I love how ARP was so protective of their circuits potting their circuits, but had no problem ripping off Moog’s intellectual property and used Moog’s filter design.
@@arsenicjones9125 I do not believe it never went to court. Bob and Alan had a chat and Alan promised not to copy Bob's filters as long as Bob did not copy their dual CV keyboard design and that was that.
Boy this brings me back. In 77 I took an electronics design course in hs where we actually designed and made our own pcbs by laying out traces according to what we wanted. A very smelly process with acids and alike.
LOVE all of your commentary and work, thanks for all you do! these videos are so empowering to folks like myself who just want to fix their own stuff and learn. thank you!
I’ve been looking at using SOT363 dual transistors as replacements to matching and thermally coupling TO-92 transistors for the tz81 and tz581 pairs in the schematic
@@Synthchaser did you have to purchase specifically matched dual transistors, check the match on each dual yourself, or did you find that they matched well without having to select for them?
I upgraded the EQ in my mixer to another layout. People told me I also absolutely should replace all the cheap capacitors in the sound path, because Tascam would use cheap capacitors etc. I swapped them for expensive "audio-grade" caps. So I did tests before and after recapping, and it made zero measurable or audible difference. I also first did a prototype of the EQ circuit with cheap caps I had at home, which I had bought in a big box for almost nothing. And I measured and tested it, and compared to the finished product, with a through-hole circuit board, instead of just soldering things all over the place, and with expensive audio-grade capacitors. Again, absolutely no measurable or audible difference. No difference to noise, no difference to THD, nothing. Measurements on capacitors have shows that some capacitor types do have a higher residual charge, and in theory that could make a difference in some usages. But to be honest, I really don't think anyone can hear the difference ever. The funniest thing was that the forum on Gearspace ended up in a flamewar between those who said caps made a difference, and switching opamps would be pointless, and those who swore changing caps would not make a difference, but I absolutely definitely MUST replace the crappy opamps. :-D I didn't replace the opamps. Looked at it, and MAYBE I could lower the noise floor a tiny bit, but basically every single sound source I have had a higher noise floor than the mixer anyway, so that would have been a waste of time. I should make a video on that upgrade...
I repair surface mount PCB''s at my job and its easy with the right tools. Like for instance we use two Hakko soldering irons with the T15-jo2 tip. That plus a heat gun and the flux infused solder braid and we are good to go.
I've de-potted silicone filled sub modules and it worked well, if a bit time consuming. Couldn't these epoxy modules be treated with an acetone bath of several days like we do on the 106 filter/VCA submodules? Great video once again.
I'd argue that SMD components are *easier* to replace than TH. How many times have you taken a soldering iron and braid to a TH IC, only to leave a tiny bit that you missed and that you only notice when you start lifting the pad. A hot air gun and a pair of pliers or tweezers will get up all but the most heat-sunk components. And even then an upside-down clothes iron makes a great hotplate for pre-warming large ground planes. BGAs notwithstanding of course! As for tracks, I guess a larger cross-section *might* make a slight difference, but at these currents and frequencies I'd be surprised if anyone could not only tell the difference, yet alone make any quality judgements.
Also please go off on a rant about device repair ability and the need to enforce consumers right to repair. Now is the time. There’s a ground swell. The FTC issued a report on it. Biden issued an executive order on it. Ppl need to hear about it from everywhere possible. Thanks
Why do Americans insist on saying "sodder", instead of "solder"? You know, like "soldier" without the 'i". I don't get it? Is this another "Aluminium/Aluminum" thing?
Because the L was added back into the word by the British to “Latinize” it and be fancy. However the common word lacked this L (souder). Eventually the spelling standardized but Americans already had an accent so the L was never pronounced.
@@Nervejam No an Englishman was the first to isolate aluminum and he thought it should be called alumium but the French and Germans wanted it to be more fancy and Latin so they insisted it should be aluminium bc alumin was the Latin name for the oxide rock you get pure aluminum from. Well the English guy finally settled on wanting it to be aluminum but the royal society decided they wanted it to be aluminium and the 2 spellings pronunciations have stuck around since. Accents and words are weird fun
I love how ARP was so protective of their circuits potting their circuits, but had no problem ripping off Moog’s intellectual property and used Moog’s filter design.
I love how they went to all that trouble and it didn’t stop them getting sued but they continued to do it on the replacement modules they designed.
@@arsenicjones9125 I do not believe it never went to court. Bob and Alan had a chat and Alan promised not to copy Bob's filters as long as Bob did not copy their dual CV keyboard design and that was that.
Boy this brings me back. In 77 I took an electronics design course in hs where we actually designed and made our own pcbs by laying out traces according to what we wanted. A very smelly process with acids and alike.
