Coupling Cap mod question.

[straightblues]

My question is for a 5E3. Sorry I got it posted in the wrong place.

I want to take some of the low end bass out of the amp. I have read on other posts about changing the .1 uf coupling caps to either a .022uf or .047 uf. (I am new to amp work so forgive my ingnorance.) A couple folks suggested switching out the first two caps. I don't know which ones they are. Also which channel are they going to effect, the normal channel or the bright channel?

The schematic I am looking at ( http://www.hoffmanamps.com/charts/Sc...DELUXE_5E3.pdf ) shows four .1 caps three of which are 400 volt caps and one which is 200 volts.

Can someone please tell me exactely which caps to change please?

Also, which brand caps should I use for this purpose or does it really matter?

Finally, everything I have read says to use caps that are at least 600 volts while the schematic call for lower voltage, why?

Thanks in advance for helping me.

[stokes]

I like the .022 better than the .047,but the .047 will give you an improvement over the .1's.Mallory 150's are good,but there are alot of different opinions as to what would be the "best".I had a bunch of Astron paper in oils I used as well as some Russian military .022's and didnt see a big difference between any of the three.The 400v caps are enough for a 5E3,the 600v recomendation is just an added safety margin,so you can use wichever is easier to put your hands on.Somebody,I think it may have been Bruce,suggested changing the preamp bypass caps from the 22mf to a 1 or 4mf,this works well also,try them both and see what you like.

[I360up]

Crap there is no one on this board. Straightblues if your still out there, looking at the layout on the link you gave...... they would be the first 2 .1uF on the right side of the board.

[straightblues]

I am still out here and haven't done it yet. Thanks for the input.

[stokes]

I would suggest changing all 4 of them.It will affect both channels.I tried changing just the first stage caps as described by I360up,found it sounded better with all 4 .1 caps changed to .022 and the cap in the PI from .02 to .01

[hasserl]

Hey Straightblues! I think your amp has a .047 in the bright channel already, IIRC. We did that to roll off some of the bottom end of that channel, leving the normal channel alone.