I would recommend installing a separate transformer for the analog stage.
Do a bit of tracing and you will be able to find out the traces for the connections that you need to make.
Btw, it is good to buy some spare plastic gears for the Pioneer transport as these gears do wear out over time. Stock them up now as they are still available.
Do a bit of tracing and you will be able to find out the traces for the connections that you need to make.
Btw, it is good to buy some spare plastic gears for the Pioneer transport as these gears do wear out over time. Stock them up now as they are still available.
I'm already thinking about this. As far as I see right now, the V+B/GND/V-B traces are only for the opamps at the analogue outout. Any other experiences?
Very interesting point! What parts do you think of? the wheels made out of white plasics? Excuse the stupid question: Where to buy these parts?
The decoupling caps (C433/434) are polar elkos in the original setup. As far as I understand, non polar types would be more save in this point of the schematic - I don't measure or see any ofset voltages. But I have some very nice elna silmics at hand. Do you think it's save to use them there?
Thank you very much
Floric
Some of the plastic gear parts are prone to wear. It is good to keep spares at home. You can buy them at your Pioneer service centers.
I have bought a bunch of them for a rainy Pioneer day.
The DC offset is sufficiently low for you to remove the coupling caps totally. Try it out and let us know how it sounds.
You can send me more detailed pictures of your 505 and I will have it a good look at them. I don't have a 505 at home. I am using the 904 and 802 as well as the 77.
I have bought a bunch of them for a rainy Pioneer day.
The DC offset is sufficiently low for you to remove the coupling caps totally. Try it out and let us know how it sounds.
You can send me more detailed pictures of your 505 and I will have it a good look at them. I don't have a 505 at home. I am using the 904 and 802 as well as the 77.
Thanks for your answer Ruach,
I measured the DC voltage across the decoupling caps and got 270mV on one channel and 220mV on the other. This was the same after a change of the opamps. In my opinion a bit too much for leaving out the caps. Especially because I try to leave out coupling caps in the rest of my chain.
I think I will increase the value of the resistor in the HP section (R443/444, 22k -> 68k) and decrease the cap value (C433/434 100mu -> 6.8mu) and go for a film cap. This will increase the corner frequency of the HP from 0,07Hz to 0,3Hz. I think that's not critical.
Have a nice weekend
Floric
I measured the DC voltage across the decoupling caps and got 270mV on one channel and 220mV on the other. This was the same after a change of the opamps. In my opinion a bit too much for leaving out the caps. Especially because I try to leave out coupling caps in the rest of my chain.
I think I will increase the value of the resistor in the HP section (R443/444, 22k -> 68k) and decrease the cap value (C433/434 100mu -> 6.8mu) and go for a film cap. This will increase the corner frequency of the HP from 0,07Hz to 0,3Hz. I think that's not critical.
Have a nice weekend
Floric
Hi Ruarch,
now I know which parts you mean. Today my one started jumping an all CDs I inserted. As the jumps were over several seconds on the disc and they appear in the beginning of the disc, I thinkit is a mechanical problem.
So I dismounted the drive and found a couple of white plastic wheels.
As a child I played a lot with "Fischer Technik" the gears supplied with these kits were a lot more stable.
Thank you and best regards
Floric
now I know which parts you mean. Today my one started jumping an all CDs I inserted. As the jumps were over several seconds on the disc and they appear in the beginning of the disc, I thinkit is a mechanical problem.
So I dismounted the drive and found a couple of white plastic wheels.
As a child I played a lot with "Fischer Technik" the gears supplied with these kits were a lot more stable.
Thank you and best regards
Floric
I am not familiar with the S505/605 but the PCB looks almost identical to one of the PCBs inside my S904.
Can you check the voltages of the the power supplies to the analogue stage as well as to the DACs? It may be just +5V and -5V, even to the opamps.
If you are leaving the DC blocking caps in, film caps would be nicely.
The clock is a must and ideally it should come with its own power supply. This should not be too difficult to build. Pioneer's Pulseflow dac chips respond very favourably to clean clock signals.
It is good to keep some spare gears. When you start having inconsistency in tracking during the playback of certain tracks, you may have a worn gear problem.
These gears are not expensive. If you need some, just drop me an email and I can buy it for you at my local Pioneer service centre.
Can you check the voltages of the the power supplies to the analogue stage as well as to the DACs? It may be just +5V and -5V, even to the opamps.
If you are leaving the DC blocking caps in, film caps would be nicely.
The clock is a must and ideally it should come with its own power supply. This should not be too difficult to build. Pioneer's Pulseflow dac chips respond very favourably to clean clock signals.
It is good to keep some spare gears. When you start having inconsistency in tracking during the playback of certain tracks, you may have a worn gear problem.
These gears are not expensive. If you need some, just drop me an email and I can buy it for you at my local Pioneer service centre.
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