Pudu
Headphoneus Supremus
- Joined
- Oct 1, 2009
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I even gave her two shiny, new bulbs less than a week ago. You'd think that would buy me a little sumpthin sumpthin ...
I even gave her two shiny, new bulbs less than a week ago. You'd think that would buy me a little sumpthin sumpthin ...
I finally finished restoring my 2270.
While it sounded pleasant before the upgrades, it had the typical warm Marantz sound with rolled off treble, and also a problem with intermittent static.
The static was eliminated after replacing the differential pair, outputs and the daisy heatsink transistors.
All of the electrolytic caps were subbed (mostly with Elna Silmic II), generally following the suggestions of Patfont in the Electrolytic Cap Shootout Thread on AK. Main filters were Mundorf M-Lytic 10,000uF (bypassed by 2uF Vishay/Sprague PP film caps).
The following pre-amp, power and amp boards had all of the resistors changed to Vishay/Dale 1% metal films: p400, p450, p750, p750, p800.
Film caps (and low value electrolytics) were changed to mostly orange drops and some Panasonic and Vishay (all PP films).
New relay.
Trimmer resistors were swapped.
Headphone out dropping resistors changed to low noise wirewounds.
Main in/Pre out jumpers internally bridged.
Modern speaker binding posts.
New AUX jacks.
All sixteen lamps changed to LEDs.
Offset, bias voltage and current set to factory specs.
300 hours of burn-in later, it now sounds like a totally different receiver. Before, on a 1 to 10 scale of cold to warm, it rated around 8. Now, I would say 5.5. The treble sparkles, much better detail, transparency and bigger soundstage. The bass is tighter and extends further.
Possible future upgrades: diodes and transistors on power and amp boards and of course a wooden case.
I finally finished restoring my 2270.
I finally finished restoring my 2270
...
Headphone out dropping resistors changed to low noise wirewounds.
...
Possible future upgrades: diodes and transistors on power and amp boards and of course a wooden case.
I finally finished restoring my 2270.
While it sounded pleasant before the upgrades, it had the typical warm Marantz sound with rolled off treble, and also a problem with intermittent static.
The static was eliminated after replacing the differential pair, outputs and the daisy heatsink transistors.
All of the electrolytic caps were subbed (mostly with Elna Silmic II), generally following the suggestions of Patfont in the Electrolytic Cap Shootout Thread on AK. Main filters were Mundorf M-Lytic 10,000uF (bypassed by 2uF Vishay/Sprague PP film caps).
The following pre-amp, power and amp boards had all of the resistors changed to Vishay/Dale 1% metal films: p400, p450, p750, p750, p800.
Film caps (and low value electrolytics) were changed to mostly orange drops and some Panasonic and Vishay (all PP films).
New relay.
Trimmer resistors were swapped.
Headphone out dropping resistors changed to low noise wirewounds.
Main in/Pre out jumpers internally bridged.
Modern speaker binding posts.
New AUX jacks.
All sixteen lamps changed to LEDs.
Offset, bias voltage and current set to factory specs.
300 hours of burn-in later, it now sounds like a totally different receiver. Before, on a 1 to 10 scale of cold to warm, it rated around 8. Now, I would say 5.5. The treble sparkles, much better detail, transparency and bigger soundstage. The bass is tighter and extends further.
Possible future upgrades: diodes and transistors on power and amp boards and of course a wooden case.
Thanks guys. I'm still recovering from the solder fumes, haha.
Given all the other changes I can't quantify how much the noise floor dropped from the wire wound dropping resistors. I've noticed from past projects that there is a noticeable cumulative effect from swapping these resistors AND updating the RCA jacks AND installing a high quality connector between the main in/pre out jacks (I've used a DIY 2 inch long silver plated copper cable in a 3 braid with Neutrik RCA plugs).
It's interesting to think about how all of these changes might combine to form the overall sound. I think in this case there are 3 main factors:
The warm(ish) Elna Silmic II caps
The detail and transparency of 1% metal film resistors
All of the polypro film caps that open up the sound and extend the treble(?)
Picked this up today, $40 at Salvation Army. One can of DeOxit later, and she's up and running!
(Onkyo TX-2500 mkII)
Sounds great with my HD650s, and inexplicably drives my Magnepans better than my Denon AVR-3805 (160 wpc at 6 ohms)