Hi eclnj,
Excellent. Thanks for posting.
Well, at last we can see that Les was talking out of his ***, even on his top design.
Pity really. His idea of a "hyperbolic function non-switching driver block" would be the holy grail for me.
I can't believe he so blatently had a zobel network & and an electrolytic input cap! shame.
How did your amp die ?
cheers
Andy
Excellent. Thanks for posting.
Well, at last we can see that Les was talking out of his ***, even on his top design.
Pity really. His idea of a "hyperbolic function non-switching driver block" would be the holy grail for me.
I can't believe he so blatently had a zobel network & and an electrolytic input cap! shame.
How did your amp die ?
cheers
Andy
Sage Supermos - More Info
I have been looking for search hits for Sage Supermos amplifiers on and off for many years now and thought you might like to hear about my experience with these amplifier modules.
In the early nineties I was looking for an exceptional CD replay system. I bought a Meridian transport, built an Audio Synthesis Dax DAC/ passive control unit and made a clone of the PMC LB1 transmission line speakers using Dynaudio units. I was still looking for the ultimate amplifier when I read the Sage adverts and literature. I wrote to Les Sage asking some non-technical questions, receiving a rather eccentric two page reply. I was still not convinced on the basis that if it looks too good to be true…….. it probably is. However, I had a good rapport with David Heaton at Audio Synthesis at the time and asked him about the Sage modules. He said that they had heard the modules and were impressed by them. He told me that they were trying to persuade Les Sage to work in partnership with them to build some modules in pucker cases with ultra high spec power supplies for listening and reliability(!?) trials, but he rarely answered the phone, fax or post. Eventually David contacted me and asked if I would like a pair of Sage mono blocks constructed by AS. I said that I would and in January 1992 I received my mono blocks delivered by David. They were built around the Sage Supermos 500 unit and used an Avel-Lindberg electromagnetically shielded 530VA, 52-0-52 toroids, high current bridge rectifier, a Sage 0V dc protection module, and 4 x Elna Cerafine 80V 10,000uF reservoir caps. Despite what I have since read about the circuit design and components used, THEY SOUNDED STUNNING. They had a wonderfully natural and fluid mid-range, taut and musical bass and a top end that was detailed, but never sounded harsh or hard. I was in audiophile heaven. But after about 2 years, one of my Sage units suffered much the same fate as most peoples seem to have with one of them blowing with a rather loud pop after being turned down following a ‘heavy session’. I contacted David Heaton again to find out that Les Sage had died. In truth I was told that he had not died in a car crash, but had committed suicide. I do not know the truth in this matter, but this is what I was told. AS were still impressed with the units but realised that there was an inherent design fault and had tried to buy the designs from his wife…. to no avail. AS then went on to design and build their Desire power amplifiers. I eventually sold my one broken and one working amps for more than one would have believed, as at this time there were desperate people about with broken Sage units. I did try and find out more about the design and was sent a schematic of the Sage Supermos 2 with some guidance as to what the design problem maybe, but I didn’t pursue this further. I still hanker after that sound, despite what I read about the design and construction, preferring to believe my ears and experience rather than pure science.
I have the following documents and if they would be of interest I would be happy to post, or e-mail them:
It was good to read the two Sage threads in this forum and look forward to reading more. I am not technically minded and would be very interested if someone could get to the bottom of the design and build a reliable unit with quality components. I know……….….. dream on.
I have been looking for search hits for Sage Supermos amplifiers on and off for many years now and thought you might like to hear about my experience with these amplifier modules.
