schneiderhan
pfm Member
I have asked Mike P of this forum to fix various bits of gorgeous but now venerable pieces of hifi in the past (e.g. a number of Sony cd players) and he's always done a great job, great comms, great workmanship. But hey you know that already.
Anyway here was a nice challenge for him, a Marantz DA12. I bought this plus the matching CD12 back in 2009 for a really good price. I did have to go to Scotland to get it but that's just par for the course really isn't it. Plus cd players don't like being shipped around. I have enjoyed it very much but decided it probably needed a bit of attention now that it's 30+ years old. Mike had already worked on the CD12 and working on this machine would also give him a chance to see how many of the changes made to the prototype he owns did in fact make it into final production (answer, pretty much all of them).
The thing about this DA12 is that it was modded by Siltech in the 90s. I didn't have much info on the mods other than I knew the XLR outputs had been disabled (which didn't bother me). Nonetheless was a bit of a surprise when Mike started work and was mainly horrified by what he saw! Most of all by the butchered output connections pcb board (to fit new RCA sockets) and the removal of the entire balanced output board including transformers, replaced by a bank of extra power supply filter caps connected to the original filter caps by flying leads. Other changes: -
Various messages followed showing Mike's happiness at reversing the mods ('the caps held in with the hot-melt glue practically fell out'), and painstaking work to remove the glue and replace corroded wire links. Mike can probably say better which caps were replaced with what but there's a mixture of Nichicon, Elna Cerafine and (mainly) Elna Silmic e.g. in the DAC board (to make the most of the sweet and smooth sound of the DA12). And then a debate about whether to swop out the AD711s for JRC5534Ds - eventually deciding to keep the AD711s there for now. And there we have it, one DA12 ready to go and sounding fantastic, noise floor lowered, creamy tonality retained and with more inner detaii. It's probably got more break-in to go but Mike happily described it as the least digital sounding digital source he'd ever heard.
What a joy it is that there are people like Mike that can keep this wonderful classic gear running.
Pics to follow.
Anyway here was a nice challenge for him, a Marantz DA12. I bought this plus the matching CD12 back in 2009 for a really good price. I did have to go to Scotland to get it but that's just par for the course really isn't it. Plus cd players don't like being shipped around. I have enjoyed it very much but decided it probably needed a bit of attention now that it's 30+ years old. Mike had already worked on the CD12 and working on this machine would also give him a chance to see how many of the changes made to the prototype he owns did in fact make it into final production (answer, pretty much all of them).
The thing about this DA12 is that it was modded by Siltech in the 90s. I didn't have much info on the mods other than I knew the XLR outputs had been disabled (which didn't bother me). Nonetheless was a bit of a surprise when Mike started work and was mainly horrified by what he saw! Most of all by the butchered output connections pcb board (to fit new RCA sockets) and the removal of the entire balanced output board including transformers, replaced by a bank of extra power supply filter caps connected to the original filter caps by flying leads. Other changes: -
- Opamps on the main DAC board changed from JRC5534D to AD711JN.
- RCA sockets changed and the wiring leading to the RCA sockets replaced and all hard wired in.
- Output coupling caps bypassed with small value axial poly film caps.
- The two big filter caps bypassed with small value axial poly film caps.
Various messages followed showing Mike's happiness at reversing the mods ('the caps held in with the hot-melt glue practically fell out'), and painstaking work to remove the glue and replace corroded wire links. Mike can probably say better which caps were replaced with what but there's a mixture of Nichicon, Elna Cerafine and (mainly) Elna Silmic e.g. in the DAC board (to make the most of the sweet and smooth sound of the DA12). And then a debate about whether to swop out the AD711s for JRC5534Ds - eventually deciding to keep the AD711s there for now. And there we have it, one DA12 ready to go and sounding fantastic, noise floor lowered, creamy tonality retained and with more inner detaii. It's probably got more break-in to go but Mike happily described it as the least digital sounding digital source he'd ever heard.
What a joy it is that there are people like Mike that can keep this wonderful classic gear running.
Pics to follow.
Last edited:
