Sansui 1000, Phono stage soft and muddy

[adreniline]

I have a Sansui 1000, 25E5 are the output tubes, just to let you know. I have replaced the caps in the phono preamp section. The sound is the same as if I had done nothing, volume needs to be higher than normal and the sound is lacking the fullness it should have. The receiver is quite capable of producing sweet music, CD player on aux. input sounds fantastic, even possibly better than my Fisher 500B. Anybody got any ideas, my knowledge is truly limited as far as electronics go, I have been into vintage electronics for about a year and a half and love it, so what I don't understand today I will soon. I have a schematic and have spent many hours staring at it. Thanks all

[mhardy6647]

What turntable and cartridge? The problem could be upstream...

[adreniline]

Thorens TD125 and Sumico Black Pearl @ 5.0 mv. Its not the turntable its the phono stage for sure, my Fisher 500B plays beautiful music with this tt.

[jcmjrt]

You replaced the caps. Did you check the resistor values at that time? Resistor values are critical for phono stages....none of this plus or minus 10% stuff. You want 1%. And the tubes for the phono section?

[adreniline]

No I didn't check the resistors, all part of learning how o fix this equipment I guess. I swapped out the tubes with others just cover the possibility of bad tubes. Trial without error is the only way I am able fix this myself, thank goodness I have good workmanship standards, I just go slow till I can figure this out, any help is greatly appreciated. I uploaded a low res schematic a few weeks ago if you want to have a look at it. http://www.audiokarma.org/forums/attachment.php?attachmentid=98142&stc=1&thumb=1&d=1215234738

[adreniline]

Sorry about that image lets try this its alot better, I have a proper hi res schematic if anybody wants to have a look at it http://www.audiokarma.org/forums/showthread.php?t=172670&highlight=Sansui+1000