Hi,
I went across this page from Vanderveen
UL40-S2-Mod
Has anybody tried to build such an amp with 6550 ?
I built a few amps in another life, when I was younger... and now I have a bit more time and money, I'd like to get back to tube amps.
I'm in the period of chossing the design of the amp.
I'm thinking about KT88 PP David Hafler like, but found this pr20he design so simple that it could do the job.
Any advice ?
Regards,
Cedric
I went across this page from Vanderveen
UL40-S2-Mod
Has anybody tried to build such an amp with 6550 ?
I built a few amps in another life, when I was younger... and now I have a bit more time and money, I'd like to get back to tube amps.
I'm in the period of chossing the design of the amp.
I'm thinking about KT88 PP David Hafler like, but found this pr20he design so simple that it could do the job.
Any advice ?
Regards,
Cedric
That is an interesting amp, particularily the way the cathodes are wired up.
I'm no tube guru, but the ECC81 LTP front end is possibly going to need some drive to get the thing to full power (the article says 2V but...) It is similar to the 1st stage of "El Cheapo", which has much easier to drive EL84/6V6/6AQ5. LIKE EL CHEAPO IT COULD LIKELY BENEFIT FROM A CCS ON THE TAIL.
Menno knows his stuff so i'm possibly out to lunch on that. I had the priviledge of meeting Menno, and sat in on a conversation between him and another transformer guru his equal. Most of it was over my head, but it was a heady experience.
Aesthetics are quite nice.
I'm no tube guru, but the ECC81 LTP front end is possibly going to need some drive to get the thing to full power (the article says 2V but...) It is similar to the 1st stage of "El Cheapo", which has much easier to drive EL84/6V6/6AQ5. LIKE EL CHEAPO IT COULD LIKELY BENEFIT FROM A CCS ON THE TAIL.
Menno knows his stuff so i'm possibly out to lunch on that. I had the priviledge of meeting Menno, and sat in on a conversation between him and another transformer guru his equal. Most of it was over my head, but it was a heady experience.
Aesthetics are quite nice.
Thx Planet10.
Menno surely knows his stuff, and his project is of great interest.
Every amp can be tricked to get as close as the sound you like.
About your meeting I know what you're talking about. A friend of my father was working for Jadis and tried to teach me tubes....
Well too far in space for my little teenager head. I learned the hard way by myself, let it go for a good 15 years and now I'm trying to re understand tubes 😀
Menno surely knows his stuff, and his project is of great interest.
Every amp can be tricked to get as close as the sound you like.
About your meeting I know what you're talking about. A friend of my father was working for Jadis and tried to teach me tubes....
Well too far in space for my little teenager head. I learned the hard way by myself, let it go for a good 15 years and now I'm trying to re understand tubes 😀
If one were to build this amp what kind of power trans would you need for a stereo version? That is, how much current and voltage would the power trans be able to supply? regards, 808
Jaz,
Different amp. My review was of the VDV70/100 Amp.
The OP here is talking about the later UL40-S2 Amp or the even later PRH20HE-S2 (according to the thred header) which I think uses an EI core output tranny designed by Menno. I haven't built either of these laater designs.
Bit confused about which he is actually talking about.
Am going to build one of his "Super Triode" designs sometime (Ultralinear + cathode feedback). I have VDV-2100-CFB/H Outpurt Trannies and matching Torroidal Power Tannies on the shelf for a pair of monoblocks. Finding it hard to get enthused for a new build when I am so happy with my 6V6, 6SL7 Baby Hueys.
Cheers,
Ian (Gingertube)
Different amp. My review was of the VDV70/100 Amp.
The OP here is talking about the later UL40-S2 Amp or the even later PRH20HE-S2 (according to the thred header) which I think uses an EI core output tranny designed by Menno. I haven't built either of these laater designs.
Bit confused about which he is actually talking about.
Am going to build one of his "Super Triode" designs sometime (Ultralinear + cathode feedback). I have VDV-2100-CFB/H Outpurt Trannies and matching Torroidal Power Tannies on the shelf for a pair of monoblocks. Finding it hard to get enthused for a new build when I am so happy with my 6V6, 6SL7 Baby Hueys.
Cheers,
Ian (Gingertube)
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The thread was started in december 2009. I brought it back to life because CeDe asked about the PR20HE and I would like to hear experiences with that specific amp.
Visited Menno yesterday. Turned out he lived nearby at about half hour drive. We compared my amp to the PR20HE. Long story short: I'm going to build this amp in the future!
I habe build his ul-40 in stereo and mono. With very high quality components. when they work, absolutely stunning.
My impression though...they are picky on the output tubes, i could really only usw el34 sec...others would give you noise. Just reading gingers comment about oscillations between output tubes and the toroids make me think...even though I do have a 1k grid stopper in place.
It would be interesting to compare the PR20HE with the ul-40...
My impression though...they are picky on the output tubes, i could really only usw el34 sec...others would give you noise. Just reading gingers comment about oscillations between output tubes and the toroids make me think...even though I do have a 1k grid stopper in place.
It would be interesting to compare the PR20HE with the ul-40...
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