pure sound
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That's encouraging, the S1000 Mk3 was a really nice amp with exceptional output transformers.
Audio Innovations Valve amps
- Thread starter BlueYeti
- Start date
I fell in love with them when I first heard them. They sound not unlike a well fettled Leak Stereo 20, only with a heap more power of course.
I've left them ticking over while I'm doing the ironing, I reserve the right to say each time I go in the room they sound better each time.....until I can properly check it out!
I am looking forward to introducing the new tube DAC to them in the future, but that really will have to wait until I've moved house
Steve
tomaneporto
Member
I spent last nights listen my new JJ ECC802 and 803 valves (nice pure sound recommendations).
Well my old ones are 5/6 years old!
The JJ put everything in is right place, very warm, not so hisssssssssss.
But I think they need a few more hours to show all predicates.
Regarding to the PSU, next Sunday I will listen a pair of changed AI1000 (lets see if my ears love them or not).
Rgs
Tomane
Well my old ones are 5/6 years old!
The JJ put everything in is right place, very warm, not so hisssssssssss.
But I think they need a few more hours to show all predicates.
Regarding to the PSU, next Sunday I will listen a pair of changed AI1000 (lets see if my ears love them or not
).Rgs
Tomane
I had a 500 (20W integrated with the perspex top) from 1986 until 2005. Sound wise it was for its time a landmark product and I never regretted buying it. It had a lovely, clean, open finely textured sound with good grip and dynamics but its comfort zone was medium/loud or lower - it was no pile driver, as would be expected, and would harden up quite a lot if made to sweat. Staging was not its strong suit.
I loved it and found it very difficult to replace when I decided to go for something more powerful. I preferred it to a 282/Hi/250 at home and it was finally beaten by the Graaff GM50, in many ways the same - but more.
It had a reputation for eating output valves and it did indeed go bang once. AA were still trading then - as Audio By Design IIRC and they fixed it for just the carriage charge. It was about two years old at the time. During the mid 90s and 00s Boarder Patrol did a service and one repair, replacing a noisy volume pot. They also modified it to not self destruct but after the first problem it didn't happen again. Good safety net though. There was a small but active community on the Web which majored mainly on experimentation with different valve makes and types and over the course of my ownership many bottles were swapped, some with good results, some not. I think in wide circles it had a flaky reputation but mine ran fine apart from the one problem early in its life and it did sound very good indeed.
For what that's worth.
I loved it and found it very difficult to replace when I decided to go for something more powerful. I preferred it to a 282/Hi/250 at home and it was finally beaten by the Graaff GM50, in many ways the same - but more.
It had a reputation for eating output valves and it did indeed go bang once. AA were still trading then - as Audio By Design IIRC and they fixed it for just the carriage charge. It was about two years old at the time. During the mid 90s and 00s Boarder Patrol did a service and one repair, replacing a noisy volume pot. They also modified it to not self destruct but after the first problem it didn't happen again. Good safety net though. There was a small but active community on the Web which majored mainly on experimentation with different valve makes and types and over the course of my ownership many bottles were swapped, some with good results, some not. I think in wide circles it had a flaky reputation but mine ran fine apart from the one problem early in its life and it did sound very good indeed.
For what that's worth.
I'm enjoying by 1000 monoblocs. Since replacing the valves and coupling capacitors the staging, which was there just not in oodles, is now significantly improved and the overall detailing is getting more obvious the longer I run in those new valves. The mixture of Sovteks and Precisions were tired I'm sure, good, but tired.
I'm close to getting to the bottom of these amps eating valves. One further series of tests could deliver the answer those still with these amps could be waiting for. But it'll be a few weeks now as I move house in a fortnight and that comes first now. Suffice it to say I don't believe this "inherent problem with EL34" guff. Many amps use this valve with no issues at all and it was that that prompted the research. I do however believe there is an inherent problem with the amplifier in more general terms, but before I say anything, I need to test the theory. Should my theory be founded, I shall be asking if anyone close to me has other AI amps I can test to further prove my theory.
