Part 2 on active devices, as promised.
Here a new pdf to combine both Part 1 & 2.
Enjoy,
Patrick
.
Here a new pdf to combine both Part 1 & 2.
Enjoy,
Patrick
.
Patrick, thanks for sharing. Just like the input devices, make some allowance of alternative output devices, including the Toshiba 2013/313 pair. Thanks.
Patrick,
Renesas 2SJ 76/77/78/79 and 2SK 213/214/215/216 are announced EOL
do you have any idea where there might be some genuine ones still ?
Fakes abound as usual.
Renesas 2SJ 76/77/78/79 and 2SK 213/214/215/216 are announced EOL
do you have any idea where there might be some genuine ones still ?
Fakes abound as usual.
If the plan is to offer both matched input and output FETs to case/project subscribers, I have a feeling that Patrick has already secured a nice stash of 2SK214/2SJ77's. 🙂
Yes, we have enough genuine, tested devices to support at least 2 batches of this project, if not more. 🙂
They were unfortunately not too cheap. Purchase price was already ~4€ apiece.
We have very limited 2SK2013/2SJ313, and they are not pin compatible.
So it will need a new PCB and can only be supported as a limited option for those who desperately want to experiment.
Unless Mr. Zhou answers his email, whenever .....
We are also searching for other devices which are better complementaries than the above two.
But this will take time. So even if successful, it will come a year later as potential upgrades.
Default will be Renesas laterals.
Patrick
They were unfortunately not too cheap. Purchase price was already ~4€ apiece.
We have very limited 2SK2013/2SJ313, and they are not pin compatible.
So it will need a new PCB and can only be supported as a limited option for those who desperately want to experiment.
Unless Mr. Zhou answers his email, whenever .....
We are also searching for other devices which are better complementaries than the above two.
But this will take time. So even if successful, it will come a year later as potential upgrades.
Default will be Renesas laterals.
Patrick
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Thank you Patrick,
my first christmas present this year!
One remark concerning the attenuator. -48dB seems not to be very much. I´ve got a bit over -60dB at the moment (from a X-BOSOZ with Gain 3.9x) and in some combinations (Zu Druid, NCore400) this is only just enough.
cheers,
William
my first christmas present this year!
One remark concerning the attenuator. -48dB seems not to be very much. I´ve got a bit over -60dB at the moment (from a X-BOSOZ with Gain 3.9x) and in some combinations (Zu Druid, NCore400) this is only just enough.
cheers,
William
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Re attenuation :
You can always change the values by dividing the shunt resistor further by 2, or 4, or ....
You total range remains the same, limited by the 8 bit relays.
Or you can step them by a factor of 3, like 30k, 10k, 3,3k, 1k, 330R, 100R, 33R, 11R.
Then you will get -65dB.
Will need a different look-up table, but not impossible.
Patrick
You can always change the values by dividing the shunt resistor further by 2, or 4, or ....
You total range remains the same, limited by the 8 bit relays.
Or you can step them by a factor of 3, like 30k, 10k, 3,3k, 1k, 330R, 100R, 33R, 11R.
Then you will get -65dB.
Will need a different look-up table, but not impossible.
Patrick
We won't make the source code public.
But we can manage to support two versions I think.
Patrick
But we can manage to support two versions I think.
Patrick
Thanks Patrick. Looking forward to the next (last?) installment on the preamp. This unit should perfectly fit the needs of my system.
Have a great holiday!
Have a great holiday!
Knowing how you love SMDs, I was almost certain we'd see MELFs on the attenuator! 😛
Merry Christmas Patrick and Xen gang!
Merry Christmas Patrick and Xen gang!
Bravo Patrick.............best project in a while.
How about a conceptual schematic (block diagram/flow chart). Definitely a must build.
Thanks and Merry Christmas...................
Regards,
Jam
How about a conceptual schematic (block diagram/flow chart). Definitely a must build.
Thanks and Merry Christmas...................
Regards,
Jam
Patrick
Is it possible to run two preamp boards in your case, as I am using J Rivers MC18 as my sole source and crossover (as i cant find a suitable balanced crossover to place after the preamp) outputting two signals, Hf,LF, over USB into a exaU2I Multichannel Asynchronous USB to I2S Interface, into two dacs, into two? preamps, feeding two of your FX5's. Or can anyone suggest a better way of going active balanced ?
Tony
Is it possible to run two preamp boards in your case, as I am using J Rivers MC18 as my sole source and crossover (as i cant find a suitable balanced crossover to place after the preamp) outputting two signals, Hf,LF, over USB into a exaU2I Multichannel Asynchronous USB to I2S Interface, into two dacs, into two? preamps, feeding two of your FX5's. Or can anyone suggest a better way of going active balanced ?
Tony
A friend is using F5XP & F5X for active crossover for his 2-way bookshelf.
He is going to use the F5XP to drive a purely passive filter network (LF & HF parallel).
These networks are followed by JFET follower, which then drives the F5XP.
I consider this a good solution indeed.
Patrick
He is going to use the F5XP to drive a purely passive filter network (LF & HF parallel).
These networks are followed by JFET follower, which then drives the F5XP.
I consider this a good solution indeed.
Patrick
Thanks for the idea, LF & HF Parallel to obtain the balanced output? Any further details would be of great help.
Tony
Tony
No.
LF & HF in parallel so that you have one preamp driving two filters giving you 2 outputs.
That is per channel, so 4 outputs altogether for 2 channels 2-way active filter.
To use a passive filter followed by source followers, just treat them as single ended and duplicated 2x for balanced.
Suggest you start a new thread and also let other people help you.
Or you send me your X'ovr schematics by email and I'll have a look, when I have time ....
Patrick
LF & HF in parallel so that you have one preamp driving two filters giving you 2 outputs.
That is per channel, so 4 outputs altogether for 2 channels 2-way active filter.
To use a passive filter followed by source followers, just treat them as single ended and duplicated 2x for balanced.
Suggest you start a new thread and also let other people help you.
Or you send me your X'ovr schematics by email and I'll have a look, when I have time ....
Patrick