Hi everyone
These days I was reading some interesting posts on Diy Audio regarding the Rotel RCD 1070 even if 20 years have passed, I'll explain the matter to you,
I still have 2 players at home
1 CD Rotel 1070 and 1 Rotel Rcd 1072, first of all I wanted to give my opinion on the 2 devices which I find fantastic but I find that... the 1072 sounds more open, better than the 1070,
the Rotel 1070 mounts the OPA 2604
the Rotel 1072 features OPA2277
now, I would like the 1070 to sound like the 1072, my question is: can I buy OPA 2277s and mount them in the 1070 RCD?
Do you think this is enough, or is there something else I could do to try to improve it to bring it closer to the sound of the 1072?
These days I was reading some interesting posts on Diy Audio regarding the Rotel RCD 1070 even if 20 years have passed, I'll explain the matter to you,
I still have 2 players at home
1 CD Rotel 1070 and 1 Rotel Rcd 1072, first of all I wanted to give my opinion on the 2 devices which I find fantastic but I find that... the 1072 sounds more open, better than the 1070,
the Rotel 1070 mounts the OPA 2604
the Rotel 1072 features OPA2277
now, I would like the 1070 to sound like the 1072, my question is: can I buy OPA 2277s and mount them in the 1070 RCD?
Do you think this is enough, or is there something else I could do to try to improve it to bring it closer to the sound of the 1072?
OPA2604 is a much better OPAmp, compared to OPA2277.
If you look closely, you'll realise that Rotel used different analog stage sound coupling caps. They can make a fair amount of difference. I really liked the BlackGates C-type 4.7uF for the sound coupling duties... but they are long gone...
I modified a few of these Rotels... they responded very well to an external clock oscillator powered by a separate low noise +5V supply (separate transformer as well...). The crystal oscillator signal was (quite successfully) distributed via a 74HCU04 inverter (used here as a buffer), so the low noise +5 V rail should power this IC as well.
Re OPAmps.... try the OPA2828. That will sound good.
If you look closely, you'll realise that Rotel used different analog stage sound coupling caps. They can make a fair amount of difference. I really liked the BlackGates C-type 4.7uF for the sound coupling duties... but they are long gone...
I modified a few of these Rotels... they responded very well to an external clock oscillator powered by a separate low noise +5V supply (separate transformer as well...). The crystal oscillator signal was (quite successfully) distributed via a 74HCU04 inverter (used here as a buffer), so the low noise +5 V rail should power this IC as well.
Re OPAmps.... try the OPA2828. That will sound good.
Hi Extreme Bucky
thank you very much, this information is very precious for me, it was what I wanted to hear, regarding the coupling capacitors, I can replace them, I'll see if I can find the Black Gate ones, while as regards the addition of a card and a power supply dedicated to 5 volts, I would also like to try this modification, can you tell me something more, is this card already made? can you tell me where I can find it?
After these changes, do you recommend that I also replace OPA 2604 with OPA 2828?
Thanks again, I hope you have a good day
Maurizio Cappelli
thank you very much, this information is very precious for me, it was what I wanted to hear, regarding the coupling capacitors, I can replace them, I'll see if I can find the Black Gate ones, while as regards the addition of a card and a power supply dedicated to 5 volts, I would also like to try this modification, can you tell me something more, is this card already made? can you tell me where I can find it?
After these changes, do you recommend that I also replace OPA 2604 with OPA 2828?
Thanks again, I hope you have a good day
Maurizio Cappelli
You can search for 16.9344MHz low-jitter eternal clock oscillators. I am not sure if TentLabs XO2.2 is still available, send them an e-mail.
https://www.tentlabs.com/Components/cdupgrade/xo2xo3/index.html
You could also search these forums... I'm sure you'll find DIY-ers who still make these boards.
The power supply is very important; try a nice linear power supply with choke input, followed by LT3045 final stage. Here's one that will work well in powering the clock oscillator PCB and the 74HCU04.
https://www.ldovr.com/product-p/lt3045-1a0g.htm
Re OPAmp replacement... Install DIL8 sockets and then try and see what works for you. There are many options available....
https://www.diyaudio.com/community/...er-than-the-lm4562.308014/page-4#post-7454907
https://www.tentlabs.com/Components/cdupgrade/xo2xo3/index.html
You could also search these forums... I'm sure you'll find DIY-ers who still make these boards.
The power supply is very important; try a nice linear power supply with choke input, followed by LT3045 final stage. Here's one that will work well in powering the clock oscillator PCB and the 74HCU04.
https://www.ldovr.com/product-p/lt3045-1a0g.htm
Re OPAmp replacement... Install DIL8 sockets and then try and see what works for you. There are many options available....
https://www.diyaudio.com/community/...er-than-the-lm4562.308014/page-4#post-7454907
Hi Extreme Boky
Thank you, your advice is very useful and precise
Thinking about it, I decided that I would first like to work on the coupling capacitors and the OPA and then see how it goes, I'll let it run in for a while
Here I have the electrical diagram of the RCD 1070, but not that of the RCD 1072, so I would like to study it and understand what the electrical differences are between the two. Can I ask you for the electrical diagram of the RCD 1072? I would be very happy if you can give you my email maurimauricap@gmail.com
a happy day to you
Thank you, your advice is very useful and precise
Thinking about it, I decided that I would first like to work on the coupling capacitors and the OPA and then see how it goes, I'll let it run in for a while
Here I have the electrical diagram of the RCD 1070, but not that of the RCD 1072, so I would like to study it and understand what the electrical differences are between the two. Can I ask you for the electrical diagram of the RCD 1072? I would be very happy if you can give you my email maurimauricap@gmail.com
a happy day to you