hello everybody,
i had an nad monitor serie cd 5000.
it never played that much cause i had also a sony
when the sony died, i took the nad, but the nad died very soon after.
i replaced the laser, but the laser wasn't the problem (not very smart of me).
i was thinking of taking it to the dump, but i tried one more time. i started to fiddle with the laser tracking part of the pcb, and without a oscilloscoop i could hear very well what was happening. so after 10 seconds the damn thing was reading cd's perfectly.
so far so good.
i looked at the opamp stage after the dac,
the dac is an mn6471m, after the dac there is an opamp stage as big as st paul cathedral. i count 4 5532 opamps. the player has an fixed and variable out.
I wonder what i can do to get the sound better:
1)replacing the caps: the old are elna cerafine, and look fine although they must be around 18 years or so. there are a lot of caps, so i'm not really looking forward to this.
2)can i steal the Vout from the dac, and put a high quality opamp behind it ?
3)i don't wanna put in a tube cause the costs will be to high for this machine.
i'm planning to get an old philips, with a tda1541 and then put a lamp in it.
so what would do you guys advice,
thanks a lot
i had an nad monitor serie cd 5000.
it never played that much cause i had also a sony
when the sony died, i took the nad, but the nad died very soon after.
i replaced the laser, but the laser wasn't the problem (not very smart of me).
i was thinking of taking it to the dump, but i tried one more time. i started to fiddle with the laser tracking part of the pcb, and without a oscilloscoop i could hear very well what was happening. so after 10 seconds the damn thing was reading cd's perfectly.
so far so good.
i looked at the opamp stage after the dac,
the dac is an mn6471m, after the dac there is an opamp stage as big as st paul cathedral. i count 4 5532 opamps. the player has an fixed and variable out.
I wonder what i can do to get the sound better:
1)replacing the caps: the old are elna cerafine, and look fine although they must be around 18 years or so. there are a lot of caps, so i'm not really looking forward to this.
2)can i steal the Vout from the dac, and put a high quality opamp behind it ?
3)i don't wanna put in a tube cause the costs will be to high for this machine.
i'm planning to get an old philips, with a tda1541 and then put a lamp in it.
so what would do you guys advice,
thanks a lot
hi then_dude
I'm working on a similar mash dac.
some mods:
- use some tl431 for separate voltage regulators (one for analogue, and one for digital section of dac)
- change all electrolytic capacitors with newer ones.
- 5532 is a good old op-amp, you could update them with some $$$ OPAxxx chips
I'm working on a similar mash dac.
some mods:
- use some tl431 for separate voltage regulators (one for analogue, and one for digital section of dac)
- change all electrolytic capacitors with newer ones.
- 5532 is a good old op-amp, you could update them with some $$$ OPAxxx chips
I upgraded Technics 670: Shottky diodes, bigger capacitors (mainly 4700 uF Panasonic FC with 22uF multilayer ceramics bypass) everywhere, replaced opamps (settled for LM 6181 after DAC and OPA 604 in the output, 2200uF FC at socket pins pluss 0,1/0,01 uF bypasses pluss 0,1 uF between rails), built KWAK-clock (thank You, Elso, how are You?), installed a mains connector with built-in filters, damped everything and made base much more massive.
Turned out to be very musical.
Turned out to be very musical.
@ Ola
your KWAK clock drives both the DAC and the transport circuits? Did you use buffers for quartz signal?
@ all
MASH dac seems to be not so good, despite the optimal S/N and THD on the datasheet.
But they begin to sound good if heavily modded.
your KWAK clock drives both the DAC and the transport circuits? Did you use buffers for quartz signal?
@ all
MASH dac seems to be not so good, despite the optimal S/N and THD on the datasheet.
But they begin to sound good if heavily modded.
- Status
- Not open for further replies.