Gamut M250i mono blocks vs ???

[Hear Here]

Roy Gregory recently wrote a blog post about the subject of the "grip of the magazines" and how times are changing. You can check out his recent blog/review site gy8.eu for other interesting articles as well. There are even some of the on-line reviewers calling out some of these highly lauded reviewers for their lack of anything that resembles a real listening space.

I am attaching the link to the article here. I hope it doesn't break any rules.

Is There A Glass Ceiling Operating In Audio? - Gy8

Maybe not any more…

gy8.eu

We seem to have gone off at a tangent - discussing reviews / reviewers rather than GamuT amps!

However, there are far too many people who have little real reviewing skills or equipment and just record themselves prattling along about a piece of kit they have in their own room. Frankly I don't waste time looking at these self-appointed Youtube reviewers. A reputable magazine will employ or commission respected and knowledgeable reviewers to review equipment for inclusion is their magazine. If they didn't go down this fair and unbiased route, they'd soon lose their readers and income. Personally I regard Stereophile as the best source of reviews, but it's a fact that they review only stuff that is handled by a certain number of dealers - ie not the stuff you find peddled on Ebay or the stuff that Joe Bloggs knocks up in his garage and sells direct. Although Stereophile's reviews have shrunk from about 15 pages to 2 or 3, I have no issue with that provided there is honest, unbiased and accurate information provided.

 

[JayDee]

Musik Lab is not a very good website. It lists amps and one preamp, but no information about them. No pictures and no prices. I think they basically want to sell electric violins.

Yes. Same person. He does not push his amps and makes them for the people that know. I am sure he could sort that issue though

 

[JayDee]

Roy Gregory recently wrote a blog post about the subject of the "grip of the magazines" and how times are changing. You can check out his recent blog/review site gy8.eu for other interesting articles as well. There are even some of the on-line reviewers calling out some of these highly lauded reviewers for their lack of anything that resembles a real listening space.

I am attaching the link to the article here. I hope it doesn't break any rules.

Is There A Glass Ceiling Operating In Audio? - Gy8

Maybe not any more…

gy8.eu

Will have a read. I think the Industry is changing. The best ‘sound per pound’ is not mainstream stuff. Perhaps it is not a co-incidence that i followed my ears and ended up with Totaldac (for 6 years now) and z-axis Symetrica. Both small artisan specialists when i bought them. Totaldac are growing but still only sell direct in Europe. I am also a real supporter of Max Townshend stuff. His passive pre worked wonders and i love his F1 cables. So by default i have ended up with artisans rather then brands.
When i had the Gamuts up against CH Precision, Soulutiin, Tad, and others it took Berning Quadratures and the Totaldac Amp to make me sit up. After a few years with the Quads i love the ease of the top end but miss the grip and bass control, hence re discovering the sheer brilliance of the Gamuts. With the upgrades Michael has done i expect things to get better.

 

[musiklab]

Hi , thanks to all for the kudos about the Musiklab and GamuT amps , my name is Michael Edinger, I live and work in cph area , Denmark.
Always working as a self owned independent 1-horse company, working for GamuT among others, ( and the previous SiriuS ) I designed the GamuT M250 unit , the C2 and D3 pre amps, the Di150 , the S300 internal chassis, and built all 9 of them, and developed many iterations of the audio electronics, such as the award winning D200 and M250 mk0 mk2 , Mk3 , and the very same boards were used in the latest years "i" models up to the final closure of GamuT electronics. I keep complete records of all my work, blueprints etc . After the Di150 , I stopped working for GamuT in 2005. I repair and upgrade GamuT amps going 25 years back, since no one else seems to bother help original owners keep their cherished amps. Now I make new models D220 and M250 to order, plus my new D1 line preamp , at more reasonable prices than GamuT´s final list prices.
I used to play and I also make my own violin, cello and bass amplification system named "StringAmp" (.com) tm. - , but only wish to have one website , so I combine the two . If you need to find me , it is possible.

 

[Ground Control]

Hi Michael, Can you describe the relationship between the Reiymo KAP-777 and Gamut amps and how/why the 777 came to be?

 

[Hear Here]

Hello Michael. Good to hear from you. I bought the GamuT D200 Mk III a few years ago and it was probably the best sounding of the 12 amps I bought or borrowed to find something ideal for my Avantgarde speakers. This was after having used SETs for 15 years and taken the decision to move to SS if I could find something equally satisfying.

