slothproductions
New member
Hello
When troubleshooting a 500 DIY module (Hairball Audio FET/500 rev. D comp), I think I just shortened my 500 Series Rack (Rupert Neve R6)….
While the unit was connected to the rack with a Sound Skulptor XT500 extender cable, and I was measuring input VAC on pin 8 and 10, I accidentally slided one of the DMM probes onto the smaller ribbon-cable connections just above (shown in the attached image), and the current draw meter on my R6 peaked . As far as I saw and remember, it was all the way up to the max at 1000 mA. There was no smoke when this happened, and no components seems to have suffered (at least on the outside).
Now, when I plug in my Sound Skulptor MP573 preamp with a dynamic mic (SM7B), I can only get a very, very, very low and thin output with noise all over the place, by cranking up all gain knobs on both the preamp and the Scarlett 18i20 interface. I’ve attached a sound example here: https://shorturl.at/scp7w
The pre is only working with the dynamic mic and not a condenser, and I don’t get any +48V signal when measuring across pin 13 and 15 on the 500-extender; I guess the +48V is dead?
I have tried switching the units to the other slots, but its the same no matter which one I choose.
I tested the internal psu and it outputs 12V to the In/Out board just as it should.
I tried making the general power check, setup and troubleshooting for my MP573-preamp and the values are spot on the ideal ones. This included a general power check (showed 24,2 VDC as it should), bias adjust (3,0 VDC - right value) and DC voltages in different spots on the pcb (every value matched the target ones). The MP573 derives 24V from the +/-16 with a linear regulator, so it seems that the +/-16 from the lunchbox is working like it should, since I get 24,2 VDC in general power check, and at the same time is able to measure 32 VDC across pin 14 and 12.
When inserting my DIYRE OLA5 compressor and Sound Skulptor EQ573-II equalizer, everything works; it is only when recording through the preamp that I encounter the issue.
I can still measure the VAC across pin 8 (In-) and 10 (In+) when sending a 1kHz test signal from my DAW.
Since the psu is outputting +/- 12VDC to the In/Out-board on the back of the chassis and also delivers +/- 16 VDC to my units, I assume/guess that the problem could be related to some kind of circuit on the connection board that steps up to +48 VDC?
I think Im on the right path, but Im quite stuck identifying what could cause the issue in the circuit on the In/Out board.
Does anyone by any chance have a clue or idea about this? Any help or nod in a direction would be very much appreciated.
Several pictures are attached.
Cheers
When troubleshooting a 500 DIY module (Hairball Audio FET/500 rev. D comp), I think I just shortened my 500 Series Rack (Rupert Neve R6)….
While the unit was connected to the rack with a Sound Skulptor XT500 extender cable, and I was measuring input VAC on pin 8 and 10, I accidentally slided one of the DMM probes onto the smaller ribbon-cable connections just above (shown in the attached image), and the current draw meter on my R6 peaked . As far as I saw and remember, it was all the way up to the max at 1000 mA. There was no smoke when this happened, and no components seems to have suffered (at least on the outside).
Now, when I plug in my Sound Skulptor MP573 preamp with a dynamic mic (SM7B), I can only get a very, very, very low and thin output with noise all over the place, by cranking up all gain knobs on both the preamp and the Scarlett 18i20 interface. I’ve attached a sound example here: https://shorturl.at/scp7w
The pre is only working with the dynamic mic and not a condenser, and I don’t get any +48V signal when measuring across pin 13 and 15 on the 500-extender; I guess the +48V is dead?
I have tried switching the units to the other slots, but its the same no matter which one I choose.
I tested the internal psu and it outputs 12V to the In/Out board just as it should.
I tried making the general power check, setup and troubleshooting for my MP573-preamp and the values are spot on the ideal ones. This included a general power check (showed 24,2 VDC as it should), bias adjust (3,0 VDC - right value) and DC voltages in different spots on the pcb (every value matched the target ones). The MP573 derives 24V from the +/-16 with a linear regulator, so it seems that the +/-16 from the lunchbox is working like it should, since I get 24,2 VDC in general power check, and at the same time is able to measure 32 VDC across pin 14 and 12.
When inserting my DIYRE OLA5 compressor and Sound Skulptor EQ573-II equalizer, everything works; it is only when recording through the preamp that I encounter the issue.
I can still measure the VAC across pin 8 (In-) and 10 (In+) when sending a 1kHz test signal from my DAW.
Since the psu is outputting +/- 12VDC to the In/Out-board on the back of the chassis and also delivers +/- 16 VDC to my units, I assume/guess that the problem could be related to some kind of circuit on the connection board that steps up to +48 VDC?
I think Im on the right path, but Im quite stuck identifying what could cause the issue in the circuit on the In/Out board.
Does anyone by any chance have a clue or idea about this? Any help or nod in a direction would be very much appreciated.
Several pictures are attached.
Cheers
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