Papworth TVA8

[southall-1998]

I recall in my father, owning one in 2003. Lovely sounding little beast!

Can some remember if the TVA8 is auto-bias?

S.

[walpurgis]

Dunno about the biasing, but it's a great amp, renowned for sounding very good. I'd certainly like to try one in my system.

[YNWaN]

If it's the TVA I'm thinking of (manual bias) a friend had two about twenty five years ago (TVA were already defunct even then). They did sound good but one of them eventually caught fire when he was making a cup of tea and that was the end of that.

[petrat]

If it's the TVA I'm thinking of (manual bias) a friend had two about twenty five years ago (TVA were already defunct even then). They did sound good but one of them eventually caught fire when he was making a cup of tea and that was the end of that.

No, that's a TVR you're thinking of ...


http://i1233.photobucket.com/albums/ff384/petrat56/Mobile%20Uploads/13358128_large_zpsoqjftrjz.jpg (http://s1233.photobucket.com/user/petrat56/media/Mobile%20Uploads/13358128_large_zpsoqjftrjz.jpg.html)

[Haselsh1]

Would really love a pair of M100 monoblocks like the ones for sale at the Hi-Fi Emporium at the moment. A lot of money re-valving though and I do not know about the biasing.

[YNWaN]

No, I'm definitely thinking of Papworth TVA - though their reputation for questionable build did parallel that of TVR :). Rather like TVR they did look great and perform well - just fatally unreliable unfortunately :(.

[topoxforddoc]

I remember TVA too from the 80s. They were renowned for sounding good. Mark is right though - there were reports of spontaneous combustion. I would certainly get a TVA checked over properly, if I was offered one now.

[SquireC]

The TVA's that caught fire were the original TVA's. Papworth bought them out and changed the design and they were/are perfectly safe.

As for the M100's, changing the valves will cost a few Bob from the original Edicrons, but worth it. Biasing can be done for each valve but is probably not necessary if you buy matched quads. But if you need to check, Papworth will do that for you.

[Arkless Electronics]

No idea about the baby ones Shane mentions but most of the range, including the M100 monoblocks, are designed by Tim de Paravacini and are almost identical in design to the EAR 509 etc (different output valves obviously). These are fixed bias and the two internal bias controls adjust each pair of EL34's. There are a pair of bias monitoring points inside and one adjusts for 1V at each test point.
Nice amps, very solidly built. Unfortunately I did find a bit of crossover distortion as they are not class A but distortion is low overall at about 0.05%.
A very interesting design with cathode as well as anode drive to the OPT's, bootstrapped drivers and transformer windings providing feedback to two earlier stages... one of the most un-upgradeable or modifiable amps I've ever worked on! Every aspect of the amp is completely tied in to the OPT which connects to virtually every earlier stage!

[petrat]

Rather sparse website (last updated 2005!), but company information section is quite interesting .... http://papworthaudio.co.uk/redrange.html

[Spectral Morn]

No, I'm definitely thinking of Papworth TVA - though their reputation for questionable build did parallel that of TVR :). Rather like TVR they did look great and perform well - just fatally unreliable unfortunately :(.

TVA amps had a reputation as being very unstable and catching fire was not unheard of. Rebuilt with the issues solved probably ok, but I personally wouldn't have the gift of one - I would be afraid to switch it on. I am talking original of course, as I have no experience of Papworth.

[YNWaN]

Looking at the Internet a bit I think the amp I am thinking of was the TVA-1, I remember they used four KT88s - lovely things - apart from the fire part :).

[Arkless Electronics]

Michaelson and Austin TVA-1-Export (yes that Michaelson) was the top beasty and probably the one people are thinking of... Rave reviews at the time (as in "probably the best amplifier in the world") as it was just when valve amps were starting to take off again in this country and there was not much about other than second hand Radford's, Leaks etc plus Beard. About 1979 IIRC.
As too them catching fire well I find it highly unlikely... probably an urban myth. Ceasing to work accompanied by some smoke.... yes quite possibly. Nearly all electronic components and materials used in electronic construction are rated to be non flammable and the casework was steel!

[YNWaN]

I'm not repeating an urban myth. Perhaps my friend exaggerated slightly (I don't know), but I was told this tale first hand by a very good friend who did own two of them. God knows I spent enough time listening to endless Zapa through them to know - quite put me off for life!

[jandl100]

Would really love a pair of M100 monoblocks like the ones for sale at the Hi-Fi Emporium at the moment. A lot of money re-valving though and I do not know about the biasing.

What Papworth M100?

Nah.
I had a pair.
I had them checked over by the Pap guy near Cambridge. Cor, that was a drive and a half from near the Welsh border. Nice guy, can't recall his name.

But they are really, seriously, boring amps. :zzz:
imo.
Gorgeous lookers, mind.
I've come across people who love them, though. It takes all sorts to make a world, don't it.

I lost a £mint on them. :doh:

[YNWaN]

Jerry, my experience is that some people genuinely prefer very bland and undynamic audio - weird, but it takes all sorts I guess.

[Spectral Morn]

Michaelson and Austin TVA-1-Export (yes that Michaelson) was the top beasty and probably the one people are thinking of... Rave reviews at the time (as in "probably the best amplifier in the world") as it was just when valve amps were starting to take off again in this country and there was not much about other than second hand Radford's, Leaks etc plus Beard. About 1979 IIRC.
As too them catching fire well I find it highly unlikely... probably an urban myth. Ceasing to work accompanied by some smoke.... yes quite possibly. Nearly all electronic components and materials used in electronic construction are rated to be non flammable and the casework was steel!

I know two people that had them catch fire and I recall reading an account of one going up in a demo room. Yes it was the TVA1. To be clear I have no experience or knowledge of Papworth amps.

[petrat]

What Papworth M100?

Nah.
I had a pair.
I had them checked over by the Pap guy near Cambridge. Cor, that was a drive and a half from near the Welsh border. Nice guy, can't recall his name.

But they are really, seriously, boring amps. :zzz:
imo.
Gorgeous lookers, mind.
I've come across people who love them, though. It takes all sorts to make a world, don't it.

I lost a £mint on them. :doh:

I visited a dealer back in the 90s, who absolutely raved about them. He had his demo pair in his home system, so on my next visit he brought them to the shop especially for me to hear them. Despite them sounding just like my great aunt's stereogram, he was very insistent that they were the best he'd ever heard. It was rather a difficult situation tbh, and I never went back after that.

[jandl100]

What?!
We agree on something audio-related, Peter?

I feel faint, I'll have to sit down for a bit! :D

[Arkless Electronics]

Well folks I continue to regard it as urban myth... there is nothing flammable and people tend to hugely exaggerate when things go bang!

[southall-1998]

Well folks I continue to regard it as urban myth... there is nothing flammable and people tend to hugely exaggerate when things go bang!

I think you mean kablammo!

:D

S.