Valves for Audio Research Ref3 Pre-amp

Hi,
I have recently changed the valves in my Ref3, replacing the 6550 valve in the power supply with a Svetlana 6550 winged C and the five 6H30 valves with some Electro Harmonix gold pin. All valves were purchased from Hotrox here in the Uk. I`m still wondering if I have done the right thing using these and wonder if I should have purchased a full set from Absolute Sounds. I originally spoke to a couple of Ab Sounds dealers and looked at a few forums etc but I found it difficult to be conclusive about what make of valve would have been originally supplied. I went round in circles between Sovtek, Sed & Svetlana. In short, have I done the right thing here? The Sovtek 6550 was only around half the price of the Svetlana that I ended up buying so I assumed it would be a better valve. I was also recommended the Electro Harmonix gold pin.

Opinions seem hugely varied and I`m looking for some clarification here if at all possible.

Many thanks,
Paul.

DaveyF said:

Hi Paul,
How does the Ref 3 sound? If you like it, that's all that matters.
I think the Winged C 6550 is a VERY good tube. Not so enamored of the EH's. However, I'm not sure that a Sovtek or other similar non NOS tube would be much better. If the tubes are quiet and dynamic, that's a big part of the equation, IMHO.

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Hi DaveyF, MEP & Microstrip

Many thanks to you all for taking the time to answer my question.

Please don't misunderstand me here. I'm not getting a bad sound but perhaps there is just a little niggle in the back of my mind. Without trying to use loads of adjectives but overall the sound is perhaps just not quite as enjoyable as it was before. Difficult to explain but it seems it's in the land of "not quite". Not quite as big a sound stage as before, not quite as much bloom, not quite such a firm bottom end and may be not quite as resolved. Just a little of the ease may have gone too. This all sounds bad but I'm really not talking huge amounts.

The new valves have only covered 50 hours and I do wonder if they will settle down. I suppose a couple
of hundred hours would be more of a fair time to be critical.

I did speak to three dealers here, two of them Absolute Sounds dealers and the different advice was quite startling. One of the AB Sounds dealers did actually recommend the EH 630h Gold pin over the valves supplied from Audio Research for being far less costly and stated that there would be absolutely no difference. I was of course picking up strong vibes from this statement that perhaps the Audio Research thing may just be hyped up and a little bit of a rip off.
The 6h30's that I purchased were sold as a matched quad so I assumed that was fine for my requirements. The fifth 6h30 was obviously just purchased as a single.
I am still so curious as to what make of valves would have been supplied to me as replacements from Audio Research. Does anybody know? Most of the time I have spent trying to find out about the valves from the Internet & dealers alike just seems to have taken around in circles and perhaps left me more confused than when I started. So often you see quoted as "the valves supplied by AR" but never is it stated what they actually are. I did request a purchase price for a genuine set from another dealer and never heard back. I just kind of felt like I was on my own with it a bit and so just decided to go my own
way and hope for the best, I.e. Took the advice about the EH gold pins and went with what I considered
to be a good quality 6550 in Svetlana.

Thanks so much to you guys again for your words but I guess I should persevere a little longer and then make a decision on it. Incidentally, if I did decide to try the AR supplied valves, would it make sense to perhaps leave the 6550 alone and just go for the five 6h30. Would these valves have more impact on sound quality than the power valve as they are matched. Again, sorry if I'm showing ignorance here but I
Simply don't know the answer myself.
Kind regards,
Paul.



P.S. Please, could someone answer another question too if possible. Are the Svetlana 6550 winged c that I purchased and the SED 6550 winged c one and the same? Is it just re-badged for sale in the USA as I've noticed you can't seem to buy these in the UK. I have come across adverts that call a valve Svetlana/SED, as if they are the same thing. Again, sorry if I'm missing something obvious here. P.

mep said:

The Svetlana 6550 and the SED 6550 are not the same. New Sensor bought the rights to the Svetlana name and they are selling tubes made by Sovtek as Svetlana tubes. If you want to buy "real" Svetlana tubes, you must buy them from SED. As for your other question, it would be far more critical for you to buy the 6H30 tubes from ARC than to buy just the 6550.