In the early nineties I was looking for an exceptional CD replay system. I bought a Meridian transport, built an Audio Synthesis Dax DAC/ passive control unit and made a clone of the PMC LB1 transmission line speakers using Dynaudio units. I was still looking for the ultimate amplifier when I read the Sage adverts and literature. I wrote to Les Sage asking some non-technical questions, receiving a rather eccentric two page reply. I was still not convinced on the basis that if it looks too good to be true…….. it probably is. However, I had a good rapport with David Heaton at Audio Synthesis at the time and asked him about the Sage modules. He said that they had heard the modules and were impressed by them. He told me that they were trying to persuade Les Sage to work in partnership with them to build some modules in pucker cases with ultra high spec power supplies for listening and reliability(!?) trials, but he rarely answered the phone, fax or post. Eventually David contacted me and asked if I would like a pair of Sage mono blocks constructed by AS. I said that I would and in January 1992 I received my mono blocks delivered by David. They were built around the Sage Supermos 500 unit and used an Avel-Lindberg electromagnetically shielded 530VA, 52-0-52 toroids, high current bridge rectifier, a Sage 0V dc protection module, and 4 x Elna Cerafine 80V 10,000uF reservoir caps. Despite what I have since read about the circuit design and components used, THEY SOUNDED STUNNING. They had a wonderfully natural and fluid mid-range, taut and musical bass and a top end that was detailed, but never sounded harsh or hard. I was in audiophile heaven. But after about 2 years, one of my Sage units suffered much the same fate as most peoples seem to have with one of them blowing with a rather loud pop after being turned down following a ‘heavy session’. I contacted David Heaton again to find out that Les Sage had died. In truth I was told that he had not died in a car crash, but had committed suicide. I do not know the truth in this matter, but this is what I was told. AS were still impressed with the units but realised that there was an inherent design fault and had tried to buy the designs from his wife…. to no avail. AS then went on to design and build their Desire power amplifiers. I eventually sold my one broken and one working amps for more than one would have believed, as at this time there were desperate people about with broken Sage units. I did try and find out more about the design and was sent a schematic of the Sage Supermos 2 with some guidance as to what the design problem maybe, but I didn’t pursue this further. I still hanker after that sound, despite what I read about the design and construction, preferring to believe my ears and experience rather than pure science.
I have the following documents and if they would be of interest I would be happy to post, or e-mail them:
- Sage Audio eight page mini ‘brochure’
- Sage Audio four page price list dated Feb-July 1991
- Sage Audio two page ‘Supermos Kits’ leaflet
- Sage Audio, two page ‘Supermos 2’ design change leaflet
- Sage Audio, two page letter in reply to my non-technical questions, signed by Les Sage
- Audio Synthesis letter with specs of my amps and proposed input filter (not incorporated into my amps)
- A Schematic for the Supermos 2 amps from a friendly chap who has ‘de-potted’ the module
- A short letter from the same guy which includes a brief description of the design and possible causes for premature failure
It was good to read the two Sage threads in this forum and look forward to reading more. I am not technically minded and would be very interested if someone could get to the bottom of the design and build a reliable unit with quality components. I know……….….. dream on.
Hello ianwiebkin
Thanks for the info. I too loved the sound of my amps. I think that the very compact layout possible with encapsulation allowed him to get the best out of a traditional class AB design.
My anger was more from an engineering standpoint as I am a designer and wanted to see that someone had managed to make a neat non-switching configuration. (Hill Audio managed non-switching but needed coupling transformers to drive each transistor bank, they too sound great)
I am interested in 3 of the documents you listed:-
1) Sage Audio, two page letter.....
2) A Schematic for the Supermos 2 amps......
3) A short letter..........a brief description of the design....
If you could post them that would be great. I posted a .jpg image with a resolution lowered as much as I could without them becoming unreadable. (Not sure was file size limits are on this site)
regards Andy
Thanks for the info. I too loved the sound of my amps. I think that the very compact layout possible with encapsulation allowed him to get the best out of a traditional class AB design.
My anger was more from an engineering standpoint as I am a designer and wanted to see that someone had managed to make a neat non-switching configuration. (Hill Audio managed non-switching but needed coupling transformers to drive each transistor bank, they too sound great)
I am interested in 3 of the documents you listed:-
1) Sage Audio, two page letter.....
2) A Schematic for the Supermos 2 amps......
3) A short letter..........a brief description of the design....
If you could post them that would be great. I posted a .jpg image with a resolution lowered as much as I could without them becoming unreadable. (Not sure was file size limits are on this site)
regards Andy
Hi ianwiebkin
Thanks for the scans.
No surprise to me that the circuit is pretty much the same as the 'bog standard dsign' supermos500 posted earlier.
The comments letter from your friend reflected that.
The letter from Les had no technically useful comments but I have to agree TOTALLY with his comments on the hi-fi press.
They are totally at the mercy of their advertiser, and it shows.
Thanks for completing the design trilogy.
All that is missing now is the early bipolar 100w jobbie that sold alongside my Supermos - the Superamp.
