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Thank you everyone for your input. Do you guys ever deal with this vender on eBay.
I asked because they have 100% positive feedback over 9,000 items.
ghosthouse, I will have to call ARC today to find out if my VS60 can do KT120, if not then I will have to get 6550we Sovtek.
Eddie - Should be easy for you to get some decent, matched current production 6550s. For current production, I'd probably go with Kevin Deal at Upscale or Jim McShane.
just fyi - Kevin MIGHT have an issue with selling to you if he knows it's for ARC gear. Seems like I saw something or other about that on his site at one point. I don't recall what his problem with ARC was. It might have had something to do with biasing ARC gear. Check out his site.
Jim McShane enjoys a very good reputation and while I've yet to buy from him, I would if the need arose. He is very good with email replies but is just coming back from an illness so might be a little slow due to back log. You might consider contacting him to see what he has to say.
If you want to follow the safest course, why not buy them from ARC? Supposedly they are extremely rigorous with their tube screening procedures. They will charge a premium over what you can pay elsewhere. Assuming they aren't asking 5 or 10x more and since you only need two tubes, spending the extra $ for the "peace of mind" might be best.
For factory matched new power tubes like KT120s and KT150s I've used reputable (100% ratings with thousands of transactions) Ebay dealers with great success (Upscale lists stuff on Ebay also), and have bought matched signal tubes from "thetubestore" (new and NOS) and Upscale (NOS). Most have been fine, although some Psvanes from Ebay were bad…oops...
I've had excellent experiences with both "tctubes.com" (Tyler and Chelsea are a pleasure to deal with, and they really know their stuff) and Brent Jessee at “audiotubes.com" who is an expert with all kinds of tubes. I bought two matched quads (four years apart) of Genelex Gold Lion KT-77's from tctubes, and have been extremely satisfied. More recently, I bought a set of five "small tubes" from Brent Jessee ..... a matched pair of GE JG 5751 backplate triple mica premium military grade (12AX7 spots), a matched pair RCA 12AU7 Cleartops (12AU7 spots) and a single Telefunken ECC82 smooth plate diamond mark (center 12AU7 spot) ..... for my Rogue Audio Cronus. Fantastic tubes making beautiful music. Life is good !
Hi, anyone familiar with 6N1 and 6P15 tubes? I bought an inexpensive hybrid amp for a small system and would like to try different tubes. Being a tube preamp stage only, I'm not expecting alot of change, but thought I'd ask.
If you're familiar with these tubes I'd appreciate your input. I'm emailing some of the guys already mentioned in the post, fwiw.
Thanks in advance
Just got off the phone with Kalvin at ARC regarding KT120 or 6550. I will do 6550 because transformer will run hotter with KT120 and will shorten life of transformers. So I only need one matched pair of 6550.If you are looking for a set of matched KT-88s, you can get some very decent JJs from https://www.cedist.com/ (formerly Antique Radio Supply) in Arizona. They make distinctly better KT-88s than the usual Russian or Chinese fare.
Andy Bowman is a good source for NOS types. TC Tubes is a good vendor too. We've done very well by Upscale Audio.
Question for Atmasphere: Do you think JJ has resolved quality problems? I had some KT88s from them a while back. They sounded great but did not last. Failed in a damaging way to the JoLida integrated I was running at the time. I'd be pleased to hear they've resolved those issues, though I do note some of the suppliers above (Jim McShane & Kevin Deal) still do not carry any JJ product. Just curious on your read of that situation. Thanks.
Another nod to Andy at Vintage Tube Services. He has an endless knowledge of tubes, tube components and speakers and is always willing to take the time to answer your questions. I recently purchased a matched quad of RCA 6L6GC black plates from him that have transformed the sound of my amp.....he matched them perfectly. Great guy. Great product. Great service.
Great suggestions above, pretty well covering the gamut of reputable sellers. Jim McShane is the best of the best in my view. There are lots of good prices from tube sellers on e-bay, but it is very easy to get burned there. It is hard to separate the wheat from the chaff with some of these sellers.
I can buy anywhere as long as the seller guarantee it's tubes on test results on what tester but not on emission test.Pay attention for matched transconductance and plate current.Double triode like 12A( )7,6sn7,ecc88 etc.,they must be matched at least 10% or tighter triode-triode for Gm & Ip,non-microphonic,very low noise and no hum.
Question for Atmasphere: Do you think JJ has resolved quality problems? I had some KT88s from them a while back. They sounded great but did not last. Failed in a damaging way to the JoLida integrated I was running at the time. I'd be pleased to hear they've resolved those issues, though I do note some of the suppliers above (Jim McShane & Kevin Deal) still do not carry any JJ product. Just curious on your read of that situation. Thanks.We've been using them in guitar amps and they've been holding up really well. As a side note though- a couple of tips:
1) all power tubes should be preconditioned if possible. This would be the process of applying filament current to the tube but no B+ (power). The tube should be lit up in this way for 3 days and nights for best effect. If B+ is applied, the preconditioning process is ended so you have to be patient. This can double the life of the tube and dramatically reduce premature arcing that might simply be the result of damage to the cathode coating in shipment.
2) in many transformer coupled amplifiers that employ a pentode or a tetrode, the cathode resistors and screen resistors are always at risk in the event of a tube failure. IOW this is nothing unique to JJ! I've Genelex and GE and you name it do exactly the same thing- its the result of the tube arcing. To reduce that in a new tube, see 1) above.
@atmasphere Is preconditioning what tube-sellers are usually talking about when they offer 24 hour burn in of power tubes?Generally not.
Ralph,What value of B+?since those tubes you got from the seller, he already applied B+ on them when they were tested.And one more thing about cathode poisoning if you run it for 3 days?If the tube is going to be properly preconditioned, B+ simply should not be applied until after the preconditioning is complete.