cant get much gain from my pv10 or pv12, what am i doing wrong here. tried tube rolling, direct line but still no better. talk with rhp desizn, said he dont think changing out the caps would help volume problem. any one else having this same problem..........
Think back to the time when your system operated exactly as you think it should. Then think of the changes you made and the effect you noticed after you made that change.

I looked at you old thread on this subject. If I understand correctly you have had ALL of the stuff working in your system, amp, pre-amp, speakers and source before you encountered this problem and it only occurred since you started rolling tubes or, perhaps, something else?

Now if you had said that you noticed the 'loss of gain' after you changed the speakers, or the amp, the answer would be easy - that is the speakers were less efficient or the amp had lower input sensitivity both of which would have required some additional rotation in the volume control.

Tube type can affect gain, for an easy example a 12AT is low gain, the 12AU is higher, and the 12AX is highest of the three and the difference is substantial. They are 9 pin tubes, they are of the same size, superficially look the same and can be used (sometimes intentionally) interchangably. I've seen cases where a unit reqired several differing ones and they were put into the wrong sockets causing an unwanted increase in gain or the obverse . So you want to be absolutely sure you are using the correct tube type in the correct position.

If either of these three posibilities have been addressed and are not the problem you might assume that as the gain issue affects both channels you want to mainly look at things that work for both channels at the same time, like rectifiers, power supplies, etc. If you have one handy you might put in a different amp and see if the problem changes. BTW since you have this same problem with both a PV10 and a PV 12, other than causing a problem by using incorrect or misplaced tubes, it is likely the problem occurs downstream.

Now the GOOD NEWS! Having to rotate your attenuator to a 11 to 1 oclock position to get proper sound levels IS NOT a bad thing. In fact in many, if not most preamps, the attenuator (volume control) is operating in its most linear position there.

I don't know if this makes any sense to you but its all I can think of with the information furnished.
thanks for the advice, i think the problem is going to be the speakers. but ive tried other speakers and have the same problem. i only use 12au7 tubes, can my unit handle 12ax, i dont know. but will try other things when i get my other amp back.
let me add, i am in a position were there is problems with the electrical grid. they had to replace the transformer just resentley, and it seems the problem with my home is starting up again. i think there is a ground problem that they dont want me to know about. i was getting feedback of current into my house. i notice when they put in a ground the loudness came back. thats why i stated earlier that i might need a conditioner.........
The original PV10 used 12ax7, 12at7 and 5751, tubes with much higher gain than the 12au7.
You may want to cal CJ with the serial number and ask about the correct tubes for your unit.

Good luck
thanks, ill call ed and ask. i think my came with the ecc82's.
Agree it is the Au vs> the Ax tubes.
Get 12Ax7 tubes and all will be well.
tanks beth, nice to get advice from a female on this topic. so you are saying that 12ax7's wont hurt. another post suggested 6922 amperex.
Don't use a 6922 or variant 6dj8 or 7308! I would resist taking advise from this source. :-)

I just googled this issue - you may do likewise. You will note that the PV 10 and 12 come in three different versions; 1) PV10, 2)PV10A and 3)PV10AL. (Ditto the PV12)

The PV10 uses 12AX7's in V1 & V2, 12AT7's in V3 and V5, and a 5751 in V4. (Ditto the PV12)

The PV10A uses 12AX7's in V1 and V2, 12AU7's in V4 and V5 and a 12AT7 in V3. (Ditto the PV12A)

The PV10AL uses 12AU7's in V4 and V5. The other positions are unused. (Ditto the PV12AL).

The CJ site has a diagram of the tube sockets and designations.

Now all you need to know for sure is which model you are using. Obviously if it is the PV10 or PV12 you are for sure using the wrong tubes. Casousa would be right on!

BTW, I wouldn't suggest that you try to substitute 12AX7's for 12AU7's if the latter is the designated tube for the socket. Much too much gain. The obverse exchange might work well if you have excessive brightness due to a pre-amp/amp interface.

As I mentioned before, if you've got the right tubes in the right sockets relax and enjoy a probable better utilization of your attenuator.
thanks newbe for clearing that up for me..........