Don't expect any surprises there!
regards Andy.
Thanks for the scans.
No surprise to me that the circuit is pretty much the same as the 'bog standard dsign' supermos500 posted earlier.
The comments letter from your friend reflected that.
The letter from Les had no technically useful comments but I have to agree TOTALLY with his comments on the hi-fi press.
They are totally at the mercy of their advertiser, and it shows.
Thanks for completing the design trilogy.
All that is missing now is the early bipolar 100w jobbie that sold alongside my Supermos - the Superamp.
Don't expect any surprises there!
regards Andy.
The Missing Monoblock modules...
Hi All ....
Well, after just siting down at the p.c (not being able to get any kip) I decided to do a search on Les Sage and see if anyone had continued an interest in his work.
Well, I was amazed to see the number of hits that Google brought up, and especially the threads on this Forum!
I was really interested in knowing what chemical to use to be able to de-pot the Sage modules
, and was, quite excitedly, making notes on the suggestions made for safe de-potting of the 'ol black stuff !!
So, there I am, scrolling through the conversations, when Ian Wiebkin comes into the Frame (!) Halfway through his message, he mentions selling-up his modules to someone else. That was the moment I come to realise who he was refering to.......ME !!!
Spooky...I might even say (!)
Well, he did mention to me that someone down here in Bridgend had bought some other modules off him, and had managed to de-pot the lovely black stuff, and put a diagram together, but I never managed to find out the identity of that person, sadly!
Ian's description of the sound he heard in the demo really impressed me when I spoke to him over the phone....so much so, that I never forgot his words concerning his description of the monoblocks. 'As good as valves in the top end' was one such remark, if I remember correctly.
Anyway, enough of my ramblings.....If only we could get these babys to perform effectively & reliably, it would be a great accomplishment.
Later,
-Andy-
Hi All ....
Well, after just siting down at the p.c (not being able to get any kip) I decided to do a search on Les Sage and see if anyone had continued an interest in his work.
Well, I was amazed to see the number of hits that Google brought up, and especially the threads on this Forum!
I was really interested in knowing what chemical to use to be able to de-pot the Sage modules
, and was, quite excitedly, making notes on the suggestions made for safe de-potting of the 'ol black stuff !!
So, there I am, scrolling through the conversations, when Ian Wiebkin comes into the Frame (!) Halfway through his message, he mentions selling-up his modules to someone else. That was the moment I come to realise who he was refering to.......ME !!!
Spooky...I might even say (!)
Well, he did mention to me that someone down here in Bridgend had bought some other modules off him, and had managed to de-pot the lovely black stuff, and put a diagram together, but I never managed to find out the identity of that person, sadly!
Ian's description of the sound he heard in the demo really impressed me when I spoke to him over the phone....so much so, that I never forgot his words concerning his description of the monoblocks. 'As good as valves in the top end' was one such remark, if I remember correctly.
Anyway, enough of my ramblings.....If only we could get these babys to perform effectively & reliably, it would be a great accomplishment.
Later,
-Andy-
Hi Andy
I used Dichloromethane. Probably from RS.
I think it was made by Robnor Resins.
It took a week to de-pot the amp.
The chemical takes a few hours to dissolve a 1mm layer of the epoxy, then YOU have to scrape away all the sand content that it held together to expose more smooth resin underneath.
Components don't like the stuff so measure value as soon as you have acces to both ends (snip one end free for accuracy).
Which amp are you going to de-pot?
Good luck
Regards
Andy
I used Dichloromethane. Probably from RS.
I think it was made by Robnor Resins.
It took a week to de-pot the amp.
The chemical takes a few hours to dissolve a 1mm layer of the epoxy, then YOU have to scrape away all the sand content that it held together to expose more smooth resin underneath.
Components don't like the stuff so measure value as soon as you have acces to both ends (snip one end free for accuracy).
Which amp are you going to de-pot?
Good luck
Regards
Andy
Hi Andy - Thanks for the qwik reply !!
Well, I believe I have the Supermoss 500 modules (one working, one dead !!)
I had been previously told to use "Nitromethane", which is used as model aircraft fuel. I bought some of this, but then went no further as the info & support was somewhat 'limited', and I had no previous experience with reverse-engineering pwb modules.