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Ok MEP,thanks for that info. So is it an SED that is supplied as original in the Ref3, or is it a different valve again? Also, just to clarify, you are saying that it would be still beneficial just to buy the five 6h30 valves from AR, ( i'm still curious as to what brand these may be)and perhaps keep the Svetlana 6550? Changing these five would have more of an overall impact on the sound than the 6550?
Many thanks,
Paul.

arnies said:

Hi paul,

I owned a Ref 3 for about 3 years and really enjoyed it. I did try various 6H30 tubes (there really aren't many to choose from). I tried the ARC ones that came with the unit, the EH 6H30 gold pin tubes and also the 6H30DR tubes. To be honest, I could not tell that much difference between any of the 6H30 - if I was pressed, I would probably say the 6H30 DR tubes were slightly richer sounding - but I emphasis "slightly" and are not worth the high dollars at least when used in the Ref 3. As for 6550 tubes, I always stayed with the SED 6550 tube (never tried any others). For me, the most important thing was to change that 6550 every 1300 -1400 hours despite what ARC might say about it lasting 2000 hours. For me, around the 1300-1400 hour mark I could hear the degradation in the sound - it became drier and more analytical. Pop in a new one (keeping the same 6H30 tubes) and the sound came back.

Arnie

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Hi Arnie. Many thanks for your input.
To clarify then, your Ref3 was fitted with an SED 6550 from new? Do you recall what the 6h30's were that came supplied in the unit from new? Would they have been SED also and would this be what I would be getting if I ordered a set from ARC?
Interesting what you say about the life hours of the 6550. I will pay particular attention to this after 1000 hours.
Thanks again Arnie.
Paul

Elberoth said:

I can only echo microstrip comments. I would only buy tubes from ARC as they are VERY closely matched - in most times, more so than any so called 'matched' quad sets available on the net.

It is interesting to note that ARC only matches them after the full 48h burn in is completed. No online retailer I'm aware of does that. After burn in the reject ratio is ... over 50% - only the best ones make it to ARC product. The rest is not beeing thrown away but is beeing sold to ... whoever wants to buy them - mostly online retailers.

I believe the most crucial are the 6H30 tubes. You can buy the 6550 from a local supplier. You can also try one of the vintage 6550s available. In my Ref-3 I have tried the 1950s Black Plate and it brought a considerable improvement over the 6550C. Those tubes are hard to find though and getting really pricey.

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Hi Elberoth. Many thanks for your input.
So, it seems that the real crucial thing here is that the valves from ARC are very closely matched and tested for faults after a 48 our burn in. As you say, if 50% are disposed of then they must be pretty selective.
How would you consider a less than perfect set of 6h30 installed in the Ref3 may effect the sound? Would the sound be generally compromised or would certain aspects suffer more than others?
I can see that MEP is going to be spot on here! It will drive me around the twist wondering about the ARC valves to the point where I will have to buy them, just to be sure.
Also interesting about your 6550. I guess that kind of proves that even this valve in the power supply can effect sound quality then..
I have noticed a valve called SED 6550 Black Sable. It looks to be a treated version of the the standard SED 6550 Winged C. Would you have any thoughts on this valve and could it be even better than the offereing of ARC?
Would be grateful for any comments.
Many thanks,
Paul

whart said:

My experience is dated but:
One of the things about ARC that is to be commended is that they seem to stock parts even for their ancient stuff- I bought my first ARC gear in 1974 or so, and though I finally sold the preamp (SP 3-a-1), I still have the matching amp (Dual 75a). Last year, I ordered not just a full complement of tubes, but new barrier strips for the speaker connections, a set of sheet metal screws to hold down the protective cage, and a few other odds and ends.
I never really tube rolled any ARC gear I had, except for the SP-10 preamp, in which tubes tended to go microphonic. And then, it was really just to find quiet tubes. Like others, I always just bought replacement tube sets for the various amps (none recent, all before the 'Reference series') directly from ARC.
And for years, I had a telephone relationship with 'Leonard' there- a phlegmatic, midwestern guy in the service department who always came through. (I gather he finally retired). Good company, very solid customer support based on 40 years of my experience with them.

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Hi whart. Thanks for taking the time to write here and passing on your experiences. Much appreciated.
I intend to give the valves that I have purchased a full run in time of at least 100 hours and then perhaps make a decision from there. I have since read on various forums that a burn in time for new valves is important with regard to sound quality. Various comments from around the web report just the same aspects of sound quality as I am experiencing with new valves with far better results achieved after a couple of hundred hours usage.
For anyone interested I will re-post at around two hundred hours burn in to share my findings.
All the best to you all for now,
Paul.