crossover with time-delay capabilities (the latter is critical) as part of the speaker system.
Being a flat panel ESL, they do have a narrow imaging range, but I believe that with appropriate rear-wave management (to mitigate the lateral 'pull' of reflected sound), they might work for a broader listening zone.
Roger's use of corner stradling deployment during demos in small showrooms is his method of mitigating that issue and works fairly well.

 

[Technomad]

Slightly left-field wrt most of the comments in this thread, but I've just had a revelatory experience with amps for my Spires. I'd started with bi-amping from my Arcam AVR20 receiver and the sound was excellent - great staging and transparency, but perhaps just a little harshness in the vocals and 'brassiness' in piano and some strings (although room tailoring is still under way). So I swapped in a mint Mark Levinson 331 (recapped) and everything took a step forward - clarity, transparency and staging all improved, with great refinement and delicacy. Which would have been fine, but I'd also recently bought, for our 'analogue' music room system, a pair of Michell Alecto II monoblocs, with the additional MOSFET upgrade by their original designer, Graham Fowler at Trichord Research. On a whim, I swapped these in to the main system, and was blown away - staging was bigger, deeper and more involving, bass control was superb and, above all, they had that elusive 'musicality' that has your toes tapping in all the right places. These amps are as rare as hen's teeth but, in 20 years of Martin Logan ownership, these are the best amps at anything approaching a reasonable price that I've come across for them.

 

[Lurch]

Currently driving my Summits with 90wpc Icon Audio MB845SEs using the 4 Ohm tap, and the sound is stunning. From a budget perspective I also had great success with a Quad 909, have also used Nord One UP SE NC500Ms (Hypex modules).

 

[donlduck1]

Driving my still wonderful Summits with Audio Research to my musical bliss.

 

[Bernard]

Driving my still wonderful Summits with Audio Research to my musical bliss.

Which ARC amp?

 

[twich54]

Slightly left-field wrt most of the comments in this thread, but I've just had a revelatory experience with amps for my Spires. I'd started with bi-amping from my Arcam AVR20 receiver and the sound was excellent - great staging and transparency, but perhaps just a little harshness in the vocals and 'brassiness' in piano and some strings (although room tailoring is still under way). So I swapped in a mint Mark Levinson 331 (recapped) and everything took a step forward - clarity, transparency and staging all improved, with great refinement and delicacy. Which would have been fine, but I'd also recently bought, for our 'analogue' music room system, a pair of Michell Alecto II monoblocs, with the additional MOSFET upgrade by their original designer, Graham Fowler at Trichord Research. On a whim, I swapped these in to the main system, and was blown away - staging was bigger, deeper and more involving, bass control was superb and, above all, they had that elusive 'musicality' that has your toes tapping in all the right places. These amps are as rare as hen's teeth but, in 20 years of Martin Logan ownership, these are the best amps at anything approaching a reasonable price that I've come across for them.

I'm guessing you meant 'Bi-wire' not Bi-amp

 

[Technomad]

I'm guessing you meant 'Bi-wire' not Bi-amp

No, bi-amp - the Arcam usefully has software-controlled bi-amping which allows you to assign unused amp channels to bi-amp the main speakers.

 

[twich54]

No, bi-amp - the Arcam usefully has software-controlled bi-amping which allows you to assign unused amp channels to bi-amp the main speakers.

interesting, considering that the bass driver is powered, why ?

 

[Technomad]

interesting, considering that the bass driver is powered, why ?

Experiment - I’d seen a number of posts to the effect that a) it actually does make a difference to the bass response and b) leaves a dedicated channel for driving the panels. My conclusion was that it did make a difference, mostly to to panel sound. However, the bigger improvement is from bi-wiring with either the Mark Levinson or the Alectos. I could take the experiment to its logical conclusion by bi-amping with the Levinson AND the Alectos, but can’t be bothered to dismantle the rack again!