I must say that I'm quite surprised at the protracted effort required to remove the potting compound, but I think I'll give it a go at least.
I don't know if anyone reading this knows anything, but I'm looking for a cct diagram for the Kelvin Labs M60 Monoblock power amp., again I've got one working and one dead - the dead one has the o/p devices blown and would like some schematic info on it. Also, I'd like to make a pair of new pwb's for the same units...
Returning to the Supermoss saga....I had some info regarding a Cambridge contact called 'Jon Nicoll', that knows of some guys that also de-potted some other modules. Anyone know of this person?
Seems strange to me that all technical info Les produced has gone to ground (so to speak). I wonder if the info has been bought-out by some manufacturer that doesn't want the designs available commercially ???
Just like the match that could be repeatedly re-lit !?!?!
Kind regards,
-Andy-
Well, I believe I have the Supermoss 500 modules (one working, one dead !!)
I had been previously told to use "Nitromethane", which is used as model aircraft fuel. I bought some of this, but then went no further as the info & support was somewhat 'limited', and I had no previous experience with reverse-engineering pwb modules.
I must say that I'm quite surprised at the protracted effort required to remove the potting compound, but I think I'll give it a go at least.
I don't know if anyone reading this knows anything, but I'm looking for a cct diagram for the Kelvin Labs M60 Monoblock power amp., again I've got one working and one dead - the dead one has the o/p devices blown and would like some schematic info on it. Also, I'd like to make a pair of new pwb's for the same units...
Returning to the Supermoss saga....I had some info regarding a Cambridge contact called 'Jon Nicoll', that knows of some guys that also de-potted some other modules. Anyone know of this person?
Seems strange to me that all technical info Les produced has gone to ground (so to speak). I wonder if the info has been bought-out by some manufacturer that doesn't want the designs available commercially ???
Just like the match that could be repeatedly re-lit !?!?!
Kind regards,
-Andy-
SuperMOS DIY
Did anyone get any further with building their own SuperMOS?
I too had a mind to reverse engineer one of these things several years ago and placed an advert in many of the popular electronics mags to see if anyone had one of these for sale.
Can't believe it's taken so long for details of this circuit to become public. I must admit, having seen it and recognised it as a classic LTP with class A/B output, I'm a little upset...
But the point is, I suppose if one of these has since been built to verify the THD, slew rate and damping factor then I suppose the hyped-up tech material content can be forgiven...
Did anyone get any further with building their own SuperMOS?
I too had a mind to reverse engineer one of these things several years ago and placed an advert in many of the popular electronics mags to see if anyone had one of these for sale.
Can't believe it's taken so long for details of this circuit to become public. I must admit, having seen it and recognised it as a classic LTP with class A/B output, I'm a little upset...
But the point is, I suppose if one of these has since been built to verify the THD, slew rate and damping factor then I suppose the hyped-up tech material content can be forgiven...
Well, this is amusing ...
I happened to do a brief search of t'interweb looking for information the the Les Sage amp, and get here.
I am the 'Jon Nicoll' mentioned in this thread as a contact in Cambridge (tho' I now live near Brighton). I'm also the 'Friendly Chap' Ian Wiebkin mentions, and the scanned schematic and hand-written page comes from me. I thought your name looked familiar, Ian ;-)
I can't add a lot to what is written here. Back in the late eighties, early nineties, I had one SuperMos module and wanted to either get hold of another, or build something similar. I had early access to the internet and like someone else here I also did a patent search on Les' name, with little joy.
Later on, around the mid-nineties, I was quite into amp design - I am responsible for some of the 'Neil McBride' Naim clone PCBs that may still be around. I was also based in Cambridge which has a lot of bright people around. I tracked down a guy who me had who de-potted the unit and drew that schematic (it wasn't me). He was more 'green-fingered' on the analogue side than me and had a very nice pair of Sage amps. We spend a mildly drunken evening (on my part, at least ;-/) listening and chatting, to much the same ands as this thread - how did he have the cheek, etc. etc.
I also had heard that Les killed himself. I think this information came from an ex-hifi manufacturer I know, and so won't name. One can make up a story of how this might have come to pass, but it would only be a story.
