Pass DIY Addict
Joined 2000
Paid Member
Some of the NuTube triodes ring very easily from mechanical vibrations transmitted through the chassis and standoffs...
Yep, I've found a ring at about 5200-5300Hz. Using a set of rubber standoffs will reduce the ringing by about 15dB. This reduced my ring to a point where I don't hear it anymore. Others have added better feet and vibration damping to the chassis to good effect as well. Definitely worth a bit of effort to make the mods for such a nice preamp!
Have u build a tube preamp? Spent alot on one single clone and never regretted. It's special.
This is the first tube preamp I have had in my system. But I have heard many others in friend’s systems, etc.
I don’t necessarily think the Korg is objectively better than the SS preamps. But for certain music and genres it does sound glorious.
But it’s missing that solid foundation and precision of the solid state preamps. Sounds more diffuse. It’s a trade off. Precision and truth vs. an enhanced experience.
Iam guessing that Nelson has tried to bring these worlds together with amps like the SIT amps. Curious why he seems to be a proponent of 2nd harmonic dominant sound (or “triode” curves) in his personal work yet his commercial Pass Labs offerings are clearly designed to null harmonics with super symmetry.
Perhaps the balanced outputs on the pass labs stuff have something to do with it.
Curious why he seems to be a proponent of 2nd harmonic dominant sound (or “triode” curves) in his personal work yet his commercial Pass Labs offerings are clearly designed to null harmonics with super symmetry.
.
This is actually no longer quite true, the .8 amps have some asymmetry added.
Apologies if this has already been covered, but when can we expect the diyAudio store to have the B1 Korg PCBs back in stock?
This is the first tube preamp I have had in my system. But I have heard many others in friend’s systems, etc.
I don’t necessarily think the Korg is objectively better than the SS preamps. But for certain music and genres it does sound glorious.
But it’s missing that solid foundation and precision of the solid state preamps. Sounds more diffuse. It’s a trade off. Precision and truth vs. an enhanced experience.
Iam guessing that Nelson has tried to bring these worlds together with amps like the SIT amps. Curious why he seems to be a proponent of 2nd harmonic dominant sound (or “triode” curves) in his personal work yet his commercial Pass Labs offerings are clearly designed to null harmonics with super symmetry.
Perhaps the balanced outputs on the pass labs stuff have something to do with it.
Well.. I also wanted a triode solid state preamp. But vfet is hard to get.. 2sk28. Papa Nelson say sit 1 sound almost similar to el34 single ended triode mode ampli with added bandwidth.. Greedy greedy mode on
Good questions.. I guess it's market demand.? My guess is.. Symmetry provide less need for coupling. Thus More transparent, therefore cheaper to achieve better results for much less.. H3 harmonics on preamp with balanced. matches better with H2 dominant amp which is almost all amplifier and lower thd also equals more informations/detailed
A joke. Aquantance spent 50k on phono stage.. Wow wow.. Right.. But when he got alot cheaper one Ops missed out plenty of detailed.. Curse and swear. After that same with preamp.. He got a old preamp cheap one.. Lost again Curse and swear again.. Rich men... Problem wahaahhahah.. At high lvl... It's all detail. Naturalness and musicality always get confused...listenkng to enjoy or.. .. I wonder. I'll keep my cheapo ears. No thank you. Lolol
Last edited:
Well, to my ears it sounds terrific. Bass is solid and deep, detail and soundstage very nice.
I was having a bit of ringing before I got the glass front on, has been fine since. This thing is rather heavy for its size, and while vented around the top and bottom, the nutube is fairly sheltered. The F6 will get a matching glass front.
Michael
I was having a bit of ringing before I got the glass front on, has been fine since. This thing is rather heavy for its size, and while vented around the top and bottom, the nutube is fairly sheltered. The F6 will get a matching glass front.
Michael
Attachments
Apologies if this has already been covered, but when can we expect the diyAudio store to have the B1 Korg PCBs back in stock?
I have 199 sitting at my feet, shipping tomorrow.