Meanwhile, I shall be keeping the use of my monoblocs to a minimum for a while. I think it's testament to the EL34 that it lasts as long as it does in the AI amps considering the fact that........well.......later!
Harry: One line in your text: "They also modified it to not self destruct but after the first problem it didn't happen again." was what made me relook at what the problem could have been, and with pure sound's kind donation of the schematics has guided me. For now I'm just going to suggest the use of a sizeable resistor may just cure everyone's "inherent EL34 internal shorting problem"!
Will report back soon!
I'm close to getting to the bottom of these amps eating valves. One further series of tests could deliver the answer those still with these amps could be waiting for. But it'll be a few weeks now as I move house in a fortnight and that comes first now. Suffice it to say I don't believe this "inherent problem with EL34" guff. Many amps use this valve with no issues at all and it was that that prompted the research. I do however believe there is an inherent problem with the amplifier in more general terms, but before I say anything, I need to test the theory. Should my theory be founded, I shall be asking if anyone close to me has other AI amps I can test to further prove my theory.
Meanwhile, I shall be keeping the use of my monoblocs to a minimum for a while. I think it's testament to the EL34 that it lasts as long as it does in the AI amps considering the fact that........well.......later!
Harry: One line in your text: "They also modified it to not self destruct but after the first problem it didn't happen again." was what made me relook at what the problem could have been, and with pure sound's kind donation of the schematics has guided me. For now I'm just going to suggest the use of a sizeable resistor may just cure everyone's "inherent EL34 internal shorting problem"!
Will report back soon!
pure sound
Trade: manufacturer/distributor
schematics sent
tomaneporto
Member
Well by know it's possible for me to talk about the replacement valves ECC82 and ECC83.
Thanks again pure_sound the changes are greater, the new JJ's transform the AI to another level (ok...... the others are a very, very old LOL... but).
The music is now not so "compact", more silence between the notes, more power (I don´t know, how it's possible because I don't change the EL34's ???).
My vandersteens never, never put so much music in the air.
Next step put the PSU's... lets see.
In the time I say something about that.
Always feeling the music...
Thanks again pure_sound the changes are greater, the new JJ's transform the AI to another level (ok...... the others are a very, very old LOL... but).
The music is now not so "compact", more silence between the notes, more power (I don´t know, how it's possible because I don't change the EL34's ???).
My vandersteens never, never put so much music in the air.
Next step put the PSU's... lets see.
In the time I say something about that.
Always feeling the music...
coltrane
electrobaroCKjazzer
a pretty easy, zero financial investment, and GREEEIT upgrade has so far been hidden inside my AI S400.2 amp, but today it has been revealed by chance to my greatest surprise.
what happened was that i - due to pure sound's help - got the schematics for the AI S300.2 and wanted to convert it to 110V operation for a friend, as it seemed manageable from the instructions embedded in the text of the papers. however, as it turned out, at least the S200.1 and .2 power, S300.1 and .2, and the S400.1 and .2 can not work on a different voltage than what is actually written to their backs as the transformers have no taps for a different voltage connection.
having learnt that, i wondered why then there are dotted lines around certain components in the schematics noted as "cut for 120/240V operation". there is a resistor and 2 links to be cut off the circuit noted as such, and then i gave a try to it for the voltage here is 235-238V.
it took only 10 minutes to remove the lid, cut off the pieces, then put the lid back, and switch the amp on. and THEN... believe me, my lil' ol' S400 was transformed into a miraculous wonder machine: presence, transparency, naturalness, details, space, smoothness came out of the speakers in abundance fooling me to believe a new equipment was put into my system without letting me known i dunno what those parts had been doing in the amp, but without them a new lease of live was given to my amp. i phoned some friends owning S300, 400 and 200 amps and suggested them to do the trick - and it worked for all of them, too
thus, if there is anyone here possessing any of the above amps, and have voltage around 230+ V, do the following (all must be done in the PSU; you need ony a cutting pliers, and can do it without being deeply skilled in electronics): cut off the link next to the 0.10R or 0.15R green resistor on the right edge of the pcb, just below the diode bridge, also cut off an other link by the 5401 diode just above the 4700/6800uF caps in the direction of the output transformers, and, finally, cut off the legs of the uppermost of the piggybacking 2 pcs. 220R resistors just in front of the big blue BHC cap in the middle of the PCB. do not forget to remove the stuff and legs, too!
