9v at that point on the schematic.
I'm just giving the guy a warning that his results may vary - I can do (and did) the math too, but something didn't go to plan and I wasted an LED.
You gave good, valid, general information, but haven't looked at the schematic or built this circuit. I'm relaying my experience of this exact unit, that's all. I'm not professing that trial and error is the best method.
I'm just giving the guy a warning that his results may vary - I can do (and did) the math too, but something didn't go to plan and I wasted an LED.
You gave good, valid, general information, but haven't looked at the schematic or built this circuit. I'm relaying my experience of this exact unit, that's all. I'm not professing that trial and error is the best method.
Either 8 jfet of j113, j112 or 2sk170 fill in either slot.
You only need 8 of either.
For 4-8ma... R1 = jumper
If above 8...like in case of j113 and some bl series 170. R1 need find so q2 is about 90 % idss of q1. Typically.. 100 ohm.
Measure MA across R1
Also.... Regards to microphonic
. I was told by people. Who built..
Better to isolate the DC to DC. Mechanical vibration not recommended to be on same board.. Maybe long cable helps idk.
The korg B1 isolate is sometimes not enough.. Need find quite extreme ways to isolate.. Preferably air tight. Kinda similar strategy to build a microphonic tubes. Wood frame with copper is successful I was told. Use a heavy glass top or something.
Maybe some info wrong feel free correct
I've got my B1K finally powered up. All the voltages are correct. But when I connect it between my Brooklyn+ dac and power amp I first get music and after a short while I get a high pitch tone. Anyone any idea what could cause this?
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Wonders still exist: the problem solved itself... Hope the problem stay's away, way too much problems in this world nowadays...
Well the high pitched sound is still there. Sometimes after switching on it takes a short time before it comes audible, sometime it takes more time (30+ minutes). The equipment is as follows: B1K connected to a Holton NXV500 r2. Source is a Auralic Aries G1 connected to a Brooklyn dac+ with separate PS and an Uptone ISO Regen.
Anyone any idea how to solve this?
Anyone any idea how to solve this?
This is a great sounding amp!
When it's not ringing.
I put some foamtape under the Nutube but it did not really solve the problem.
B1K is mounted on a piece of MDF for testing.
Anyone any suggestions what else to try?
When it's not ringing.
I put some foamtape under the Nutube but it did not really solve the problem.
B1K is mounted on a piece of MDF for testing.
Anyone any suggestions what else to try?
My brother had use these to mount the pcb and the ringing stops
Attachments
I tried putting a neodymium magnet on top while having my dmm connected to one channel. Voltage went up from 9,5 to over 13V, then I took it of scared to damage something. Do you think I should try again?
Strange!
I'd try physical isolation first. Rubber grommets, sealed unit, away from speakers etc
Solved the ringing with rubber stand-offs. I was wondering if I can keep the 4 power supply parts in place an insert 24VDC at the indicated point? With the SMPS removed from the pcb.
Don't see any reason why not.
I'd pull the fuse just to make sure AC power doesn't get connected inadvertently in the future without the SMPS module.
The ground will become floating at your new SMPS GND potential, (you lose the path to earth potential without the IEC lead), so you may encounter hum when connected to other earthed equipment, but see how it goes.
If you insert 24v into the +V pad (where the on-board SMPS goes), then you can still have the CLC filter, but the filtering is already pretty good after the 'optional' point, so maybe not needed.
It will be easy enough to try with and without CLC to assess performance.
I'd pull the fuse just to make sure AC power doesn't get connected inadvertently in the future without the SMPS module.
The ground will become floating at your new SMPS GND potential, (you lose the path to earth potential without the IEC lead), so you may encounter hum when connected to other earthed equipment, but see how it goes.
If you insert 24v into the +V pad (where the on-board SMPS goes), then you can still have the CLC filter, but the filtering is already pretty good after the 'optional' point, so maybe not needed.
It will be easy enough to try with and without CLC to assess performance.
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