LOVE all of your commentary and work, thanks for all you do! these videos are so empowering to folks like myself who just want to fix their own stuff and learn. thank you!
That was great, thanks! Love seeing your videos.
I liked your rant!
I’ve been looking at using SOT363 dual transistors as replacements to matching and thermally coupling TO-92 transistors for the tz81 and tz581 pairs in the schematic
That's what I did in my replacement module. Worked really well.
@@Synthchaser did you have to purchase specifically matched dual transistors, check the match on each dual yourself, or did you find that they matched well without having to select for them?
I upgraded the EQ in my mixer to another layout. People told me I also absolutely should replace all the cheap capacitors in the sound path, because Tascam would use cheap capacitors etc. I swapped them for expensive "audio-grade" caps. So I did tests before and after recapping, and it made zero measurable or audible difference.
I also first did a prototype of the EQ circuit with cheap caps I had at home, which I had bought in a big box for almost nothing. And I measured and tested it, and compared to the finished product, with a through-hole circuit board, instead of just soldering things all over the place, and with expensive audio-grade capacitors.
Again, absolutely no measurable or audible difference. No difference to noise, no difference to THD, nothing.
Measurements on capacitors have shows that some capacitor types do have a higher residual charge, and in theory that could make a difference in some usages. But to be honest, I really don't think anyone can hear the difference ever.
The funniest thing was that the forum on Gearspace ended up in a flamewar between those who said caps made a difference, and switching opamps would be pointless, and those who swore changing caps would not make a difference, but I absolutely definitely MUST replace the crappy opamps. :-D
I didn't replace the opamps. Looked at it, and MAYBE I could lower the noise floor a tiny bit, but basically every single sound source I have had a higher noise floor than the mixer anyway, so that would have been a waste of time.
I should make a video on that upgrade...
I repair surface mount PCB''s at my job and its easy with the right tools. Like for instance we use two Hakko soldering irons with the T15-jo2 tip. That plus a heat gun and the flux infused solder braid and we are good to go.
Excelent work!
great info on your site. Thanks so much for this you should put a high pass filter on your mic though! cheers
Great video , I wish I could learn to fix analog keyboards very interesting subject for me
What's stopping you? Give it a go. Worked for me.
Another great vid, cheers!
Hey! Can you make a video on cleaning / bending the j-wires on the 3620 keyboard? Thanks!
I've de-potted silicone filled sub modules and it worked well, if a bit time consuming. Couldn't these epoxy modules be treated with an acetone bath of several days like we do on the 106 filter/VCA submodules? Great video once again.
I've seen online a page where someone tried it. If I recall he soaked it for months and got nowhere with it.
Amazing !!!
Wouldn't Isopropyl alcohol be a better choice than acetone?
I'd argue that SMD components are *easier* to replace than TH. How many times have you taken a soldering iron and braid to a TH IC, only to leave a tiny bit that you missed and that you only notice when you start lifting the pad. A hot air gun and a pair of pliers or tweezers will get up all but the most heat-sunk components. And even then an upside-down clothes iron makes a great hotplate for pre-warming large ground planes. BGAs notwithstanding of course!
As for tracks, I guess a larger cross-section *might* make a slight difference, but at these currents and frequencies I'd be surprised if anyone could not only tell the difference, yet alone make any quality judgements.
Also please go off on a rant about device repair ability and the need to enforce consumers right to repair. Now is the time. There’s a ground swell. The FTC issued a report on it. Biden issued an executive order on it. Ppl need to hear about it from everywhere possible. Thanks
Why do Americans insist on saying "sodder", instead of "solder"? You know, like "soldier" without the 'i". I don't get it? Is this another "Aluminium/Aluminum" thing?
Because the L was added back into the word by the British to “Latinize” it and be fancy. However the common word lacked this L (souder). Eventually the spelling standardized but Americans already had an accent so the L was never pronounced.
@@arsenicjones9125 Hmm. Maybe. How do you explain "Aluminium", then? Did we sneak an extra "i" in while you weren't looking?
@@Nervejam No an Englishman was the first to isolate aluminum and he thought it should be called alumium but the French and Germans wanted it to be more fancy and Latin so they insisted it should be aluminium bc alumin was the Latin name for the oxide rock you get pure aluminum from. Well the English guy finally settled on wanting it to be aluminum but the royal society decided they wanted it to be aluminium and the 2 spellings pronunciations have stuck around since. Accents and words are weird fun
@@arsenicjones9125 I like it: the French or Germans are to blame! As usual..
@@Nervejam I’m ok w that simplification 🤣