B1 with Korg Triode

Hi,
I just ordered a board and a tube. A thought of building an amp designed by Mr. Nelson is just so unreal to me. I am so appreciative of his generosity.
Please allow me to ask 3 questions to begin with.

1. Ordering parts from "D-key", I 've noticed that the Nichicon KAs (1000uf) are in back order. I am thinking of going with the FG series. But I wanted to learn from your experience and wisdom before I order them. What series of caps would be appropriate here, Silmic or etc?

2. Please share your thought about the PSU. The Triad option seems easy and simple. But should there be a better option I would love to learn.

3. This question may not belong here. But has anyone built F5 or F6 amps? I am wondering which amp would match better with the B1.

Thank you!

The 1000ufd are power supply caps and not in the signal chain so any good cap will do the job. The SMPS is regulated at 24VDC so 25V caps are fine, as per Papa's spec. I went a bit higher end with Kemets rated at 10,000 hours and 105deg C
EST108M025AL3EA KEMET | Capacitors | DigiKey

I prefer the Mean Well power supply, mostly for cosmetic reasons. I like the round power cord and the LED pilot light. It just looks like a high end piece. The inline filter choke on the cord is a bonus for reducing hash on the line.
https://www.digikey.com/products/en?keywords=GST25U24-P1J

I've A-B'd the Triad and the Mean Well and cannot hear a difference on the B1K. Other folks have used DIY built supplies. Search this forum for options, many of which cost as much or more than a loaded B1K board.

I have built the F6 as well as the M2X. I personally prefer the F6 with the B1K. Again, you could search this forum for opinions on the F5.
 
GLOL AnthonyA... well I gave up on that motto re cars and women ages ago :)

Soundhappy,
Thanks for sharing that... I had indeed skipped Papa played with LDR... what was his view on that re volume control? Seen the long thread but time is scarse / I am leazy :)
Alps Blue robs a lot of details and soundstage, pretty average indeed, but not all Alps are like that. The Black Beauty I have since 1996 in my system still works perfectly and was defo a big improvement and bettered quite a few $$$ stepped attenuators back then, hard to beat for the money but also regardless the money... The Tocos is today probably in the same league, but I can't go back in time and compare units with a few decades use difference so I will never know.

Thanks again to all -who knows, perhaps I should then look again into LDR one day, when I will have time...

Claude
 
1. Ordering parts from "D-key", I 've noticed that the Nichicon KAs (1000uf) are in back order. I am thinking of going with the FG series. But I wanted to learn from your experience and wisdom before I order them. What series of caps would be appropriate here, Silmic or etc?

Note: The FG series are a larger diameter (16mm vs 10mm) and have a wider lead spacing (7.5mm vs 5mm) so you may have trouble getting them to fit on the PCB. The Elna Silmics are also too large and match the FG size.

original spec from the parts list is KW series:
https://www.digikey.com/products/en?keywords=493-15476-ND

There are other offerings from Nichicon, Panasonic and Kemet in that size/form factor.

In my previous post I mentioned some extended life/high temp Kemets I used that were 13mm OD. They were a bit tight on the PCB. And maybe not ideal (read on):

After reading this month's Audio Express article this afternoon on power supply caps, I discovered that the 105deg C caps typically have higher ESR which translates into more resistive noise. So I will be dropping back to the 85deg C caps in the future.
 
..Soundhappy, looks like your treasured B1 Korg will be kept in... a safe :))

Haha Vishay/Spectrol have 10 tours but vernier dial do the trick and "translate" them to 1 tour
just like classic ordinary volume potentimeter and position is show by the numbers from 1 to 10
with milimetric precision for great stereo :note:
 

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Soundhappy,
Thanks for sharing that... I had indeed skipped Papa played with LDR... what was his view on that re volume control?

Many passive volume controls ( simple pot etc. ) are build without jfet buffer so if audio source ( DAC , tourntable, CD player )
output impedance don't match well power amplifier input impedance then music frequency bandwith response is reducted
( less highs and bottom end ) LDR , AVC , TVC work much better with impedance buffer.
Happy B1K have this at the input/output :) Best regards
 
Hi Thanks so much for the reply. A few more questions please. Following your posts I've noticed that you've built 6 of B1s. And I also noticed that you've used different caps (blue, orange but could not see the brand).

There are other offerings from Nichicon, Panasonic and Kemet in that size/form factor.

1. I might stick with Nichicon KW or Pana FM, FC, or FR. Your suggestion?
2. Are you using the Triad as Mr. Nelson suggested or have you experiment with PSU?
3. It looks like Mr. Nelson is open to go higher than 1000uf ... to 2200uf. Have you tried this?

This is not a question but I've found it facinating that you've matched the B1 with F6 for high/mid. Does that mean you are biamping with a different amp for your bass? Wow!

I am actually looking to build one of Mr. Nelson's power amp. I am definitely looking into F6 as a strong option after reading your posts.

After reading this month's Audio Express article this afternoon on power supply caps, I discovered that the 105deg C caps typically have higher ESR which translates into more resistive noise. So I will be dropping back to the 85deg C caps in the future.
I learned something new today. And I will stick with the 85deg caps.

Thank you!
 
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1. I might stick with Nichicon KW or Pana FM, FC, or FR. Your suggestion?
2. Are you using the Triad as Mr. Nelson suggested or have you experiment with PSU?
3. It looks like Mr. Nelson is open to go higher than 1000uf ... to 2200uf. Have you tried this?

1. I would stick with the Nichicon UKW caps as originally specified

2. I am using the Mean Well supply

3. I have stayed with 1000uF
 
GLOL AnthonyA... well I gave up on that motto re cars and women ages ago :)

Soundhappy,
Thanks for sharing that... I had indeed skipped Papa played with LDR... what was his view on that re volume control? Seen the long thread but time is scarse / I am leazy :)
Alps Blue robs a lot of details and soundstage, pretty average indeed, but not all Alps are like that. The Black Beauty I have since 1996 in my system still works perfectly and was defo a big improvement and bettered quite a few $$$ stepped attenuators back then, hard to beat for the money but also regardless the money... The Tocos is today probably in the same league, but I can't go back in time and compare units with a few decades use difference so I will never know.

Thanks again to all -who knows, perhaps I should then look again into LDR one day, when I will have time...

Claude
OK. I know you lived your life to the fullest already
 
Quote; OK. I know you lived your life to the fullest already

Hi Anthony,
Well, to be completely honest with you, I had and still have indeed a very pleasant life, but regarding 'life to the fullest' I learned more humbly my very own limitations LOL!
And perhaps I am more conservative than adventurous nowadays :)

Having said that, I wish we can all get back to normal life soon as I really miss the soldering iron... and the race circuits. Luckily I have spouse and son with me, so at least very lucky not to be confined alone...

Stay safe and thanks for your humourous note in a cold world

Claude
 
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Quote; OK. I know you lived your life to the fullest already

Hi Anthony,
Well, to be completely honest with you, I had and still have indeed a very pleasant life, but regarding 'life to the fullest' I learned more humbly my very own limitations LOL!
And perhaps I am more conservative than adventurous nowadays :)

Having said that, I wish we can all get back to normal life soon as I really miss the soldering iron... and the race circuits. Luckily I have spouse and son with me, so at least very lucky not to be confined alone...

Stay safe and thanks for your humourous note in a cold world

Claude

Very unfortunate on our side. To be confined 24x7 with them.