philv
11-07-2025, 14:54
Audio innovate s500 valve integrated amplifier.
4 x 5881 power valves.
2 x e88cc.
3 x ecc83.
This has been recapped and serviced by a well known audio tech, firebottle (Alan).
This hasn't missed a beat in the 2.5 years i've had it.
A testament to Alan's good work.
The majority of the caps were replaced with high temp low esr rated caps.
I believe the main smoothing caps were in good condition, tested well and of high quality, and so were retained.
HT voltage was lowered to go easier on he valves.
A 1k2 3w resistor instead of 100r in the screen.
Please see here for info -
https://www.diyaudio.com/community/threads/audio-innovations-500-output-transformer.302268/page-2
I wanted to retain the original character of he s500, whilst at the same time upgrading it's week points, and also ensure reliability.
I didn't want a totally different amp.
Volume pot has been upgraded to a TDk.
The balance pot has been upgraded to audio note.
The 2 switch pots have been upgraded to elma.
The switches and pots on these lovely amplifiers were never high quality.
It has been upgraded to run in either triode or pentode via a switch on the rear.
A couple of small mods internally to ensure reliability and valve liffe.
The mains transformer has been replaced like for like with a new one from the company that acquired the rights to production.
(Majestic Transformers).
As such it is an original s500 mains transformer.
Mains transformers can become noisy after 35 years or so of use.
This amp is now very quiet.
The amp has the wonderful hammond output transformers, with the 4, 8 and 16 ohm speaker taps.
These are better sounding than the non 16 ohm non hammond version.
(not all s500 amps had the better hinckley transformers).
I have changed the knobs and pins that locate the perspex shelf in place.
The knobs are high quality.
I also have the original black knobs and pins.
I have the original box and packaging.
Although this is collection only.
This s500 has been upgraded so as to keep the wonderful sonic signature of the original, whilst at the same time improving on sound quality.
As such, i doubt you will and a better example.
I have used this with various speakers and it has always sounded superb.
If you have a version of ls3/5a (which i am also selling) this push pull valve amp is stunning and hard to beat.
The cost of the upgrades/service/refurb was over £800.
Selling for 1300.
Collection eton wick/windsor.
[Imgur](https://i.imgur.com/aE6tuym.jpg)
4 x 5881 power valves.
2 x e88cc.
3 x ecc83.
This has been recapped and serviced by a well known audio tech, firebottle (Alan).
This hasn't missed a beat in the 2.5 years i've had it.
A testament to Alan's good work.
The majority of the caps were replaced with high temp low esr rated caps.
I believe the main smoothing caps were in good condition, tested well and of high quality, and so were retained.
HT voltage was lowered to go easier on he valves.
A 1k2 3w resistor instead of 100r in the screen.
Please see here for info -
https://www.diyaudio.com/community/threads/audio-innovations-500-output-transformer.302268/page-2
I wanted to retain the original character of he s500, whilst at the same time upgrading it's week points, and also ensure reliability.
I didn't want a totally different amp.
Volume pot has been upgraded to a TDk.
The balance pot has been upgraded to audio note.
The 2 switch pots have been upgraded to elma.
The switches and pots on these lovely amplifiers were never high quality.
It has been upgraded to run in either triode or pentode via a switch on the rear.
A couple of small mods internally to ensure reliability and valve liffe.
The mains transformer has been replaced like for like with a new one from the company that acquired the rights to production.
(Majestic Transformers).
As such it is an original s500 mains transformer.
Mains transformers can become noisy after 35 years or so of use.
This amp is now very quiet.
The amp has the wonderful hammond output transformers, with the 4, 8 and 16 ohm speaker taps.
These are better sounding than the non 16 ohm non hammond version.
(not all s500 amps had the better hinckley transformers).
I have changed the knobs and pins that locate the perspex shelf in place.
The knobs are high quality.
I also have the original black knobs and pins.
I have the original box and packaging.
Although this is collection only.
This s500 has been upgraded so as to keep the wonderful sonic signature of the original, whilst at the same time improving on sound quality.
As such, i doubt you will and a better example.
I have used this with various speakers and it has always sounded superb.
If you have a version of ls3/5a (which i am also selling) this push pull valve amp is stunning and hard to beat.
The cost of the upgrades/service/refurb was over £800.
Selling for 1300.
Collection eton wick/windsor.
[Imgur](https://i.imgur.com/aE6tuym.jpg)