Reviving Soundtracs Megas Mix story and noise question
Aug 5, 2015 18:37:22 GMT -6
tonycamphd likes this
Post by Deleted on Aug 5, 2015 18:37:22 GMT -6
Hi guys,
it's been a while, and since i got the Motu 24Ao, it was time to bring consoles back to life for hybrid and analog mixing purposes. We had 2 consoles in the stock room, a Soundtracs Topas Project from my brother and a Soundtracs Megas Mix from me, both retired for some years.
The Topas ran pretty much out of the box. It's an entry level inline console, nice generally, but pretty much a standard thing. It was not in need of any restauration, but well, it is what it is, and after we had it running with the Motu, i became curious about the performance of my modular Megas.
I had to mount everything back, since it resided in boxes and the frame seperately for transportation reasons.
I had it in memory as a pretty rocked to death console. I bought it in an ebay auction for 200 Euros incl. transportation (1000km, it came from Bavaria), so it costed barely more than the transportation on an Euro palette and packaging itself!
Actually, after a bit of cleaning the strips looked quite nice.
Everything mounted - and instantly running. The desk is 26 yrs. old and has obviously not been modified or seen any real service *at all*. ONE channel had a much higher noise, but it has been repaired at 2 traces in a dilettantic way, so it doesn't bother me right now.
But the most annoying: I compared the "16 channel faders at infinity, master at unity" setting noise, and instead of the paper spec of -84 dB it read -47dB on the Tischmeyer Meter in the DAW. WTF!!!
Analyzed the noise, it was mostly 100Hz, 200Hz bump. So something with grounding, i assumed.
Next day, it made a burst noise and -17V rail dead. I opened the "Soundtracs Source" PSU and it's a switcher, at least with nice Elna 'lytes. To take a look at the solder side, i had to unmount it completely. First there are crimp connectors from the power transformer to the pcb and from PCB to console power connector. While disconnecting these (26yrs fuck these things up with corrosion or whatever), 2 solder tails came out of the pcb like butter. One LED simply fell off. It had broken legs due to corrosion from a slight touch! Another one had fallen off, that i noticed later lying in the case, same issue.
While i resoldered the solder tails, and checked the others, another 2 came off.
Everything nicely resoldered, de-fluxed the PCB, also cleaned the component side a bit and back in the box and pray. The momentary price of a new blue-dog PSU is 350 pound plus transportation from UK, and at the moment, we are short on cash.
Powered on and voila - all voltage rails working and the above console spec measurement read -67dB. Grounding issue gone!
I left it on, tested a channel with a mic, printing a test track, working OK.
Left it on another 15 min., out of the room to have a smoke.....
Noise level reduced to -76.5dB.
Hmm. I never bothered to measure the noise specs on this desk before i retired it ~6 yrs. ago.
QUESTION: Considered the desk is 26yrs old without any real service and the paper specs of the brand new console is -84dB at above condition, do you think the -76/77dB in reality now is a bad spec?
I'm thinking about what i probably can do about it, if any. Seems like the old analog console hiss. Doesn't have any annoying specialties.
Pots are in very good (!) shape, buttery, feel like new and no issues. so it *might* be worth it to rework at least *some* stuff....
Also, i have to admit i liked the sound of the console back in the days. it has a very cool low-end behaviour that fit's my taste and sounds warm. Also, i like the EQs (i know, others think they are too limited, but for me, they are totally ok).
Opamps are socketed on all modules, these are the "deluxe" input channels, with the same 4 transistor micpre frontend as the Quartz/Jade lines (which are not bad at all).
Most probably it's not worth to re-cap. Tim, the soundtracs guy, said he never had to recap these, they don't suffer from the issues other desks have. I remember the TAC Scorpion we had in the 90's that was soooo prone to failure in comparison and this and other desks often desperately need recapping nowadays...
Also opamp change would probably make only sense if i try exact replacement with lower noise, same power demand and character. I like the desk sound, no matter what others say, with the old TL072/74's and did try some other opamps on test channels before, and remember i was not happy with the result back in the days...hrmpf. Options, options, options.
