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Tube / Valve recommendations

mudchute

Member
2012-01-29 12:23 pm
Forgive me if there's a thread particular to Tubelab users detailing this already, I searched but didn't find one.

There's a vast array tubes and manufacturers available and I was wondering if anyone would like to share their listening experience on tube choices for the Tubelab amp they're being used in and any modifcations done to optimise the amp function for that tube.

I hate to think their might be a clear winning combination that I'm missing out on!
 
You didn't specify which flavor of Tubelab board you're using, which may account for the lack of replies.

Anyhow, in my Tubelab SE I'm using Raytheon 5842s as drivers and TJ 45/n ("mesh" plates, ST bottles) for output. Prior to the TJs I was using various vintage 45s. The TJs blow the vintage stuff away. I'd love to hear the EML solid plates, but they're a bit (ok, a lot) out of my price range right now.

HTH,
Joe
 
more for the tubelab SE

I have tried the 45, 2a3 and 300b tubes in mine. I used the dual voltage edcore power transformer, put in the heater voltage switch that george told us not to, and used 3500 ohm output transformers. I also have a B+ switch and panel meters so I can easily bias different tubes. I find that the 45s have a lot of treble, which I normally don't like, but they are so incredibly detailed, it doesn't bother me. Overall the 45s sound pretty amaizing but you are pretty limited on output. I don't need my music to be very loud, but I tend to like less effiecent speakers. (Von Schweikert VR2s and Dynaco A35 are my two current favorates) and the 45 does not quite cut it. Of the 45s I have half a dozen or so, I have a pair of Tung Sols that I like best, A lone rathion sounds good too. Yes, I realise that I have the wrong output transformers for this, I knew going in that it was probably not going to be enough power.

The 2a3 has less treble, and I like that in this amp. I have a few vintage ones and a pair of the Shugang early 2 plate tubes. I like the sound, they still sound detailed, but more smooth. For me, the 4 watts or so is enough for me 99% of the time. If I am having a party I will push that amp out of the way and get out the push-pull kt88 amp. I know this is not true for everyone though. An issue with the 2a3 on this amp, though is the filement current. The vintage tubes seem to need about 6 amps and the new ones about 8 (I am told, I never actually measured). I now have a 10 amp fliment transformer on mine, but I am having issues with the voltage regulator, it is only rated for 5 amps, I think.

George reccomended the Shugang 300b, but I did not like it as much as he did. I guess I am more sensitive to the extra treble, or my speaker are, or my room, or I listen to too much pop music where the equilize in extra treble for reasons I do not understand. There are many variables. Anyway, I find the Shugang 300b to have the extra treble of the 45 but not as detaled, it sounds more like glare to me, for lack of a better word. I later bought a pair of the Shugang carbon plate tubes, this toned down the treble and sounds more like a 2a3. I really like them, and have had no trouble with the heater curcuit. The Shugang carbon plate is not much more than the regular 300b, but a lot harder to find. All 300b tubes seem to have suffencent power for me, but I still would use a different amp for parties.

If I had it to do over, I would not have included the extra switches and panel meters, it made the build more complicated and I had more things to troublshoot. So I would probably just set it up for 300b and get the carbon plate tubes. Overall this amp sounds fantastic, without a doubt the best I have, probably the best I have heard!

My 2 cents, hope it helps.
 

mudchute

Member
2012-01-29 12:23 pm
For any board really. From what I've read the Tubelab amps (like any amp) seem to respond favourably to certain tubes, I thought it could be a good idea to compile that for everyone to benfit from and, steer their purchases towards know good tubes.

I'm currently in love with my Tung Sol 6L6GC-STR which seem to have the best of all frequencies with no compromises. They turn my Frugel horns into house shakers. Thats with Edcor CXE 25-5-8 OPT's, Edcor choke and PT and an otherwise standard Simple se board (inc the 560ohm cathode resistors). Once I have a few more pennies to sepdn I want to try the Tung Sol 6550 reissue tube which I've read favourable things about.

I did try some Svetlana KT88's but, big bass, average everything else.
 
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OK, you are talking in terms of various octal tubes so you must be asking SSE owners. I don't know of any TSE owners other than George and myself that use octals there. Search around this subforum and you will find lots of write-ups on the SSE (aka Simple SE) and tube types. It's all very subjective and depends on OPTs, speakers, your room, etc.

I like to mix things up, so I don't know if a I have an overall favorite. The EH and SED KT-88s produce awesome bass. SED EL-34s seem to have the most detail with less bass. 6L6 types seem to vary by manufacturer, but lie somewhere in between. I have some JJ 6L6GCs in there right now. I ran Tung Sol reissue 6550s until one of them shorted and blew up the amp. They sounded like the EH KT-88 as far as I could tell. The SED 6550s are a different animal. I also have EH KT-90s, which are an odd bird, especially in triode mode.
 
SSE: I've gone from EH 6CA7, good to SED 6550s, better and now I'm using Gold Lion KT-88s that are dramatically fine-sounding. Imaging, tone, dynamics; they're amazing. Worth the big bucks.

They also stink! Apparently, the fancy paint job paint smells as the tube heats and after about 100 hours, it's just starting to dissipate.

Shouldn't neglect driver tubes, tho'. The differences are smaller than with some other amps like my parafeed 45, but, I've settled on GE 5 Star 6201s with Telefunken 12AT7 a close second and JJs fading, now at least 20 lengths back, at the finish.

While I'm at the opinionated thing I will mention that I pulled the 3, 20uF parallel Aerovox motor runs from the PSU and installed in it's place a 50uF Aerovox and a parallel 47uF Film. Better control of the inexpensive, bungee cord bass driver (Eminence Alpha 10) in one of my speaker systems and maybe did some other good things.
 
For my SSE I started with the JJ EL34s and It isn't really the sound for me. The Tung-Sol 6550s reissue are generally the go to tube for me, they seem to handle most types of music well. I mostly listen to 50's/60's Jazz and they are great for that, and they can handle the classic rock too. I've tried some chinese 6l6gc the sound is good but they break up when you turn it up. I have some Valve art 350Bs and I really like them on Female Vocals.

I also agree about the preamp tube. I started with the jj 12at7, and it wore out. I picked up som NOS RCA 6201's and it was a marked improvement. This weekend I came across an older Mullard (made in Great Britain) 12AT7 and I think I like this one even better.
 

mudchute

Member
2012-01-29 12:23 pm
I have some Valve art 350Bs and I really like them on Female Vocals.

I've been following those with interest. Could I ask what changes, if any you've had to make to your amp to run them?

I've now used a NOS Telefunken diamond bottom 12at7 and a NOS Mullard 12at7 in my SSE. Not much difference between them both, the Mullard is slightly smoother but the Tele' has a wee be more detail to it. Both are great though, I couldn't choose between the two. I also tried the CV4024 military issue 12at7 Mullard but it wasn't very nice. Quite muffled, lacking detail although they're supposedly built very strongly so maybe there's some breaking in to be done, doubtful though.

I've also run some reissue Mullard el34's through the amp too. They're quite similar to the Tung Sol 6L6GC-str tubes (which are my current favourite) but aren't quite as easy on the ear, similar but a close second behind the TS's.

I've read a lot about Electro Harmonix's KT88's so I have some of those on the way now for a listen.
 
I've employed the switch rknize has posted about. It's switches between 6 different bias resistors. And I roll 3 different rectifiers. jj 5ar4/gz34. an old RCA 5u4gb and an old RCA 5y3gt. Between the bias selector and the different rectifiers I can pretty easily adjust to the proper current. for the 350b on my SSE the 5y3 with 430 ohm cathode bias resistor works well.