Interesting subjecft. I was going to posta topic on this subject of **preamps with high gain** = maybe too much gain
Here is my situation,,I just picked up a used Jadis DPL, , has 1 AU + 1AX + a cd buffer stage. anyway,
I had Richard Gray look over the LINE STAGE (Richard says a pre is actaully a line stage with a phono section),, anyway,, he says there are issues with the design,, that the 12AX7 is giving too much gain in the circuit = meaning at just 1/4 turn of vol knob, and the db level is quite significant,,, so I left him the DPL to look over,,,like 1 hours later he writes,,*Ok just did this and that and this,,,** when Richard gets a task, he goes right to it,,although it is a quite simple circuit and lots of open space to work. In 1 hour he had some mods completed...
I will not know the results as my speakers are being repaired, with new voice coils on the Millenniums and 2 of the W18’s need refoaming,,both I plan to do myself, its easy.
, so you may want to ck out if you can mod the 12AX7 toa 12AU7,, a AX has a mu of 100, a AU of 15.
Richard is anxious to have me test it, but can’t till new xovers arrived from Madisound in 2 weeks.
I’l;l posta YT vid when all upgardes/mods are completed.
Send the pre to Richard and have him mod it for you.
Here is my situation,,I just picked up a used Jadis DPL, , has 1 AU + 1AX + a cd buffer stage. anyway,
I had Richard Gray look over the LINE STAGE (Richard says a pre is actaully a line stage with a phono section),, anyway,, he says there are issues with the design,, that the 12AX7 is giving too much gain in the circuit = meaning at just 1/4 turn of vol knob, and the db level is quite significant,,, so I left him the DPL to look over,,,like 1 hours later he writes,,*Ok just did this and that and this,,,** when Richard gets a task, he goes right to it,,although it is a quite simple circuit and lots of open space to work. In 1 hour he had some mods completed...
I will not know the results as my speakers are being repaired, with new voice coils on the Millenniums and 2 of the W18’s need refoaming,,both I plan to do myself, its easy.
, so you may want to ck out if you can mod the 12AX7 toa 12AU7,, a AX has a mu of 100, a AU of 15.
Richard is anxious to have me test it, but can’t till new xovers arrived from Madisound in 2 weeks.
I’l;l posta YT vid when all upgardes/mods are completed.
Send the pre to Richard and have him mod it for you.