I really like my C-4 and C-85 preamps and always wanted a C-2X. Thanks to fellow AK'er Justrideit I was able to pick one up. I decided to do an RCA upgrade similar to the one I recently did to my C-85. As nice as these preamps are, the POS RCA terminals are the weak link and often cause connectivity issues along with an occasional dislodged ground sleave. Such was the case with Mark's.
I decided to use external threaded terminals on this modification (I used internal on the C-85). This will allow easier dis-assembly of the back panel if that were ever to be required in the future. I have to warn you though, once you get this all together, you will not want to tear it apart!
From Parts Connexion I purchased "Connex" jacks "Tiffany" style, inside chassis mount dsigned for a mounting hole of 12mm (perfect dia for the holes in the Yamaha back plate) .
I decided to use 21 AWG VH Audio's UniCrystal OCC (Ohno Continuous Cast) Copper wire with "AirLok" insulation. It is really tight in the C-2X and this wire is great to work with. It has superb dielectric performance for such a thin insulation. I took careful attention to not mar the solid copper wire surface.
On the C-85 I found out you need to ground the terminals just like Yamaha did in order to avoid any hum feedback. The back plate in particular needs to ground to the PCB at the same location as the stock mechanical screw connection.
The RCA spacing on the Yamaha is tight so you will need to very slightly trim the insulation grommets on the terminals in order to fit it all together. This takes a few trial fit ups to get it right. I'm also adding a FURUTECH Gold lug IEC connector (easy on the dual voltage version of the C-2X)
In order to keep things tidy I joined the grounding lugs prior to assembly. The phono connections each had their own ground to the PCB so that's the way I did it. I made a little solder jig to get the spacing right.
I did a test fit to determine the wire length and then removed the back panel to complete all the wiring to the new terminals.
Connecting the wire to the PCB is strait forward but not for the impatient among us.
Yes it is tight. Just remember you are having fun and just think, no more POS RCA terminals!
It looks just fine. If all the empty stock screw holes bother you, just remember these preamps need better ventilation anyway! You can see the one (white) ground wire I will attach to a chassis screw on the rear panel.
I never listened to the stock C-2X setup (due to damaged RCAs) but will rotate it into my system later today and let you know my conclusions.
I decided to use external threaded terminals on this modification (I used internal on the C-85). This will allow easier dis-assembly of the back panel if that were ever to be required in the future. I have to warn you though, once you get this all together, you will not want to tear it apart!
From Parts Connexion I purchased "Connex" jacks "Tiffany" style, inside chassis mount dsigned for a mounting hole of 12mm (perfect dia for the holes in the Yamaha back plate) .
I decided to use 21 AWG VH Audio's UniCrystal OCC (Ohno Continuous Cast) Copper wire with "AirLok" insulation. It is really tight in the C-2X and this wire is great to work with. It has superb dielectric performance for such a thin insulation. I took careful attention to not mar the solid copper wire surface.
On the C-85 I found out you need to ground the terminals just like Yamaha did in order to avoid any hum feedback. The back plate in particular needs to ground to the PCB at the same location as the stock mechanical screw connection.
The RCA spacing on the Yamaha is tight so you will need to very slightly trim the insulation grommets on the terminals in order to fit it all together. This takes a few trial fit ups to get it right. I'm also adding a FURUTECH Gold lug IEC connector (easy on the dual voltage version of the C-2X)
In order to keep things tidy I joined the grounding lugs prior to assembly. The phono connections each had their own ground to the PCB so that's the way I did it. I made a little solder jig to get the spacing right.
I did a test fit to determine the wire length and then removed the back panel to complete all the wiring to the new terminals.
Connecting the wire to the PCB is strait forward but not for the impatient among us.
Yes it is tight. Just remember you are having fun and just think, no more POS RCA terminals!
It looks just fine. If all the empty stock screw holes bother you, just remember these preamps need better ventilation anyway! You can see the one (white) ground wire I will attach to a chassis screw on the rear panel.
I never listened to the stock C-2X setup (due to damaged RCAs) but will rotate it into my system later today and let you know my conclusions.
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