However the GamuT had one feature that condemned this amp - and it's a feature that is admitted in the User Guide, even in the latest i version. With sensitive speakers the start-up and power-down thump was quite unacceptable if one cares for the well-being of 100+ dB speakers!

The really annoying thing is that most amps have a soft-start whereby the amp is not connected with the speakers until the amp has settled down and thumps are easily avoided. Reluctantly I sold the GamuT for this single feature.

As you seem to have been involved in its development through the various iterations (Mk I, Mk II, Mk III and i) could you shed any light on why this obviously undesirable feature was allowed to continue un-fixed for decades? I'm not blaming you but GamuT, but it would be great to learn why things weren't corrected much earlier. Thanks. Peter

 

[musiklab]

Peter, components deteriorate as they age, and the thump problem you mention might be related to that. Your Mk3 might be from ca. 2000-2003, about 20 years. The D200 protect circuits constantly monitor DC, over current, overheating, sub- and supersonic issues from outside the audio path and should make sure that no electrical problems make it to the speakers. My later circuit boards have modified the protect ( and many other things ) , and after turning it on, a new amplifier should have settled so much only a minute click is heard from the speaker when the speakers are connected, about as loud as the relay that does this. But these amps often last for decades, and then age issues show up. Owners send their aging and defective D200´s to me for upgrading , where the complete audio boards are changed for versions with a number of modifications to counter the aging process, enhance robustness and performance, In essence it´s a new amplifier. GamuT being constantly financially challenged never bothered to keep developing the circuits, so even the very last GamuT "i" amps assembled by Kvist use newly made circuits, designed by me around 2000-2001, despite all exotic claims.

 

[musiklab]

Hi Michael, Can you describe the relationship between the Reiymo KAP-777 and Gamut amps and how/why the 777 came to be?

Kap -777 is in part based on Musiklab power amp circuits. It is a fine amp , very well made with japanese attention to minute detail. Looking hard , you may find my name very discreetly mentioned among the many fathers of this.

 

[Knopf405]

First time poster, but felt compelled to share my experience with Musiklab and more importantly its creator Michael Edinger. I grabbed I would assume one of the few used Musiklab d220's in the US a couple of years ago. I knew little about it other than it was related to the Gamut and I had recently grown fond of SS amps with either one or two output devices from the likes of Pass, Valvet and a few others, but those commonly have 100w or significantly less. I have had the good fortune to own many of the most highly touted class A and A/B, hybrid, etc amps from Europe, as well the typical US heavyweights over a 25 year period. To me the D220 struck a new balance of purity of tone, top to bottom coherence, timing and most impressively for its real world power rating, the intimacy of the single and dual output designs I had become familiar with. There are no multiple parallel device amplifiers that can compete in that last regard in my experience. The D220 was and is still easily the most complete (avoiding the word "best") SS amp regardless of cost I have ever owned, and it is not remotely the most costly. Like all things audio there is always my personal preferences woven into any such statement. That being said it is perfectly at home and does complete justice to the most vaunted of upstream components and unlike most mosfet amps, actually doubles down as impedance dips.

Every bit as fascinating is Michael's story. These designs are all his, the Gamut lineup. It is not easy to tame the two high powered Mosfets in these designs, they are not easily driven either, the drivers on them are small power amps themselves. Michael is one of the most humble men in audio you will come across. No where in any of Nelson Pass' recent 15 year side venture into single and dual output device amplifiers will you find credit given to Michael's original design in the Sirius amplifiers. Michael dabbles in all sorts of work from the restoration of vintage recording equipment to making what many professional musicians consider some of the finest pick-ups in the world. He will make you an amplifier if you ask him nicely and also rescue Gamut owners with a tune up. They are all his designs and all from very early on and were never successfully improved upon by Gamut after he left. Michael on the other hand, never stopped working the circuit......

There really is no other SS amp design anything like it and it all stems from the chosen output devices intended for arc welding and capable of extremely high linear output that fortunately also happen to sound really good. In audio applications those two devices would be limited almost exclusively by the size of the power supply you could tolerate feeding them hence the birth of the over the top s300. I would venture a confident guess that the (9) units in existence of S300 Gamut amplifiers that I certainly will never hear or see that Michael made in his garage for Gamut many moons ago could quite possibly be the finest most complete top to bottom high powered SS amps that have ever been made. Very few people know of their existence let alone would place them in that conversation. Every other amp that would be in that conversation, able to drive any speaker in existence, would all have one thing in common that Michael's design would importantly lack: a sea of redundant repeating output devices as the power rating increased and along with those rows of parallel devices, layers of additional complexity and compensation to keep them in line and in synch. Not so in Michael's design, same two little output devices that are in my D220, but in the s300, a literal ocean of reserve sitting behind them to tap into......If you look closely at the S300 you'll spot them . There is no other amp I am aware of that scales in such a simple fashion. The s300 weighs 440 lbs, 439 of it is power supply.

