avr300 said:Especially good if the slowness can be cured. Can anyone pinpoint the slowness - or even better, the cure for it?
Hi,
If you read the TNT article you will find a little jitter experiment on the first page. It seems to be jitter that is responsible for the slow, smooth sound. So I guess an external clock with a clean power supply will do the trick here, as well as better PSU arrangements around the DAC.
Ray.
Hi everyone,
an extremely educating thread, thanks a lot.
I'll order parts right now to cure my CD-67
One suggestion:
When spending so much time AND money to get the best out of these machines,
I see no reason NOT to go for a dedicated custom-made transformer
A custom-made toroid is not that expensive when you order, say, ten of them.
I participated in the group buy for the Pedja Rogic DAC's toroid (made by Antrim)
and worst thing were the shipping charges for those heavy beasts.
Trannies for the Marantz won't be that heavy.
However, with the experience of this groupbuy I tend to say that having toroids
manufactured in Germany and then shipped to the buyers will give significantly
lower prices for everyone - including you in the UK.
This is because of:
- slightly lower prices from the manufacturer
- lower german VAT
- *much* lower shipping
Which voltages and VA-ratings would be needed in addition to those of the standard trannie?
If we can agree on one type of toroid I'd volunteer to ask for some quotes...
an extremely educating thread, thanks a lot.
I'll order parts right now to cure my CD-67
One suggestion:
When spending so much time AND money to get the best out of these machines,
I see no reason NOT to go for a dedicated custom-made transformer
poynton said:
A custom-made toroid is not that expensive when you order, say, ten of them.
I participated in the group buy for the Pedja Rogic DAC's toroid (made by Antrim)
and worst thing were the shipping charges for those heavy beasts.
Trannies for the Marantz won't be that heavy.
However, with the experience of this groupbuy I tend to say that having toroids
manufactured in Germany and then shipped to the buyers will give significantly
lower prices for everyone - including you in the UK.
This is because of:
- slightly lower prices from the manufacturer
- lower german VAT
- *much* lower shipping
Which voltages and VA-ratings would be needed in addition to those of the standard trannie?
If we can agree on one type of toroid I'd volunteer to ask for some quotes...
For a KI it would be more sensible to use the original tranny and add a small one for separate supplies. But for the 63/67/SE/OSE it can be the same tranny.
We will need at least:
3x 9V for clock and DAC supplies??
1x 3,5V for display heaters
2x 9,6VCT for internal 5V and +/- 10V for drivers
2x 17,6VCT for +/-12V for opamps
1x 13,6V for display Vftd
These values are from the 63 schematics and the 67 will also run on that. Since most of the voltages are regulated, they can be rounded off to nice values.
Ray.
We will need at least:
3x 9V for clock and DAC supplies??
1x 3,5V for display heaters
2x 9,6VCT for internal 5V and +/- 10V for drivers
2x 17,6VCT for +/-12V for opamps
1x 13,6V for display Vftd
These values are from the 63 schematics and the 67 will also run on that. Since most of the voltages are regulated, they can be rounded off to nice values.
Ray.
avr300 said:I'll just fire up my Weller.
Especially good if the slowness can be cured. Can anyone pinpoint the slowness - or even better, the cure for it?
Hi,
Altho it's already been addressed, I'd say these things will cure this colouration lot:
- clock (only with good psu) [improves PRAT and solidity a lot]
- hdam bypass [speeds things up, and it's just sublime]
- dc block cap shorting [the bass becomes more free etc.]
As for the 'information' - do most of the things discussed in this thread (yes, it's a lot of work) and you'll be surprised at just how much information there is on CD (I was!).
For the tonal balance/colour etc. I would suggest that's largely down to resistor choices, the op-amps used and their psu bypass caps (perhaps!).
Here is a pic of KI TX
An externally hosted image should be here but it was not working when we last tested it.
