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previous: Steve Ahola Re: Mesa "special requirement" power tubes - long -- 7/10/2000 4:54 AM View Thread

Groove Tubes

7/10/2000 12:50 PM
Ray Ivers
Groove Tubes
As I've mentioned in other posts, I've been a Groove Tubes dealer since 1987, and have been repeatedly told by them that they don't care what I sell the tubes for; I get them for 1/2 list, and I usually sell them for list or slightly below and include a free bias, telling my customers that if they look around they may be able to save some money buying them elsewhere. I agree that the store prices do seem 'set in stone'; I think this must be because the stores feel they can get that money for them, because it's surely not because Groove Tubes demands it of them.  
I've noticed after installing/biasing/power-testing many sets of Groove Tubes that they really do seem to clip symmetrically as a set (in addition to having close DC-matching), unlike DC-matched-only tubes which may (or may not) do the same. I feel that DC-matching tubes is mainly useful to prevent large disparities in quiescent plate dissipations, and to avoid output transformer saturation; it really doesn't tell you what the tubes are going to do at full power. The Groove Tube method of matching seems to me to result in a better overdriven sound from any given set of power tubes. Whether or not this is worth the higher list price is an individual decision for each potential customer. My viewpoint is biased - I'm a dealer, have always received good service from them, and get the tubes for pretty much the same price as other tube matchers charge - but I still feel that Groove Tubes are matched in an audibly-superior way. The little bits-and-pieces info on this method I've been able to glean over the years indicate that the Groove Tube numbering system indicates different thresholds of onset of current saturation - so it's not really full cutoff-to-max-dissipation characteristic-curve testing, but a lot closer to that 'ideal' than DC idle current matching. And with Groove Tubes, if you don't like the tubes' sound you can bring them back within a week and try another tube type and/or rating number, which has always seemed like a good deal to me. Yes, I wish they weren't so expensive - but that's largely due to the retail outlets' markup, not Groove Tubes themselves.  

R.G. Adjusting DC *and* AC matching -- 7/10/2000 2:06 PM
Stephen Conner DC matching of tubes -- 7/10/2000 2:09 PM
Steve Ahola Re: Groove Tubes -- 7/12/2000 5:27 AM