Has anybody tried a 250kA OD Level in a Low Plate Classic?

[Charlie Wilson]

Hello, Low Plate Classic guy here again. Has anyone tried a 250kA OD level in the LPC as a way of taming the brightness and increasing the OD gain? I love the clean sound of my amp but I can tell that the OD is going to be a bit of a challenge. I want the OD to be a bit more Rock N Roll(with a Strat ) Right now it is kind of polite sounding and pretty bright. I did a #124 in its original form per Tony's layout. I assumed that the OD trimmer was a 100k but I now also notice that the layout shows the 345k. Maybe #124's original Strat playing owner wanted a meaner sounding overdrive also.

[67plexi]

This is my low plate classic OD 100k trigger pot set to 24k
and 250k audio pot on the back of the amp.


Steve.

[ToneMerc]

I have done a classic with 250K that measured around 212K or so. I would up the OD trimmer to around 45-55K and try that first. While these circuits a great, they sure arent perfect. As far Strats, this is a chapter in itself, my choices are boosting the signal on the front end, build a dedicated amp or use an OD pedal.

TM

[talbany]

Charlie
Increasing the OD level value will do 4 things

1.Add gain
2. Lower the 3dB knee ( beef up the low mids)
3 More low mids= Not as smooth (less sustain)
4 Darken the tone
The more low mids you add to the OD signal the more congested the amp will become affecting how the amp will sustain..If you want/like that low mid snarl edge to it the 250k will get you closer (good for Rock Tones)..it will also help to beef up those single coils some..I recommend a 30% taper 2-35 pot
Good Luck!

Tony

[Charlie Wilson]

Hello guys, Steve I think you have described your amp as "Jazzy" sounding. Does that mean that it lends itself to lower gain type sounds? I am also curious about the pot between the relay and 220k. It looks like it is grounded. Is it for tone shaping? In response to Tonemerc; yeah I have the trimmer at 50k straight up and it sounds pretty good but a bit too bright. I think before I make any changes though, I need to take this thing somewhere and crank it up. I think also I am going to need a Dumbleator for reverb and that may roll a little high end off the OD sound. I really love the clean sound but I did build this for the overdrive so it may become a High Plate Classic (#94) or as suggested by Henry a 120k/150k -150K/220K Classic. I just read Tony's post. I like the sound of what you described. I am playing a rather bright maple board strat. I guess it won't hurt to try it. Thanks guys.

[67plexi]

I have the 2-35 pot in this build but with the 250k pot on the back I can dial in most any overdrive
it's all a balancing act. You said 4 x10'S you may want to try a single 15" or a EVM-12L
I built a ODS amp that I call Black Flag due to the transformers it was way too bright
A Fane Studio 12L solved that problem. A good example I scored a 1960 Fender Concert amp
today and some jackass put a 15" JBL speaker in it. As soon as I put 4 x 10" with a 2 ohm load
instant Freddie King tone. What I'm getting at is try different speakers before you start modifying
your amp. And like Tony said hit the front end with a OD peddle. Then go low plate high plate
since you like the clean channel and I love the sound of #94 What's in that 2 x 12" speaker cabinet ???
And what does that ratio pot do.

[marcos]

Here´s my 2 cents:
Instead of changing the pot,
I would try increasing the V2b coupler to .01 first,
a free experiment without soldering. See how you like it,
Marcos

[ToneMerc]

I recommend a 30% taper 2-35 pot

Tony

That's what I have my LPSLMM , so Charlie PM me your address. You gave the gift of the Tweedle Dee, so I will send you a Fender 70-80's vintage 250K 2-35 pot.

Mike

[Charlie Wilson]

Thanks Marcos, I will give that a try also. I am going to try everything.
CW

[bcook]

Speaking as a LP classic fan (fanatic?), I ended up with 330p as snubbers, but I think they were of better quality than the 270p that I tried. The 270's had a somewhat ragged response to my ear.
Season to taste...