Please think loud as well, folks! Ideas? Opinions?
it's been a while, and since i got the Motu 24Ao, it was time to bring consoles back to life for hybrid and analog mixing purposes. We had 2 consoles in the stock room, a Soundtracs Topas Project from my brother and a Soundtracs Megas Mix from me, both retired for some years.
The Topas ran pretty much out of the box. It's an entry level inline console, nice generally, but pretty much a standard thing. It was not in need of any restauration, but well, it is what it is, and after we had it running with the Motu, i became curious about the performance of my modular Megas.
I had to mount everything back, since it resided in boxes and the frame seperately for transportation reasons.
I had it in memory as a pretty rocked to death console. I bought it in an ebay auction for 200 Euros incl. transportation (1000km, it came from Bavaria), so it costed barely more than the transportation on an Euro palette and packaging itself!
Actually, after a bit of cleaning the strips looked quite nice.
Everything mounted - and instantly running. The desk is 26 yrs. old and has obviously not been modified or seen any real service *at all*. ONE channel had a much higher noise, but it has been repaired at 2 traces in a dilettantic way, so it doesn't bother me right now.
But the most annoying: I compared the "16 channel faders at infinity, master at unity" setting noise, and instead of the paper spec of -84 dB it read -47dB on the Tischmeyer Meter in the DAW. WTF!!!
Analyzed the noise, it was mostly 100Hz, 200Hz bump. So something with grounding, i assumed.
Next day, it made a burst noise and -17V rail dead. I opened the "Soundtracs Source" PSU and it's a switcher, at least with nice Elna 'lytes. To take a look at the solder side, i had to unmount it completely. First there are crimp connectors from the power transformer to the pcb and from PCB to console power connector. While disconnecting these (26yrs fuck these things up with corrosion or whatever), 2 solder tails came out of the pcb like butter. One LED simply fell off. It had broken legs due to corrosion from a slight touch! Another one had fallen off, that i noticed later lying in the case, same issue.
While i resoldered the solder tails, and checked the others, another 2 came off.
Everything nicely resoldered, de-fluxed the PCB, also cleaned the component side a bit and back in the box and pray. The momentary price of a new blue-dog PSU is 350 pound plus transportation from UK, and at the moment, we are short on cash.
Powered on and voila - all voltage rails working and the above console spec measurement read -67dB. Grounding issue gone!
I left it on, tested a channel with a mic, printing a test track, working OK.
Left it on another 15 min., out of the room to have a smoke.....
Noise level reduced to -76.5dB.
Hmm. I never bothered to measure the noise specs on this desk before i retired it ~6 yrs. ago.
QUESTION: Considered the desk is 26yrs old without any real service and the paper specs of the brand new console is -84dB at above condition, do you think the -76/77dB in reality now is a bad spec?
I'm thinking about what i probably can do about it, if any. Seems like the old analog console hiss. Doesn't have any annoying specialties.
Pots are in very good (!) shape, buttery, feel like new and no issues. so it *might* be worth it to rework at least *some* stuff....
Also, i have to admit i liked the sound of the console back in the days. it has a very cool low-end behaviour that fit's my taste and sounds warm. Also, i like the EQs (i know, others think they are too limited, but for me, they are totally ok).
Opamps are socketed on all modules, these are the "deluxe" input channels, with the same 4 transistor micpre frontend as the Quartz/Jade lines (which are not bad at all).
Most probably it's not worth to re-cap. Tim, the soundtracs guy, said he never had to recap these, they don't suffer from the issues other desks have. I remember the TAC Scorpion we had in the 90's that was soooo prone to failure in comparison and this and other desks often desperately need recapping nowadays...
Also opamp change would probably make only sense if i try exact replacement with lower noise, same power demand and character. I like the desk sound, no matter what others say, with the old TL072/74's and did try some other opamps on test channels before, and remember i was not happy with the result back in the days...hrmpf. Options, options, options.
Please think loud as well, folks! Ideas? Opinions?
