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Audio Innovations Valve amps

hi can any one help, im a bit confused as to what valves to buy to replace the ecc82's in my series 1000 mk 111 i see on here ecc802's are recommended would that be the same of eccc83's.also i took the valves thinking they were all the same ,now i dont know what sequence to put them back in any help would be gratefully received
 
The two central valves are ECC83's the two outer ones ECC82's.

I just happen to like the JJ ECC803 and ECC802's but there are plenty of other new & NOS options out there at a whole range of prices.
 
thanks very much for you advice your a star sir. i have another question for you if you dont mind , the toggle switch on the the back of the amps ,what is the best position to have them at up or down ? im looking to replace my pre amp in the near future its an audiolab 8000c would anyone have any advice as to what preamp suits the 1000 mk 111's the source is an audiolab 8000cdm and 8000dax
 
if I recall, that was an earth isolate switch which allowed the internal audio circuitry to be 'floated' while the chassis remained tied to earth. I don't think there actually is a 'better' position for sound quality. It was just that the way some pre-amps were earthed meant that it was sometimes desirable to 'float' one or both of the monos to avoid hum caused by potential earth loops.

The input sensitivity of the Series 1000 Mk3 was still fairly high so you would need a quiet pre-amp preferably without too much gain. Its a question worth posting on this forum & one that will definitely elicit plenty of diverse opinion.

Of the passive variety I've enjoyed auto former based volume controls from the likes of Intact Audio and Tribute. I'm less convinced by transformer volume controls (TVC's).

An active pre-amp has to be pretty good to compete with such devices when used with power amps with highish input sensitivity. I'm sure your Audiolab will not give much away to many sub £1000 SS pre's as a linestage. Maybe the new Audiolab Dac/Pre will be the answer.

Otherwise, this battery powered BL Audio LP1 seems to be being well received although I haven't yet figured out how it works!
http://www.cattylink.com/page199.html

Or even the old AI L1 might be an affordable option.
 
well now you have given me something to think about i didnt know audiolab were back trading i will have a look at some of the recommendations you posted and thanks again . it a joy to have someone who takes the time to help less knowledgeable people out once again thanks a lot
Robbie
 
Yay!
I have my second audios back from servicing by Mr Wright. It's been a long long time due to capacitor supply problems. Anyhoo - they now have mundorf foil caps, and Sanyo OScons, the diodes are now soft recovery types, and the amps have earth lifts fited. I've also replaced all the input valves with JJs (thanks Puresound) and the power valves with new Sovtek 6B4G's. I've spent about a grand on them all things considered.

They sound horrible, but they need running in. I'll post again in a month or so when they are up to speed.

Craig
 
Hi Pete

Yes i did but i made a right balls up of it ' lol you have heard of the stone age ' iron age ' age of steam etc ' well i am afraid i am in the age of Shoddy.

I think i will write out and post it ' will that be ok .
 
The Voyd Turntable part 1

Voyd Turntables is a small Cheltenham based outfit producing turntables of the highest quality .

These start with the Valdi at £595 , then there's the Voyd at £999 (1199 with split phase psu) and finally a strictly ltd edition Reference at a cool £5000 .

The latter item is made to order and there's a substantial waiting time for delivery due to the fact that the motors used are as rare as hen's teeth.

The turntable reviewed here is The Voyd but with a few optional extras which bring it some way towards being a Voyd reference .

Perhaps The Voyd plus would be an apt name for it.

Entry to the owners club isn't cheap: comprising the motor unit (£895) ref bearing and platter (£352) and ref psu (£1275 inc mass dampers) along with a Helius Cyalene (£1066) and Audionote IO (£895) we'll leave you to do the sums .

Quality of finnish is nothing short of superb. All Voyd turntables look the part, with gorgeous sculpted wooden plinths available in a variety of tree options . Three springs are used to suspend the subchassis, and a fundamental part of Voyd design is multiple motor drive -two motors in the cheaper Valdi deck, three motors in all others.

Designer Guy Adams describes the action of the cartridge stylus acting as a brake as the walls of the record groove try to 'drive' it . The degree of braking depends , in part, on the amplitude (volume) and the frequency (pitch) of the modulation (signal) in the groove. Low frequencies and transients are the most difficult signals to get past the stylus.

When a transient occurs the motor in a conventionally driven sprung-subchassis turntable continues to turn at a constant speed, but initially it is easier for the motor to pull the entire record platter, the subchassis and the tonearm assembly towards itself than to pull the platter and record past the stylus .

This dynamic instability is happening all the while a record is playing - and the result, says Guy Adams , is that we're not acurately retrieving all the information content of the record groove, especially in the areas of low level detail and dynamic attack.

All Voyd decks employ acrylic platters for good 'impedance matching' between record and platter (a controversial subject, this : its one thing for unwanted vibrational energy to be effectively transferred from the vinyl disc to the platter, but then where does this energy go?); however what we have on this deck as one of the optional upgrades is the platter from the reference turntable. This is machined from highly expensive polycarbonate sheet (Lexan) which is claimed to improve upon acrylic by its ability to dissipate heat as energy more readily .

This provides a more inert platform for the record, thus the attack and decay profiles are improved. The £352 buys not just the platter from the reference deck but also an improved main bearing to go with it. This has a diamond lapped thrust pad along with a tapered , hardened silver steel shaft to provide an exceptionally fine running clearance.

