synthetic
Well-known member
I just ordered OPA277's from TI for this mod, if I had seen the previous post first I would have gone for those OPA4227 instead. (TI didn't have samples of the MC33079, and I am cheap.) Thanks, butta.
Butta's 3630 secret recipe
- Thread starter chrissugar
- Start date
Help Support GroupDIY Audio Forum:
smallbutfine
Well-known member
yeah, TI has DRASTICALLY reduced worthy ic's for free sampling.
At first the audiophools "get for free and sell at ebay for 35$" upgrade opamps. and alot of others, too. mostly expensive types you could buy in 5 pce pack at ebay afterwards...F*CK!!! (sorry, i'm really upset... i was really fair to TI regarding the samples in the past. really sampled only opamps i never tested before or i couldn't find for buying - never made a dime with such...thats more than unethic - its antisocial to do so) :evil: :evil: :evil:
At first the audiophools "get for free and sell at ebay for 35$" upgrade opamps. and alot of others, too. mostly expensive types you could buy in 5 pce pack at ebay afterwards...F*CK!!! (sorry, i'm really upset... i was really fair to TI regarding the samples in the past. really sampled only opamps i never tested before or i couldn't find for buying - never made a dime with such...thats more than unethic - its antisocial to do so) :evil: :evil: :evil:
ebartlet
Well-known member
Let me make sure I understand correctly before I starts swaping parts, the sidechain VCA is getting replaced (2252), not the signal VCA (2150)?
..sidechain is no vca, but RMS-detector..
ebartlet
Well-known member
Oops, I assumed that it was another VCA in the sidechain like the SSL... 
Thanks
Thanks
bluezplaya
Well-known member
I just bought a 3630 on Ebay to mod out. I was going over the parts list before I sent an order to Mouser and I noticed that my board is a Rev. D. I too already have (4) IN4003 diodes. Where can I find these OPA4227's?
Thanks,
Adam
:sam:
Thanks,
Adam
:sam:
bluezplaya
Well-known member
Nevermind I found them at Farnell. Holy Crap that's expensive!!! It better sound great!
:sam: :sam: :sam:
:sam: :sam: :sam:
skipwave
Well-known member
I followed the BlackLionAudio instructions, and used LT1363 in one and LT1359 in another. I think I got all the opamps as free samples from Linear.com. Looks like only the 1359 is available in the quad DIP14 package anymore. My two sound great and get used all the time now. Just wanted to mention this alternative before you spend a bundle on the OPAs.
A side note - Both of mine were RevD, but one had a very crappy board that was a pain to desolder from, the other was sturdy. I think the crappy one was machine stuffed and the other was hand assembled, too. Weird how mass produced items can vary so much in quality.
A side note - Both of mine were RevD, but one had a very crappy board that was a pain to desolder from, the other was sturdy. I think the crappy one was machine stuffed and the other was hand assembled, too. Weird how mass produced items can vary so much in quality.
bluezplaya
Well-known member
Thanks for the heads up! Yeah I changed my mind and was going to get the MC33079's from Mouser with a larger parts order to save a buttload. Have you tried those compared to the ones you have now? And if so, do you recommend the LT1363's?
I am new to DIY and haven't had the experience in knowing what different opamps sound like. I am not new to sound in general, however :wink:
Thanks for the input,
Adam
:sam:
I am new to DIY and haven't had the experience in knowing what different opamps sound like. I am not new to sound in general, however :wink:
Thanks for the input,
Adam
:sam:
skipwave
Well-known member
My thinking on opamp replacement has changed since I started hanging round this forum. I think that the implementation is vastly more important than the model number (provided you have a decent opamp to start with).
The effectiveness of the LT1363 has to do with changing the values of the supporting passive components to best suit this opamp. I don't want to go into the details of the values used, since I bought the plans from BlackLion, and so the specifics are a part of their product, which they obviously worked hard to develop.
Here's a description of the mod. You can buy just the instructions (with VCAs) for $40, see the "Products" page on their site.
http://www.blacklionaudio.com/alesis_3630_mod.html
http://www.blacklionaudio.com/products.html
The effectiveness of the LT1363 has to do with changing the values of the supporting passive components to best suit this opamp. I don't want to go into the details of the values used, since I bought the plans from BlackLion, and so the specifics are a part of their product, which they obviously worked hard to develop.
Here's a description of the mod. You can buy just the instructions (with VCAs) for $40, see the "Products" page on their site.
http://www.blacklionaudio.com/alesis_3630_mod.html
http://www.blacklionaudio.com/products.html
skipwave
Well-known member
If you don't wanna buy instructions, it sounds like Butta swapped in those MC33079 without changing the supporting component values. Also, I'm sure that the folks around here could help figure out how to use another, more readily available opamp instead.
bluezplaya
Well-known member
I totally understand what you're saying and dig your respect for Black Lion. I am going to check into the mod instructional purchase because I believe in supporting the arts as well as science. Being that the 3630 mod is a cost efficient way to get an apparently nice sounding compressor, I would still be way under budget for getting that "big studio" sound by donating a little to Black Lion.
However, I do like the help threads on this forum and find them highly informational .
Adam
:sam:
However, I do like the help threads on this forum and find them highly informational
.Adam
:sam:
skipwave
Well-known member
Right on!
When I did the 3630 mods I was far less experienced (hadn't even found this forum yet) and needed a paint-by-numbers guide. BLA makes a great product that perfectly fit the bill. Now I might be inclined to tinker and experiment more on my own.
When I did the 3630 mods I was far less experienced (hadn't even found this forum yet) and needed a paint-by-numbers guide. BLA makes a great product that perfectly fit the bill. Now I might be inclined to tinker and experiment more on my own.
bluezplaya
Well-known member
Which opamps are replaced on the 3630? TL084? My unit has two of those and a LF347n.
Adam
:sam:
Adam
:sam:
smallbutfine
Well-known member
Replace all three with quality opamps. I prefer Burr-Brown, but others like some AD chips better... just a matter of 'taste'... :wink:
smallbutfine
Well-known member
Just wanted to add that i made very good experiences with opa227 for TL071 and opa228 for TL081 and the respective double/quad versions as a *direct drop-in* replacement many times without any changes aof the surrounding components or massive psu changes (besides the ones i try out generally when i try to upgrade cheapies...).
Kind regards,
Martin
Kind regards,
Martin
smallbutfine
Well-known member
:?:
http://focus-webapps.ti.com/general/docs/sitesearch/searchdevice.tsp?partNumber=opa227
http://focus-webapps.ti.com/general/docs/sitesearch/searchdevice.tsp?partNumber=opa227
SSLtech
Well-known member
I used 4700µF PSU caps (double the 2200µF suggested)
I also didn't see any stability caps at the 7815/7915 regulaors, so I added 100nF ceramics to ground at the input & output of both.
I put a 1µF 50V electolytic from pin 2 (+ve end) to pin 5 (-ve end) of the THAT2252 RMS detector.
Seems pretty reasonable so far...
Keith
I also didn't see any stability caps at the 7815/7915 regulaors, so I added 100nF ceramics to ground at the input & output of both.
I put a 1µF 50V electolytic from pin 2 (+ve end) to pin 5 (-ve end) of the THAT2252 RMS detector.
Seems pretty reasonable so far...
Keith
