Soft Start Retrofit shutdown for the Paramount

[rayrad]

A while ago purchased and installed Soft Start Retro kits for my Paramount 2A3's I purchased along with a Foreplay III Line Stage Kit and the Extended Foreplay III upgrade kit running Cain & Cain Speakers. Have had the system since 2006.

Soon after operating the system I started having a problem where one of my speakers would start popping and hissing intermittently until it just stopped working. On doing diagnostics, I inadvertently cycled the system on & off without the obligatory waiting period. There is no sound other than background noise now. What repairs do I need to do to repair the damage I have done? Once this fix is implemented I will be coming back for other suggestions after I complete diagnostics (any suggestions?).
/Raymond

 

[Paul Birkeland]

Hello Raymond,

Without knowing which voltages are not within specifications on your amplifier, we will be unable to make anything beyond a random guess as to what happened to your amplifier.

If it's helpful, we can send you a download link to the current Paramount manual that will list all of the voltages and the build steps as though you built them with the soft start from the get go.

-PB

 

[rayrad]

I do have the copy of my Paramount Softstart Retrofit guide to construction with page 38 indicating the target voltages along with my original readings (voltage and resistances). If I retake the readings and find variations in a reading, should that indicate the specific location of the problem?

 

[Paul Birkeland]

Yes, that would be the information that you would want to post here on the forum.  Finding a voltage that's off will help us narrow down what might be going on.

 

[rayrad]

Ok, here we go . . first # is A; second # is B
Terminal nos:
1) 476; 441
5) 97; 220
6) 95; 220
7) 167; 183
9) 169; 183
10) 0; 0
11) 230; 230
12) 160; 162
14) 92; 92
15) 23; 23
16) 492; 458
17) 0; 0
19) 167; 183
20) 0; 0

4 Pin socket
1) 89; 220
2) 485; 440
3) 169; 183
4) 81; 220

9 Pin socket
1) 2.9; 2.9 AC
2) 3.2; 3.3
3) .02; .01
4) 169; 182
5) 0; 0
6) 300; 300
7) Difficult to get to
8)  "          "  "    "
9) 3.0; 2.9 AC

 

[Paul Joppa]

I am disturbed by the Pin 1 - pin 4 voltage difference, which should be 2.5vDC for a 2A3 in Paramount. Your data show 8v on one tube and 0v on the other, probably due to power line fluctuations during the measuring time. If they have equal dull red filament glow then all is fine there.

If the filaments are OK, then at first glance it appears output tube A is toast, with an exhausted cathode. To test this, you can swap the tubes side to side to see if the erroneous voltage at pins 1 and 4 follows the tube.

What is the make and model of the tubes being used? Are they the original 2006 tubes? Some models are more sensitive to the startup transient, and a worn tube will also be more sensitive to this.