Part 2 to follow
 
Voyd Turntable part 2

Then there's the Reference psu . This unit , like the platter and bearing, is identical to that used in the Reference turntable . Its a high voltage (up to 150v rms) 350VA twin phase unit , housed in a substantial rack mounting case-and at first glance it could be easily mistaken for a fairly meaty power amplifier! Front panel switches control power on/off and speed selection between 33 and 45 rpm.

Guy Adams describes the technology used in the power supply as ' state of the art '.
The use of output transformers allows high voltages and power to be maintained accurately and reliably. The psu operates the motors at twice the speed that they run in the standard deck , giving the drive system four times the inertia. Also the motors can be run in series (parallel in the std deck), allowing several advantages: because the magnetic flux and hence torque is generated by current ,when the motors are connected in series they are all forced to draw the same current and therefore the same flux is generated in the stator of the external rotor papst motor.

This application in a three motor system says Voyd , guarantees that all the motors 'pull' in exactly the same way and therefore the stability of the drive system is further improved.
Within the turntable plinth substantial motor brackets are used to provide a rigid mounting platform for the motors and to control unwanted energy by providing a region of high mass close to the motors. The fitting of these 'mass dampers' by the manufacturer is part of the reference psu upgrade package.

part 3 to follow
 
The Voyd part 3

Sound Quality

It takes little more than the first few bars of music to hear the upgrades to the standard Voyd provide a considerable improvement in sound quality. Late last year i auditioned a standard deck with Cyalene arm and IO Limited cartridge-and it didn't sound as vivid and well-focused as this review deck, despite the fact that this time around i was using a slightly inferior cartridge (the IO ltd is breathtaking, while the ordinary IO is merely wonderful!)

Like the standard voyd only more so, this upgraded deck sounds powerful and authoritative, and in terms of its ability to track dynamic swings in music it is world class .
What the upgrades appear to have done is improve bass control and 'slam' and improve soundstaging . Never before has my system produced such lifelike , out of the box images, and the placement and perspective of sounds within the soundstage were explicit and extremely vivd.

Listening to this analogue front end is always a rewarding experience . The musical performance is colourful and dramatic, and unlike some decks which appear to throw detail and excitement at the listener , The voyd never causes stress or fatigue . This deck is just the tonic for systems which sound bland or over damped.

Conclusions

Aimed clearly at enthusiasts and music lovers who demand the best possible sound from vinyl records, The Voyd is a beautifully presented turntable which puts many brittish hifi products to shame. Not only is this a piece of furnature which you'd proud to have in your home , but the sound it presents is 1st rate too. And the upgrade options have pushed it onto a higher plane.

What's nice for existing Voyd owners is that the reference upgrades are retrofitable . Also enthusiasts may wish to start with a standard deck -perhaps with a Rega arm and something like a Goldring Eroika- and then upgrade over the years to a deck which is not far short of the full blown reference. its good news for consumers because they are never left with an out of date product, and its good marketing because it inspires strong brand loyalty from customers.

Turntable sound is a subjective business , and all the magazine commentators have there favourite models. What is indisputable about the Voyd however, is that it is clearly one of the finest turntables available anywhere in the world at any price. If the price ticket won't prove a stumbling block I strongly recommend you investigate further.
Playing records on a turntable of this quality is a real treat.

Review by John Bamford July 1989.
 
Hi, I am a complete newbie to the AI valve amps and have just bought myself an S700 which doesn't seem to get a lot of mention here.

So, a few (maybe obvious) questions if you wouldn't mind helping ?

How does the S700 compare to the more popular S500 sonically and schematically ?

Any known problems, obvious improvements ?

Puresound (Guy) I would appreciate a copy of the schematic if that's OK, I will pm you.

Thanks for your help.
 
A great upgrade for the S700 is a Border Patrol valve rectified choke input filter psu.

A lot of dosh though , but boy does it sound good with it ' Gary Dews did an A-B at a hifi show and difference is not subtle .
 
no problem re the schematic.

The 500 did have a rather fuller, richer quality than the 700. Many 500's had the earlier Hinchley made transformers which were very nice. There was also some frequency compensation in the circuit although I'd need to look again at the schematic to confirm that. The 500 could sound very engaging with some speakers but occasionally overblown with others.

The main problem could occur with EL34 output valves overheating, locking up & drawing too much current which would take out the cathode resistors & by-pass caps. The Sovtek (now EH) EL34's were less prone to it than any of the chinese types and were eventually fitted as standard.

People quite often fit Russian made 5881's to good effect which aren't afflicted by the same kind of failure.

(Incidentally this kind of pentode overheating wasn't reserved for AI or the EL34. Leak had terrible failure problems with earlier Stereo 20's and EL84's which were mostly resolved by turning it all down a little)
 
this time it's the Alto, the non-valve and as such lone, but extremely good, ss AI amp> i wonder if someone (Guy?) can tell whether the coupling caps are the 220uF ones? i'd love (and believe need) to change them, and want to make sure, plus need suggestion on a brand that would work there as 'the best' - please advise
 
2200uF @ 63v iirc We actually did quite a bit of listening to different makes of cap in that particular position and ended up with two preferences which were either a Nichicon or the supposedly lesser grade (blue) BHC one. If you really do need to change them, it'd be interesting to try some Elna Cerafine or Silmic there if you can find the value.
 
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