[Charlie Wilson]

Thanks Bcook. Yeah Henry(Redplate) suggested I try 390pf. So I should look into adjusting the snubbers. The guitar I am using is a EJ Strat with stock pickups but replaced trem block and saddles. I thought the stock leaded(steel) block and copper plated saddles made the guitar sound muffled. The guitar is a lot clearer now but also very bright. Last night I was playing through the amp and then through some overdrive pedals that I thought sounded good and the amp overdrive by itself blows them away. So I know there are some good sounds going on with the Low Plate Classic. I just want to try and get a little more gain and trim the high end just a tad. I guess I should add that I do not have a EVM 12L speaker yet nor have I cranked this thing up with the master volume past about 9:00. I also need to try some other guitars through it for reference. One of the perks of working at a guitar shop. Bcook since you are a fan of this circuit, I would love to hear about any other tweeks you have done to yours, what guitars you are using, and were you set our OD entrance trimmer. Mine is set at about 50k right now.
CW

[Charlie Wilson]

One more thing I am wondering about is the 345k trimmer that is on Tony's layout for the Low Plate Classic. Has anyone built this circuit with that value trimmer and is the consensus that value trimmer was in #124 prior to the Skyliner modifications? I ask because the two circuits that I know of that were built for Strat players (#124 and #123) both appear to not have the standard 100k OD entrance trimmer pot value.

[ayan]

One more thing I am wondering about is the 345k trimmer that is on Tony's layout for the Low Plate Classic. Has anyone built this circuit with that value trimmer and is the consensus that value trimmer was in #124 prior to the Skyliner modifications? I ask because the two circuits that I know of that were built for Strat players (#124 and #123) both appear to not have the standard 100k OD entrance trimmer pot value.

There is always room for speculation, I suppose. All I can say is that the higher value trimmer muddies things up too much in my opinion, especially for a Strat. Easy enough to try a higher trimmer in place of the 100K one and decide.

G.

[talbany]

One more thing I am wondering about is the 345k trimmer that is on Tony's layout for the Low Plate Classic. Has anyone built this circuit with that value trimmer and is the consensus that value trimmer was in #124 prior to the Skyliner modifications? I ask because the two circuits that I know of that were built for Strat players (#124 and #123) both appear to not have the standard 100k OD entrance trimmer pot value.

IIRC #123 was built and voiced for a Vintage Strat..IMO if you up the value of the trimmer (Front of the OD) everything I mentioned previous is magnified exponentially (due to the gain stages that follow) I always start at the back of the OD signal chain (OD Level) and work to the front end..we don't know for certian if all Low Plate classics had the larger value trimmers..I would start with a 100k there..

BTW I thought the EJ Strats came with Steel Blocks..Mine did..

Tony

[Charlie Wilson]

Thanks Gil, yeah I may try it but I think I am going to take your word for it. I don't like mud. I know the Stratocaster into a Dumble discussion has been going on for years. The funny thing is that although the Low Plate Classic seems to be the recommended circuit for a Strat, it seems like most the players say that they will continue to play their Strats through a High Plate. I think the first change to the amp I will try AFTER hearing it through a proper EVM 12L speaker at a decent volume with maybe several different guitar types, is to high plate V1 and see if the clean sound will work for me. If I really don't like it, them I will continue with tweeking the low plate circuit. I really don't want this amp to be a low gain overdrive type thing. I love SRV but my Pro Reverb with a Tube Screamer will do that and I am pretty sure this is not the last Dumble type amp I am going to build. Ah just read Tony's post. Yeah, Fender says they are cold rolled steel blocks but ... I put a Callahan steel block in mine and it is night and day difference. I also now for fact that the saddles are plated probably copper. Not saying there is anything wrong with any of that but I like a clearer sounding guitar. The trade off is that it is brighter. As far as your comment about about the trimmer, I think my idea for the 250k Drive pot came from reading a post you made suggesting that increasing the gain AFTER the trim pot is a better way to go.