Michael is a gentleman and no doubt a genius who has spent a big part of his life getting the most out of these same two output devices. I would encourage any of you whose systems are well known to you and rarely in flux, that while he is still around and willing and more importantly, wanting to make amplifiers, that you do yourselves a favor and ask him nicely to make you one You won't let it go.


S300 Pic

 

[Ron Resnick]

Welcome to WBF, Knopf405!

 

[JayDee]

Really interesting post above.

I can confirm Michael has sprinkled some magic on my amps. Having sent him my Gamut Mono block M250i’s michael found identical defects in both boards, leading us to assume a manufacturing issue rather than degradation. His final note to me suggests i now have the finest sounding Gamut M250i’s in existence as he did some extensive tweaks, including reducing the warm up time.
I still get the thump, with one amp a little worse than the other, but I love the sound. The control and the ease of presentation along with a super-natural top end is simply glorious.

i cannot ever see myself selling these amps.

 

[musiklab]

@Hear Here: So many mentions of a debilitating startup Thump. Ravaging delicate 100db+ sensitive speakers without mercy -- But the amp in question was sounding fine so probably not defective - Or , I wonder, is it real ?
What: The musikLab/ GamuT power amp has a comprehensive protect + delay circuit, with a relay connecting it to the speaker terminals only when operational safety conditions are met. Mind, this is an amplifier circuit commanding dynamic power up to 1kW ! - that also will produce sound comparable to dainty valve amps when so required.
How: A steady influx of aging GamuT and MusikLab units come in for upgrading or repair at my workshop. I checked startup and shutdown clicks/thumps among a random selection of them while listening, checking with a Lab scope to catch the waveform and magnitude of these "earthquake" events.
Result: I found the worst "offenders" were emitting a pulse amplitude of max. 10milli - Volts peak (Yes , that is a total of 12.5 micro-Watts power into 8 Ohms), once after a short turn-on delay, and once after a shutdown delay. Other units made peaks around 3 mV. While these -thumps- may well upset a hyper-delicate ear listening for tiny problems, they simply can not damage any speaker, or headphone able to reproduce music at barely audible volume. If this is still perceived as unbearable, I think a longer on/off delay for settling could be a remedy, if the amp´s sound is appreciated.
IRL, I find it a non-problem, blown out of proportions.
Best Regards Michael

 

[Hear Here]

While these -thumps- may well upset a hyper-delicate ear listening for tiny problems, they simply can not damage any speaker, or headphone able to reproduce music at barely audible volume. If this is still perceived as unbearable, I think a longer on/off delay for settling could be a remedy, if the amp´s sound is appreciated.
IRL, I find it a non-problem, blown out of proportions.

Sorry, but with ultra-sensitive speakers, the start-up and shut-down thumps do threaten the wellbeing of these speakers. I would not have resold my GamuT D200 Mk III had these thumps been as you describe - barely audible.

Of course, this beefy amplifier is not really designed for high sensitivity speakers, so the vast majority of users will hear a modest sound through their speakers - but not if the speakers are 107dB.

The original design should have included a simple relay that effectively disconnects the amp from the speaker until the amp has settled down after turn on and likewise the instant it is switched off. Most modern amps cater for this and include relays.

As I say, no problem in most systems, but a serious enough one that horn owners should probably look elsewhere for their amp unless a relay is retrospectively fitted to a GamuT amp. Despite this, the GamuT sounded wonderful and its control and clarity of bass in particular was probably the best of the 12 amps I home demo'd before settling on one to keep. Peter

 

[musiklab]

I am grateful for your kind praise of the amps sonic ´s , also noticed with your super sensitive speaker system - this goes to show that its first watt is as clear as its max at 200W /8R
But as I said in #52 : these amplifiers DO include relays , clearly announcing themselves after power on, as 2 separate, delayed tiny mechanical clicks when connecting to the loudspeaker terminals, after a protect circuit monitoring the system (from outside the audio circuits) has determined all systems working OK - and after switching off, they disconnect in a similar way. The protect thresholds ensure that even the most delicate of speakers will suffer no damage.
Any dainty 8W SE 300B valve amplifier making music will produce a speaker voltage way beyond this tiny impulse. However, IF the unit in your case was bought second hand, and causing such concern, this specific amplifier should have been checked for aging symptoms, before denouncing every unit of the same origin as most likely harmful. But I agree that with this 200W rms cl. AB SS amplifier, a 107 or 104 dB spl /w speaker system is really not needed. It will happily drive most loudspeakers to user satisfaction, and none to destruction.