Apart from the various scans above, I do have some other articles from Les Sage - I think from amateur DIY magazine 'Common Ground'. There were some things he wrote there that raised my suspicions somewhat, even before I got to learn more about what was under the hood of the SuperMOS amps. However they all makes interesting reading, if only historically. If there's demand for it I don't mind scanning the stuff in.
It's also interesting to hear how consistently highly the Sage amps were rated, in spite of the (assumed) fibs about the technical spec. It would be good to speculat, or learn, a bit more about why this might have been so.
Anyway, nice to see some of this information out there, and hello to anyone who knows me. I don't have much time for hifi building at the moment ;-(, but the time may come again....
Cheers
Jon N
I happened to do a brief search of t'interweb looking for information the the Les Sage amp, and get here.
I am the 'Jon Nicoll' mentioned in this thread as a contact in Cambridge (tho' I now live near Brighton). I'm also the 'Friendly Chap' Ian Wiebkin mentions, and the scanned schematic and hand-written page comes from me. I thought your name looked familiar, Ian ;-)
I can't add a lot to what is written here. Back in the late eighties, early nineties, I had one SuperMos module and wanted to either get hold of another, or build something similar. I had early access to the internet and like someone else here I also did a patent search on Les' name, with little joy.
Later on, around the mid-nineties, I was quite into amp design - I am responsible for some of the 'Neil McBride' Naim clone PCBs that may still be around. I was also based in Cambridge which has a lot of bright people around. I tracked down a guy who me had who de-potted the unit and drew that schematic (it wasn't me). He was more 'green-fingered' on the analogue side than me and had a very nice pair of Sage amps. We spend a mildly drunken evening (on my part, at least ;-/) listening and chatting, to much the same ands as this thread - how did he have the cheek, etc. etc.
I also had heard that Les killed himself. I think this information came from an ex-hifi manufacturer I know, and so won't name. One can make up a story of how this might have come to pass, but it would only be a story.
Apart from the various scans above, I do have some other articles from Les Sage - I think from amateur DIY magazine 'Common Ground'. There were some things he wrote there that raised my suspicions somewhat, even before I got to learn more about what was under the hood of the SuperMOS amps. However they all makes interesting reading, if only historically. If there's demand for it I don't mind scanning the stuff in.
It's also interesting to hear how consistently highly the Sage amps were rated, in spite of the (assumed) fibs about the technical spec. It would be good to speculat, or learn, a bit more about why this might have been so.
Anyway, nice to see some of this information out there, and hello to anyone who knows me. I don't have much time for hifi building at the moment ;-(, but the time may come again....
Cheers
Jon N
Hello everybody, this is obviously a very old thread so I am not sure if there is much point in this contribution. It's really a bit of extra background.
I came across Sage Audio a few years ago, and I now believe that Les was the same Les that I worked with as an apprentice at Thorn Edmonton in the 1970's.
At that time Les was living with his parents and running a large mobile disco outfit. His main claim to fame was that he had taken the 'Project 60' circuit and by adding additional drivers and output devices managed to get circa 1KW out of it, two of these amps powered his disco setup. At the time this sounded quite clever (we were 16 at the time!), although I never heard the amp!
I gave Les a lift home a few times and he was a slightly strange personality and certainly not someone that you would consider being part of the disco scene! How technically competant he was I would not like to say, but to my knowledge he did not persue a path into electronics design, at least not with Thorn.
Having looked at the schematic of this module and the claims made I have to say that I am saddened, but not surprised. The potting compound was perhaps necessary but not for the reasons we all assumed.
Needless to say I was sorry to hear of his death at a relatively early age as he had always been approachable and friendly to his work mates. If anyone has any information on the circumstances I would be pleased to hear from them.
I came across Sage Audio a few years ago, and I now believe that Les was the same Les that I worked with as an apprentice at Thorn Edmonton in the 1970's.
At that time Les was living with his parents and running a large mobile disco outfit. His main claim to fame was that he had taken the 'Project 60' circuit and by adding additional drivers and output devices managed to get circa 1KW out of it, two of these amps powered his disco setup. At the time this sounded quite clever (we were 16 at the time!), although I never heard the amp!
I gave Les a lift home a few times and he was a slightly strange personality and certainly not someone that you would consider being part of the disco scene! How technically competant he was I would not like to say, but to my knowledge he did not persue a path into electronics design, at least not with Thorn.