and now, switch the amp on, sit back - and enjoy
upgrade has so far been hidden inside my AI S400.2 amp, but today it has been revealed by chance to my greatest surprise.what happened was that i - due to pure sound's help - got the schematics for the AI S300.2 and wanted to convert it to 110V operation for a friend, as it seemed manageable from the instructions embedded in the text of the papers. however, as it turned out, at least the S200.1 and .2 power, S300.1 and .2, and the S400.1 and .2 can not work on a different voltage than what is actually written to their backs as the transformers have no taps for a different voltage connection.
having learnt that, i wondered why then there are dotted lines around certain components in the schematics noted as "cut for 120/240V operation". there is a resistor and 2 links to be cut off the circuit noted as such, and then i gave a try to it for the voltage here is 235-238V.
it took only 10 minutes to remove the lid, cut off the pieces, then put the lid back, and switch the amp on. and THEN... believe me, my lil' ol' S400 was transformed into a miraculous wonder machine: presence, transparency, naturalness, details, space, smoothness came out of the speakers in abundance fooling me to believe a new equipment was put into my system without letting me known
i dunno what those parts had been doing in the amp, but without them a new lease of live was given to my amp. i phoned some friends owning S300, 400 and 200 amps and suggested them to do the trick - and it worked for all of them, too thus, if there is anyone here possessing any of the above amps, and have voltage around 230+ V, do the following (all must be done in the PSU; you need ony a cutting pliers, and can do it without being deeply skilled in electronics): cut off the link next to the 0.10R or 0.15R green resistor on the right edge of the pcb, just below the diode bridge, also cut off an other link by the 5401 diode just above the 4700/6800uF caps in the direction of the output transformers, and, finally, cut off the legs of the uppermost of the piggybacking 2 pcs. 220R resistors just in front of the big blue BHC cap in the middle of the PCB. do not forget to remove the stuff and legs, too!
and now, switch the amp on, sit back - and enjoy
pure sound
Trade: manufacturer/distributor
iirc (and its a long time ago) there was the provision to run these amps at 220v (for most of Europe) and 240v (UK). If you have nearly 240v then the filaments and ht supply will be happier on the 240v setting.
Probably not more power as such but more gain. I did fiddle about with this but I've long since forgotten which of the small valves I swapped. More gain wasn't much use to me in practice because I couldn't run it past 9 O Clock without it being too lour in my room/system and more gain allowed even less volume control.
Hello again gents.
I thought I'd make a simple change in my set-up to accommodate my 2nd audios when they come back from servicing: short speaker cables and long interconnects. Sounds simple, doesn't it?
No - it isn't. I placed an order with DNM yesterday for some of their long unsheilded ones (I've always been a DNM fan), and today Mr Moorcroft himself, no less, rang me back to say he didn't think it was a very good idea, unless the 2nd Audios are truly zero feedback designs. Most amps are designed to drive a certain amount of cable! He's trying to talk himself out of a sale - he's waiting for me to get back to him with a modified order. You have to admire that. What an excellent gent.
So, can anybody tell me whether the 2nd Audios are truly zero feedback designs, or is there some negative feedback in there somewhere?
Thanks,
Craig
I thought I'd make a simple change in my set-up to accommodate my 2nd audios when they come back from servicing: short speaker cables and long interconnects. Sounds simple, doesn't it?
No - it isn't. I placed an order with DNM yesterday for some of their long unsheilded ones (I've always been a DNM fan), and today Mr Moorcroft himself, no less, rang me back to say he didn't think it was a very good idea, unless the 2nd Audios are truly zero feedback designs. Most amps are designed to drive a certain amount of cable! He's trying to talk himself out of a sale - he's waiting for me to get back to him with a modified order. You have to admire that. What an excellent gent.
