Ampeg VH140 Help/Mod idea

[kiehano]

Ok, I bought my VH years ago on a whim and I've always liked it except for a few things about the distortion channel.  It always sounded too harsh to my ears which I've kind of remedied by sticking an EQ in the loop and sucking out as much as I can in the 16khz band.  Kind of gets rid of the solid state "buzz".  I also boost 4khz a little.  Try it!!  I'm interested in a mod to the tonestack.  The clean channel bass control is set at 50 or 60 hz and if I use a pedal in there it just sounds HUGE!  I would like to try to get the bass control on the gain channel pretty close to that.  I could certainly do the mod myself, I just don't know how to track down the components responsible for setting the bass frequency.  Any help would be great.

P.S.  If one suspects that an amp has lost some "oomph" in the low end over time, what would be the 1st thing to check?  Filter caps?

Feel free to e-mail to kiehano@hotmail.com

[phatt]

First I say Welcome :tu:,
Next I say how about a link to Schemo of amp? That will speed the process somewhat.


Re your comment;
P.S.  If one suspects that an amp has lost some "oomph" in the low end over time, what would be the 1st thing to check?  Filter caps?

Try simple things before delving into the abiss
Try cables they do wear out,
Now many pedal changes have you made since first using the amp?
Has it been a while since Changing of strings?

you might add some little things to that list. 8|
Cheers, Phil.

[kiehano]

I'll have to find that pesky usb drive I have with the schem on it.  Should be able to have a link to it today.

[kiehano]

Ok...found it.  For the life of me though, I don't have anywhere I can upload it.  Have an e-mail addy I can send it to?  PM me.  It's the official schem from SLM too.  It's pretty!

[J M Fahey]

Well, ... you can upload it ... here!.
.......................just answer this mail and click "Additional Options" , the "Attach" window opens.
Thanks.

[kiehano]

Site's not letting me post it.     It's a png file but either it's not posting at all or it tells me the file name is already being used or something like that...

[J M Fahey]

You can post almost anything on Rapidshare and post here the link.
Not the best pace, but ... it works.

[phatt]

Hello kiehano,
                   Check the SIZE of the file you are uploading,, 512KB limit.
Rename the file after a failure,, I had the same problem a while back
Phil.

[kiehano]

Ok...Maybe it's because I'm a noob in here, maybe it's because I'm a fool, but I can't seem to get a readable image of the preamp schematic to upload anywhere.  I get nothing but errors from this site, and when I upload it elsewhere, you can't read it.  I've tried multiple formats and no dice.  If someone wants to take a look and try to help me out, just send an e-mail to kiehano@comcast.net and I'll e-mail the whole PDF I have.  It includes all the schems for the preamp, power amps, chorus section, etc etc, along with parts list, layout diagrams, and PC trace diagrams. 

[J M Fahey]

Hi kiehano.
That PDF is 2.5 Megabytes, about 5 times the largest size accepted.
I've extracted part of it:

[kiehano]

You rock...I suck...period!  Thanks.  Sooo...anyone have any ideas? 

[J M Fahey]

Very short answer: play it loud.
That buzzyness and lack of bass oomph mean low volume.
Unless ... what speakers are you using it with?
I'm sorry but your graphic EQ in the loop seems about the best solution available, at least better than messing with the amp which has already been tweaked to death, that's why it sounds so good.

[kiehano]

I have a few cab I plug into here and there.  The matching Ampeg cab loaded with Eminence Legends, a peavey with Sheffield 1290's, Some home built thing that sounds fucking monstrous, and another old peavey with a uh...mixed bag of speakers!  I was just wondering if it was possible to squeeze a little more low bass out of the gain side since I usually tune fairly low.  I usually play droney doom/sluge/stoner *s!!t* with it as as we all know, doom is all about bass!  A standard low E string resonates around 80hz or something like that and since I tune down to C, B, or A (and sometimes in the G-ish range) I was just wondering if it was possible to boost those frequencies (the legends have a useable range to about 65hz) to roughly the same level.  Right now the bass control is boosting/cutting 100hz.  Oh, yes...I'm fully aware that this amp sounds WAAAAAYYYY better when it's turned up.  Right around 2 on the volume seems to be her sweet spot with the legends...and that's pretty damn loud!

[J M Fahey]

Hi kiehano.
That extreme bass response is not my cup of tea, yet I suggest you use one of the channels into guitar speakers, the other one into a big mean 2x15" 4 ohms bass enclosure.
Keep the guitar box on the other channel or you'll "lose" bass, because your brain will have nothing to compare it to.