Having looked at the schematic of this module and the claims made I have to say that I am saddened, but not surprised. The potting compound was perhaps necessary but not for the reasons we all assumed.
Needless to say I was sorry to hear of his death at a relatively early age as he had always been approachable and friendly to his work mates. If anyone has any information on the circumstances I would be pleased to hear from them.
Reply to audiopip
Hi audiopip.
Very glad you posted with this info.
Yes it is the same Les that you worked with as an apprentice at Thorn Edmonton in the 1970's. He told me about his work at Thorn/Ferguson etc. In fact he was still using a Ferguson PreAmp/Tuner to feed his SuperMos Amps at home in his lounge, that he said he helped design.
Those 1kW amps he made and large mobile disco must have been quite impressive for the early 70's. It would have been more powerful than just about any, if not all, nightclubs in the UK back then, Wow ! I wonder what, how many, speakers he used, and if he designed/built the cabinets too ?
No he wasn't the type of person you would imagine running a disco lol, because he was quite shy for one thing. I think his enthusiasm for electronics/audio fired him up, so he put his efforts in producing what he managed to achieve, by the sounds of it.
I have to say, i don't recall him mentioning this aspect of his life, but that doesn't mean it's not true of course. Could be i've forgotten ? I'm sure i would have remembered though !
I've posted in the other Les Sage SuperMos thread you also posted in http://www.diyaudio.com/forums/solid-state/148713-les-sage-audio-new-revelations.html#post2237020
Any info on either Les and/or SuperMos etc by others would be most welcome, even if it's some time from now, as it all helps.
Regards
Zero D
Hi audiopip.
Very glad you posted with this info.
Yes it is the same Les that you worked with as an apprentice at Thorn Edmonton in the 1970's. He told me about his work at Thorn/Ferguson etc. In fact he was still using a Ferguson PreAmp/Tuner to feed his SuperMos Amps at home in his lounge, that he said he helped design.
Those 1kW amps he made and large mobile disco must have been quite impressive for the early 70's. It would have been more powerful than just about any, if not all, nightclubs in the UK back then, Wow ! I wonder what, how many, speakers he used, and if he designed/built the cabinets too ?
No he wasn't the type of person you would imagine running a disco lol, because he was quite shy for one thing. I think his enthusiasm for electronics/audio fired him up, so he put his efforts in producing what he managed to achieve, by the sounds of it.
I have to say, i don't recall him mentioning this aspect of his life, but that doesn't mean it's not true of course. Could be i've forgotten ? I'm sure i would have remembered though !
I've posted in the other Les Sage SuperMos thread you also posted in http://www.diyaudio.com/forums/solid-state/148713-les-sage-audio-new-revelations.html#post2237020
Any info on either Les and/or SuperMos etc by others would be most welcome, even if it's some time from now, as it all helps.
Regards
Zero D
Hi Zero D,
Ah yes I had forgotten the Ferguson connection, in fact he may have well gone to Ferguson TV first. By the late 70's the Ferguson stuff was going down the badged 'c**p' route but Goodmans were still quite respected with the Module 80, 90, Goodmans 110 and finally the 150. They were based over Romford way I think, so Les may have gone to them.
I had various friends involved with the design of those later Goodmans products and owned a 110 for a while and had borrowed a 150. The 150, rated 75W/ch was very good for the time, still probably quite good even now, but the writing was on the wall for Goodmans by the time that was launched. A great shame as they made some very good stuff prior to Thorn acquiring the brand.
Needless to say I lost touch completely with Les mid way through 1974.
Anymore info background on Les much appreciated.
Ah yes I had forgotten the Ferguson connection, in fact he may have well gone to Ferguson TV first. By the late 70's the Ferguson stuff was going down the badged 'c**p' route but Goodmans were still quite respected with the Module 80, 90, Goodmans 110 and finally the 150. They were based over Romford way I think, so Les may have gone to them.
I had various friends involved with the design of those later Goodmans products and owned a 110 for a while and had borrowed a 150. The 150, rated 75W/ch was very good for the time, still probably quite good even now, but the writing was on the wall for Goodmans by the time that was launched. A great shame as they made some very good stuff prior to Thorn acquiring the brand.
Needless to say I lost touch completely with Les mid way through 1974.
Anymore info background on Les much appreciated.
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