To be absolutely sure, I double checked all the actual numbers from the book by Kaneda, P.15.
The difference to the schematics of the first link of post #4 is the second stage LTP bias resistor, which is 3.6k instead of 4.3k.
The rest are identical.
The output stage bias in the book is listed as 7.6 mA.
But this depends also on the Idss of the 2SJ103BL pair.
Hence the inclusion of R5a,b on the PCB, which allows the bias to be adjusted without changing the gain structure of the circuit.
Patrick
The difference to the schematics of the first link of post #4 is the second stage LTP bias resistor, which is 3.6k instead of 4.3k.
The rest are identical.
The output stage bias in the book is listed as 7.6 mA.
But this depends also on the Idss of the 2SJ103BL pair.
Hence the inclusion of R5a,b on the PCB, which allows the bias to be adjusted without changing the gain structure of the circuit.
Patrick
This lovely preamp is currently sitting in my system here, with a planned audition with some friends tomorrow.
I thought some internal pictures might be of interest.
As outlined earlier in the thread, there are independent power supplies for each channel, and then a third PSU board provides for the source select and attenuator. All signal paths are kept as short as possible, and as far away as is practical from the AC side of power supplies. Control cables for attenuation and source select run from the front panel to the respective boards towards the rear of the amp which also helps with keeping cable runs short.
I thought some internal pictures might be of interest.
As outlined earlier in the thread, there are independent power supplies for each channel, and then a third PSU board provides for the source select and attenuator. All signal paths are kept as short as possible, and as far away as is practical from the AC side of power supplies. Control cables for attenuation and source select run from the front panel to the respective boards towards the rear of the amp which also helps with keeping cable runs short.
Attachments
Actually the basic layout is the same as the F5 Preamp :
www.diyaudio.com/community/threads/the-f5-preamp-2024.419289/
And very similar to our Preamp for Le Monstre :
www.diyaudio.com/community/threads/preamp-for-hiraga-le-monstr-2024.421562/
The difference is that while the F5 Preamp uses a custom-designed Chasing-LED indicator for volume settings, the Kaneda 168 has a much simpler 3-digit 7-segment LED display.
This is made much easier for people without access to milling machines by the BZ3207 case.
We only need to design PCBs to match the front panel.
And both of them use the W-ONE attenuator.
The Preamp for Le Monstre also uses a Chasing-LED, but this time totally without MCU.
It used our own version of ADC0804 to control a 8-bit ladder.
If you only need a buffer and no voltage gain, the buffer circuits used in the LM Pre is a better choice than the K168.
www.diyaudio.com/community/threads/a-trio-of-4-transistor-line-buffers.427057/
K168 is like a discrete opamp. It is very versatile.
On the drawing board, there is a K168 in DIP8 footprint for normal line level loads.
Will take a few months.
😊
Patrick
www.diyaudio.com/community/threads/the-f5-preamp-2024.419289/
And very similar to our Preamp for Le Monstre :
www.diyaudio.com/community/threads/preamp-for-hiraga-le-monstr-2024.421562/
The difference is that while the F5 Preamp uses a custom-designed Chasing-LED indicator for volume settings, the Kaneda 168 has a much simpler 3-digit 7-segment LED display.
This is made much easier for people without access to milling machines by the BZ3207 case.
We only need to design PCBs to match the front panel.
And both of them use the W-ONE attenuator.
The Preamp for Le Monstre also uses a Chasing-LED, but this time totally without MCU.
It used our own version of ADC0804 to control a 8-bit ladder.
If you only need a buffer and no voltage gain, the buffer circuits used in the LM Pre is a better choice than the K168.
www.diyaudio.com/community/threads/a-trio-of-4-transistor-line-buffers.427057/
K168 is like a discrete opamp. It is very versatile.
On the drawing board, there is a K168 in DIP8 footprint for normal line level loads.
Will take a few months.
😊
Patrick
if you don't mind e-versions (on viewer), it is very simple buying MJ form fujisan.co.jp
Edit: I just realized hat the ISBN corresponds to one of the design compilations. Still, Fujisan might be helpful if looking for newer Kaneda designs.
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Fran and 4 others have completed the ABX auditioning of the K168 / GoFiSS combo vs a J2 clone driven also by the K168.
ABX test was done using the purpose built power amp switch box we made for the Le Monstre 2024.
www.diyaudio.com/community/threads/hiraga-le-monstre-2024.413301/post-7695899
He said he would write up properly and post at the GoFiSS thread when he has time.
(I already know the results.) 😊
But I asked him to also benchmark the K168 against another preamp well known here.
We did the same against his iron pre for the F5 Preamp.
www.diyaudio.com/community/threads/the-f5-preamp-2024.419289/post-7948969
So he plans to do the same here, probably this weekend.
Busy with work during the week.
Patrick
ABX test was done using the purpose built power amp switch box we made for the Le Monstre 2024.
www.diyaudio.com/community/threads/hiraga-le-monstre-2024.413301/post-7695899
He said he would write up properly and post at the GoFiSS thread when he has time.
(I already know the results.) 😊
But I asked him to also benchmark the K168 against another preamp well known here.
We did the same against his iron pre for the F5 Preamp.
www.diyaudio.com/community/threads/the-f5-preamp-2024.419289/post-7948969
So he plans to do the same here, probably this weekend.
Busy with work during the week.
Patrick