Reduce gain on express

[populartsl]

Whats the best way to reduce the gain down a bit. I don't want to lose too much just a bit to make it more usable.

Cheers Karl

[M Fowler]

12AT7 in the V3 phase inverter and or 5751 in V1 or V2.

[funkmeblue]

you could add a"fast/gradual" switch

[crocket]

I have Changed dropper/decoupler string resistor (R26) from 18K to 10K
to raise the voltage of preamp tubes. I noticed this difference between a JTM45 and a 5F6-A circuit and tryed it on my express.

[PlinytheWelder]

+1 on 5751 in V1 or V2 or even a 12AU7...

I like the AT7 in the PI socket, but I don't think it reduces gain there due
to it's low plate resistance interacting with the circuit. It just sounds better, IMO....

[sliberty]

Mine has the 12AT7 in th PI position, and a split plate load resistor, and for me, the gain is just right.

[PCollen]

I have Changed dropper/decoupler string resistor (R26) from 18K to 10K
to raise the voltage of preamp tubes. I noticed this difference between a JTM45 and a 5F6-A circuit and tryed it on my express.

And this reduced the gain ?

[PCollen]

Whats the best way to reduce the gain down a bit. I don't want to lose too much just a bit to make it more usable.

Cheers Karl

You can cut signal level between stages, or reduce stage gain. The former is easier and much more noticeable than the latter.

Cut signal level :

Turn down the volume control

Put 220K between the Treble Control center tap output and the top of the 1M Volume control.

Put 22K between the .0022 uF 2nd stage coupling cap and the top of the 150K 3rd stage grid ref resistor.

[Richie]

drop the feedback resistor from 100k to 47k

[two tone]

I simply deleted the bypass cap of the second
stage cathode resistor,that did it for me,
now I can turn the volume to 11...

[populartsl]

Thanks guys, i'll try a few things mentioned.

Thanks again

Karl

[populartsl]

Is the feedback resistor is the one connected to presence to 8ohm tap. Just want to make sure i correct.

Cheers Karl

[M Fowler]

Yes the feedback resistor is normal 100K you can change it to the 47K as Richie suggested.

[PCollen]

I simply deleted the bypass cap of the second
stage cathode resistor,that did it for me,
now I can turn the volume to 11...

That would certainly do it. Was a change in tone/feel of the amp noticeable ?

I wonder how a 5751 or even a 12AY7 in V1 would work in an Express.
It seems to me that this amp just has too much gain/distortion , or said another way too little headroom, for most people who build it.

[two tone]

I simply deleted the bypass cap of the second
stage cathode resistor,that did it for me,
now I can turn the volume to 11...

That would certainly do it. Was a change in tone/feel of the amp noticeable ?

I wonder how a 5751 or even a 12AY7 in V1 would work in an Express.
It seems to me that this amp just has too much gain/distortion , or said another way too little headroom, for most people who build it.

less gain,smoother tone,
no more need to worry which bright cap to use..
turn up this volume control