Iam guessing that Nelson has tried to bring these worlds together with
amps like the SIT amps. Curious why he seems to be a proponent of 2nd
harmonic dominant sound (or “triode” curves) in his personal work yet his
commercial Pass Labs offerings are clearly designed to null harmonics with
super symmetry.
My personal work (FW and DIY) are separate from Pass Labs. Pass Labs is
serious about business, and other stuff is largely my playground.
I don't think of myself as a proponent of 2nd harmonic or any form of
distortion. I just think it is interesting to play with.

With 3706 Posts, there is a lot of playing being done, and the discoveries are just coming to the surface 😀
I'll have one to enjoy soon as well.
I'll have one to enjoy soon as well.
I have 199 sitting at my feet, shipping tomorrow.
Thank you Mr. Pass.
I am guessing that it will be a Christmas present of choice (of course to self) for a good number of DIYers. 🙂
Dear Genntlemen,
in order to connect an active DIY subwoofer to the B1 Nutube preamp, I would like to add a specific second RCA output. Like I am still a newbie, I don’t know how to do...
Do you think it is simply possible? If yes, could you show me a possible schematic...
I thank you really much for your support and advices.
Musically yours.
TYM
in order to connect an active DIY subwoofer to the B1 Nutube preamp, I would like to add a specific second RCA output. Like I am still a newbie, I don’t know how to do...
Do you think it is simply possible? If yes, could you show me a possible schematic...
I thank you really much for your support and advices.
Musically yours.
TYM
Hi !
The easiest way is to connect it in parallel with a Y cable (1 RCA male and 2 RCA female) on a single output of the preamp to avoid being in mono on the output of the B1K ...
The low frequencies are usually mixed in mono. But to get it right, it would be necessary to implement a summing circuit at the exit of the B1K.
Gidu
The easiest way is to connect it in parallel with a Y cable (1 RCA male and 2 RCA female) on a single output of the preamp to avoid being in mono on the output of the B1K ...
The low frequencies are usually mixed in mono. But to get it right, it would be necessary to implement a summing circuit at the exit of the B1K.
Gidu
Last edited:
I have a sub plate amps under each main speaker they extract a signal from the speaker cable coming from the main power amps. The design of the plate amp is intended to combine the feed from left and right channels into one mono sub bass output. In my case I use a short length of speaker cable that goes from the binding posts of the sub plate up to the main driver above and a couple of very short jumper cables across the binding posts for good measure. Neither the pre-amp or power amp see anything that could be described as a load. I suspect having a sub for each channel helps integrate the sound with the main drivers but i’ve Never had a single sub set up so can’t advise you on that.
Well, to my ears it sounds terrific. Bass is solid and deep, detail and soundstage very nice.
I was having a bit of ringing before I got the glass front on, has been fine since. This thing is rather heavy for its size, and while vented around the top and bottom, the nutube is fairly sheltered. The F6 will get a matching glass front.
Michael
That’s very cool. Have you created a mask and the sandblasted it or bought window privacy film and cut through it?
I just noticed Pete published a few months ago a balanced
Korg tube line stage:
Nutube Balanced Amp
Does anyone have any experience with it?
Thanks,
Dennis
Korg tube line stage:
Nutube Balanced Amp
Does anyone have any experience with it?
Thanks,
Dennis
I just noticed Pete published a few months ago a balanced
Korg tube line stage:
Nutube Balanced Amp
Does anyone have any experience with it?
Thanks,
Dennis
Looks nicely laid out and is a true balanced circuit not a doubled up one..
I am planning on building it.
nash
I have been using my Pass Korg as a headphone buffer lately (only to be used with high sensitivity headphones) and it gives a Sony ZR1 surpassing liquidity, really tasty.
I think that a new category has been created. Instead of 'directly heated triode' we now have the 'directly flourescing triode'. Pass Korg sounds like a slightly dry directly heated triode (a good thing, not a bad thing).
I think that a new category has been created. Instead of 'directly heated triode' we now have the 'directly flourescing triode'. Pass Korg sounds like a slightly dry directly heated triode (a good thing, not a bad thing).
- Home
- Amplifiers
- Pass Labs
- B1 with Korg Triode