So, can anybody tell me whether the 2nd Audios are truly zero feedback designs, or is there some negative feedback in there somewhere?
Thanks,
Craig
Craig,
I cannot guarantee this, but the following link shows both the First and Second Audio amps as zero feedbackdesigns, all marks.
Maybe "pure sound" can help, if not, try firing off an email to David Wright, details within that page.
Steve.
http://www.borderpatrol.net/aiind.htm
I cannot guarantee this, but the following link shows both the First and Second Audio amps as zero feedbackdesigns, all marks.
Maybe "pure sound" can help, if not, try firing off an email to David Wright, details within that page.
Steve.
http://www.borderpatrol.net/aiind.htm
Well, I believe mine are among the very earliest, so I'm taking that as a yes. I've gone and ordered the DNM interconnect (6.5 metres of it!)
David Wright thinks its a good bet, but Mr Morecroft doesn't.
I know its been a few years since I read much about hifi, but long interconnects and short speaker cables was received wisdom a few years back - its the thing that made me think monoblocks were a good idea in the first place!
One thing that continues to surprise me is how we can have a conversation with the real top-bananas regarding these queries, and they take the time to respond! Fantastic! It feels like a real community.
I will let you know how it goes with the long interconnects.
Cheers,
Craig
David Wright thinks its a good bet, but Mr Morecroft doesn't.
I know its been a few years since I read much about hifi, but long interconnects and short speaker cables was received wisdom a few years back - its the thing that made me think monoblocks were a good idea in the first place!
One thing that continues to surprise me is how we can have a conversation with the real top-bananas regarding these queries, and they take the time to respond! Fantastic! It feels like a real community.
I will let you know how it goes with the long interconnects.
Cheers,
Craig
pure sound
Trade: manufacturer/distributor
The Second Audio's were without local or global feedback.
I'm not sure why it would influence Dennis Morecroft's recommendations though. If an amplifier needs to be feedback free to be used with the DNM cable that would have ruled out most types of amplifier. Was he specifying that requirement for interconnects or speaker cables? Speaker cables surely.
I'm not sure why it would influence Dennis Morecroft's recommendations though. If an amplifier needs to be feedback free to be used with the DNM cable that would have ruled out most types of amplifier. Was he specifying that requirement for interconnects or speaker cables? Speaker cables surely.
Mr Morecroft was talking about the wrongness of the received wisdom re: short speaker cables being good. He maintains that amps are designed to drive a certain amount of cable - he talked about resistance but I didn't follow him, so can't relate it here. I do remember he talked about feedback making the amp into an RF device and that the cable would 'damp' it. (apologies if that's nonsense - its hard to remember things that one doesn't understand!)
Anyhoo - the only amps where it isn't necessary to have any appreciable cable length are zero feedback designs, of which there are very very few. SO in general Mr Morecroft does not recommend short speaker cables.
Another completely different reason was the risk of hum being picked up by long interconects. Mr Morecroft maintains that even if the hum isn't audible in itself, it will adversely affect the sound quality your amp produces.
All in all, he was quite resolute in his opinion that long interconnect & short speaker cables are a bad idea.
Unfortunately for me, I can't physically accommodate the amps near the rest of my gear without spending a wad on new supports. £200 on some long interconnects is the cheapest way forward - so I'm going for it as an experiment. If it hums or sounds rubbish, I can always make up several short interconnects from it and think again.
Craig
Anyhoo - the only amps where it isn't necessary to have any appreciable cable length are zero feedback designs, of which there are very very few. SO in general Mr Morecroft does not recommend short speaker cables.
Another completely different reason was the risk of hum being picked up by long interconects. Mr Morecroft maintains that even if the hum isn't audible in itself, it will adversely affect the sound quality your amp produces.
All in all, he was quite resolute in his opinion that long interconnect & short speaker cables are a bad idea.
Unfortunately for me, I can't physically accommodate the amps near the rest of my gear without spending a wad on new supports. £200 on some long interconnects is the cheapest way forward - so I'm going for it as an experiment. If it hums or sounds rubbish, I can always make up several short interconnects from it and think again.
Craig