@xcool’s statements are perfect. Love it.
Although the Cary support person is very nice, sometimes he doesn’t give me a straight answer [. . .] He never really answered my question.
“Haha. Yeah. There was a time when I used to rave to anyone who would listen to me about Cary Audio’s telephone tech support. I will say no more on that subject.”
Yes, absolutely right! Now the answers are just cut and paste. Dan and Marc used used to be great on the phones there but there’s no more phone support as many companies are doing. And Dennis Hadd’s statement still holds true and now even more so. The two balance pots are even cheaper ones then they used to use. Years ago they used the Clarostat pots in that position. Then when those got more expensive they change to some very cheap generic pots which are terrible. At least they still use the Alps Blue Velvet in the main volume position.
Also glad you didn’t go for the lower gain mod. Part of that mod is already in your ultimate upgrade when they change the cathode resistors. The rest is simply adding four resistors in the line gain stage to reduce the signal and I didn’t think the preamp sounded as good then. Just lost its life.
If you want to keep the two balance controls and improve the sound quality get a couple of high quality mono pots for that position. Like a couple of the mono version Alps Blue Beauty or better. Or better get the Khozmo or whatever. There isn’t a lot of room there before it hits the pc board so you’ll have to measure things. As I mentioned the value of the pots are stamped on the back of it their values.
Another answer that is better then two pots, find the position that sounds best on the balance pots and, that gives you some master volume adjustment freedom, measure the resistance of the balance pots and install to high quality resistors in there place. That will sound better then most any pot. Of course then you have no control over balance.
What to understand in the way the 05 is that the gain of the tube circuit is set. It’s just on. What you are controlling is how much of the signal coming in from your source you are going to allow to go forward into the circuit and be amplified. Now the balanced input circuit (6SN7 tubes 3&6) of the SLP-05 produce gain also. About 9db on ultimate upgrade units and 12db on a standard one. So the balanced input gets amplified and then routes through the balance controls and then the volume control, then on to the line stage circuit consisting of the four 6SN7 tubes 1,2,4,5. The single-ended inputs route in from the switching relays directly to the balance and volume controls. That is one reason why there is so much gain on the balanced inputs. Along with twice the signal from the +/- phases. I’ve heard of people trying and I’ve tried lowering the gain into the balanced inputs from the source but I’ve really noticed a lack of dynamics and overall sound quality then. They need the +/-2V in for best sound. Another thing to be careful of is how much input goes into the balanced inputs. They overload the tube if you go much more the 2V per phase of the balanced signal. Meaning balanced +2V and -2V. Like once you hit about 2.3V to 2.4V per phase you will start hearing it distort/clip. Things get hard and bright first then fully distort. So be careful of your balanced source components. To understand better, those two tubes are “full on” and there is no volume control in front of them. It was designed in the day when the standard source component output was 2V.
All right sorry! I always explain too much.