Diode polarity are OK.
Specially capacitors joints need some re-work.
Interesting video with all detailed important parameters
Good luck
Basic Soldering Lesson 1 - "Solder & Flux" - YouTube
Specially capacitors joints need some re-work.
Interesting video with all detailed important parameters
Good luckBasic Soldering Lesson 1 - "Solder & Flux" - YouTube
In the first post pdf Mr. Pass says, “ Remember that the preamp is phase-inverting. In order to get the correct absolute phase coming out of the speaker you must invert the phase after the preamp. The easiest place to do this is at the loudspeaker.”
Does this simply mean to switch the black and red speakers cables on the speaker?
Does this simply mean to switch the black and red speakers cables on the speaker?
Oh, with this little unit there are many interesting psychoacoustic tricks playing pleasantly with our ears...
Just give it a listen and try to find out these... without expecting anything / bias
Enjoy iy
Claude
PS / hint: swapping the LS cables brings you the correct phase AND also moves you from positive to negative H2 in that case
Just give it a listen and try to find out these... without expecting anything / bias
Enjoy iy
Claude
PS / hint: swapping the LS cables brings you the correct phase AND also moves you from positive to negative H2 in that case
Hi, there is also a specific thread about a balanced version of the B1 Nutube. I don't remember his name, but this member did a lot of deep tests and measurements on this particular configuration. Other than this, I used output transformers to get balanced signal from se with good results to my ears.
Gaetano
B1 Completion
I finished my B1 kit a few days ago and had zero problems. I’m very happy, actually ecstatic, about how great it sounds for so little money. I’m using it with my Pass Labs Aleph 3 and it sounds wonderful. I haven’t tried it with my mono
Amp Camp Amps yet but will soon. I lined the top and bottom covers with Dynamat and mounted the NuTube on the little piece of white foam that came with the tube. I encountered no problem with microphonics. I can tap on the chassis at full volume with no source signal and hear nothing. I was very concerned after all I had read about microphonics but I apparently lucked out big time. I’m a little confused over setting the voltage using the trim pots. Can someone state with certainty what the minimum and maximum voltages are? Also, did I understand correctly that the need to swap the phase of the speakers or not depends on this voltage setting? Has anyone noted any sonic changes with break-in of the preamp?
I finished my B1 kit a few days ago and had zero problems. I’m very happy, actually ecstatic, about how great it sounds for so little money. I’m using it with my Pass Labs Aleph 3 and it sounds wonderful. I haven’t tried it with my mono
Amp Camp Amps yet but will soon. I lined the top and bottom covers with Dynamat and mounted the NuTube on the little piece of white foam that came with the tube. I encountered no problem with microphonics. I can tap on the chassis at full volume with no source signal and hear nothing. I was very concerned after all I had read about microphonics but I apparently lucked out big time. I’m a little confused over setting the voltage using the trim pots. Can someone state with certainty what the minimum and maximum voltages are? Also, did I understand correctly that the need to swap the phase of the speakers or not depends on this voltage setting? Has anyone noted any sonic changes with break-in of the preamp?
Hi Frank,
Glad you enjoy your unit, well done... I am still amazed by it
Regarding the voltage setting and the adjustment range, I asked before and as far as I remember you can adjust as you wish, no danger at all. As of the sound, that's of course different... Try between say 9 and 15V to start with IMHO, that's already a wide playfield.
You may need to swap the the phase of the speakers to get the phase right as the B1 Korg is phase inverting per se. That is not related to the voltage setting and some feel the need to get the phase right, others don't hear absolute phase.
Now, there is a thing with the voltage setting and the phase of H2, not exactly the speakers... directly. If you do invert the speaker cables as suggested by Papa and have settings below the "H2 nulling point" (around 12V, please refer to Papa's paper), you do have negative phase H2 as intented. If you don't reverse the speaker cables, you will have wrong polarity and also have positive H2, which is not the initial intention.
There is indeed a way to get wrong polarity and negative H2 without having to invert the cable speakers, but I won't confuse you with that.
Last but not least, small break-in period indeed in my case... gets even better, but its existence might depend on components used
I hope this helps
Claude
Glad you enjoy your unit, well done... I am still amazed by it
Regarding the voltage setting and the adjustment range, I asked before and as far as I remember you can adjust as you wish, no danger at all. As of the sound, that's of course different... Try between say 9 and 15V to start with IMHO, that's already a wide playfield.
You may need to swap the the phase of the speakers to get the phase right as the B1 Korg is phase inverting per se. That is not related to the voltage setting and some feel the need to get the phase right, others don't hear absolute phase.
Now, there is a thing with the voltage setting and the phase of H2, not exactly the speakers... directly. If you do invert the speaker cables as suggested by Papa and have settings below the "H2 nulling point" (around 12V, please refer to Papa's paper), you do have negative phase H2 as intented. If you don't reverse the speaker cables, you will have wrong polarity and also have positive H2, which is not the initial intention.
There is indeed a way to get wrong polarity and negative H2 without having to invert the cable speakers, but I won't confuse you with that.