 

[Hear Here]

But as I said in #52 : these amplifiers DO include relays , clearly announcing themselves after power on, as 2 separate, delayed tiny mechanical clicks when connecting to the loudspeaker terminals, after a protect circuit monitoring the system

Unfortunately when I sold my D200 Mk III, I sent the User Guide to the new owner. However this manual clearly stated that there would be a sound from the speakers on power up and down, but that it wouldn't harm the speakers. Your description of a click within the amplifier itself, indicating a relay, is not what the manual was describing and not what happens in reality. Perhaps you could dig out the manual for this amp (or Mk I or II) to check out the precise wording. As I mentioned before, it was only because this thump was so serious with my 102 dB sensitivity horn speakers that I sold the GamuT. Otherwise it was a great sounding amp. Peter

 

[Juha66]

I have own GamuT d200mk3 and D3 pre over 15 years now. Great sounding duo, best l've had. During that time i haven't had any issues with them. When i power them up, there will Be 2 small clicks from preamp and thump from the speakers, when amp is powered on. Manual says " you can hear 2 small clicks inside the amp, when powered on ". I have never heard those clicks inside the power amp, but that thump from speakers i hear.

 

[Hear Here]

When i power them up, there will Be 2 small clicks from preamp and thump from the speakers, when amp is powered on

That's my experience with the D200 Mk III, but the speaker thumps were on start up and power down. The User Guide did warn about these thunps, but described them as slight! Because of the high sensitivity of my speakers (107 dB) the amp had to go. Pity as the sound was wonderful as you say.

Why coudn't GamuT have included a delay relay so that these surges could be prevented from reaching the speakers - as many other amps so?

 

[Gregm]

Sorry, but with ultra-sensitive speakers, the start-up and shut-down thumps do threaten the wellbeing of these speakers. I would not have resold my GamuT D200 Mk III had these thumps been as you describe - barely audible.

Of course, this beefy amplifier is not really designed for high sensitivity speakers, so the vast majority of users will hear a modest sound through their speakers - but not if the speakers are 107dB.

If the signal's power is in the region of milliwatts, you wouldn't need to worry at all about damaging the speakers. The drive units are surely designed to operate to at least 20W continuous (many Lowthers are rated at 100W, an AER I once had was +35W). No doubt, of course, the actual thump -- i.e. the tone and the volume -- is very scary and if nothing else, annoyingly distracting.

I remember literally falling off my chair when listening to a pair of 101dB, Lowther-based speakers, driven by a 2A3 based tube amp -- i.e. flea power if that. Having switched to variable output on the DAC, I inadvertantly forgot to turn the volume down (i.e. I was at 0dB FS). The sudden result, as I remember it, was Akiko Meyers blasting Vivaldi full-scale... and I was certain I had just damaged two expensive Lowthers.
Which I hadn't of course, the amp max output was a tad over 2W... but the volume was scary loud (probably in the area of 105-6dB)!

 

[Juha66]

That's my experience with the D200 Mk III, but the speaker thumps were on start up and power down. The User Guide did warn about these thunps, but described them as slight! Because of the high sensitivity of my speakers (107 dB) the amp had to go. Pity as the sound was wonderful as you say.

Why coudn't GamuT have included a delay relay so that these surges could be prevented from reaching the speakers - as many other amps so?

Well, you didn't have to crank up the volume too mouch with speakers like that. Yes, there is the thump also when powered down.

 

[Hear Here]

Well, you didn't have to crank up the volume too mouch with speakers like that. Yes, there is the thump also when powered down.

The volume of the thunm is irrespective of the volume setting. It is a discharge of energy that developes during the warm up procedure - or something like that! Even at nil volume the energy discharge is there both on power up and power down - and it could easily be avoided by a delay relay to disconnect the speakers until the amp is booted up and rearing to go!