Last but not least, small break-in period indeed in my case... gets even better, but its existence might depend on components used
I hope this helps
Claude
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Thanks, I read Mr Pass's thread at 1890 and going balance will lose a bit of the 2nd harmonic distortion which is probably not beneficial. I'm thinking to just leave it single ended and use the earlier Balanced Line Stage aka Bride SOZ preamp instead.
The NuTube will just have to be paired with my existing SE tube amps.
Hello everyone, the B1K is vertig, which made me very happy, although a bit disappointed. Compared to its predecessor B1, the B1K has lost some of its clarity in my case, sounds a bit muffled, but sounds more elegant and lively. I combine this lower resolution with B1K with the use of electrolytic capacitors, and plan to replace them at some point. In B1 I had built in Supreme Silver Oil from Mundorf, which are great in themselves, even not comparable with WIMA10. Maybe that's why I'm a little disappointed.
to dezibaby
Hello dezibaby,
I have another experience with the B1 NUTUBE-preamp compared too the B1- buffer.
In my opinon it strongly depends on how you adjust your B1 NUTUBE (positive / negative 2nd harmonic) over the 10kohm pots.
In most cases my B1 NUTUBE-pre sounds better, if the polarity at poweramp is inverted (you know that B1 NUTUBE is inverting phase).
The B1 is only a buffer without gain. Less parts...Only one JFet as active device per channel. The B1 NUTUBE -pre shall have a 'tuby' sound.
For sure you can try better caps. I also like the Mundorfs.
Ever tried the Nichicon MUSE UES bipolars (greensleeves). In my opinion
they sound great - especially at this reasonable price. But you can always find
better - and more expensive - caps.....
You know that the cap discussion is endless... Try it.
Greets
Dirk
Hello dezibaby,
I have another experience with the B1 NUTUBE-preamp compared too the B1- buffer.
In my opinon it strongly depends on how you adjust your B1 NUTUBE (positive / negative 2nd harmonic) over the 10kohm pots.
In most cases my B1 NUTUBE-pre sounds better, if the polarity at poweramp is inverted (you know that B1 NUTUBE is inverting phase).
The B1 is only a buffer without gain. Less parts...Only one JFet as active device per channel. The B1 NUTUBE -pre shall have a 'tuby' sound.
For sure you can try better caps. I also like the Mundorfs
.Ever tried the Nichicon MUSE UES bipolars (greensleeves). In my opinion
they sound great - especially at this reasonable price. But you can always find
better - and more expensive - caps.....
You know that the cap discussion is endless... Try it.
Greets
Dirk
Hi,
Yep, change the electrolytics for PPP caps, that made a big difference to me.
And as per above, if you like it less sirupy, don't hesitate to play with the voltage adjustment. I like it far less biased than the recommended starting point, that makes also a big difference IMHO.
It is a unit that sounds great out of the box but one that allows so many things to play with ... to make it YOUR dream machine.
Claude
Yep, change the electrolytics for PPP caps, that made a big difference to me.
And as per above, if you like it less sirupy, don't hesitate to play with the voltage adjustment. I like it far less biased than the recommended starting point, that makes also a big difference IMHO.
It is a unit that sounds great out of the box but one that allows so many things to play with ... to make it YOUR dream machine.
Claude
And the fun continues...
I finally had a chance to turn the volume up above the first quarter and ... ouch!
Loads of run away bass from the right channel. It seems that I had 'blown' the capacitor that I had accidently reversed on first assembly. Thankfully I had a pair of Silmic II caps of the same rating and in they went. Problem solved.
I currently have a head cold and blocked ears which is preventing any serious listening but what I'm hearing so far is really interesting. I'm very used to the lean sound of my chrome bumper Naim 32.5 preamp. The B1Korg produces a lot more extension and information in the bass ranges by comparison. Once the ears are cleared, it looks like I'm going to playing with speaker positioning for a while.
This is through a single ACA, The F5 is currently sitting in front of me while I figure out the cable routing. I'm hoping this will exercise more control over my speakers once it's finished. Has anybody else used this combination?
I finally had a chance to turn the volume up above the first quarter and ... ouch!
Loads of run away bass from the right channel. It seems that I had 'blown' the capacitor that I had accidently reversed on first assembly. Thankfully I had a pair of Silmic II caps of the same rating and in they went. Problem solved.
I currently have a head cold and blocked ears which is preventing any serious listening but what I'm hearing so far is really interesting. I'm very used to the lean sound of my chrome bumper Naim 32.5 preamp. The B1Korg produces a lot more extension and information in the bass ranges by comparison. Once the ears are cleared, it looks like I'm going to playing with speaker positioning for a while.
This is through a single ACA, The F5 is currently sitting in front of me while I figure out the cable routing. I'm hoping this will exercise more control over my speakers once it's finished. Has anybody else used this combination?
HI All,
Have just completed my build of the B1 Nutube, and has measured in T7 and T8. No Smoke yet However, T5 and T6 measure 0,67V, i.e. plate voltage is a little up. Is this a issue ? I assumed it to be within the acceptable range, but it would be good to get a little input.
Mikael
Have just completed my build of the B1 Nutube, and has measured in T7 and T8. No Smoke yet
However, T5 and T6 measure 0,67V, i.e. plate voltage is a little up. Is this a issue ? I assumed it to be within the acceptable range, but it would be good to get a little input. Mikael
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