Threw In the Towel with the Low Plate Classic

[Charlie Wilson]

Hello, so I've been messing with the Low Plate Classic circuit for quit awhile now and finally decided it wasn't doing it for me. Now it's a High Plate Classic and I think I'm really liking it. It is a more compressed, even sound and a bit friendlier in OD mode with a Strat.
CW

[lovetone]

Hey Charlie

I'm with you on that one, I have built a few low plate ODS amps and always go back to the High plate.

Nice build and choice of components.

[norburybrook]

Charlie,

I went through the same thing on my #124 low plate build , I wasn't that taken with it when I first fired it up. I spent a couple of weeks tweaking things and then eventually just put it to #102 high plate specs and Boom, it suddenly sprang to life.

I like the low plates in the wonderland however, that amps is lovely with a strat.



Marcus

[M Fowler]

Charlie,

I decided to build a 102 and I am definitely going high plate skyliner.

Mark

[Charlie Wilson]

There were things I really liked about the Low Plate Classic. The clean side was pretty nice with a Stratocaster but there is this mid range hump that kind of bugged me. Although I can see why the guys say that this circuit cuts through a large band. The part I had a problem with was the Overdrive. At low volumes a Strat would sound fairly saturated but soon as you start turning up the master it would get cleaner and brighter. I can see why the SRV guys would like this circuit but I'll leave that kind of playing to the experts. I must say though that I did really like it with a Les Paul. If I were doing a classic rock thing or a punk gig(love Joe Strummer) with humbuckers I would have left it alone. With the High Plate I did notice I have less bloom in OD mode. The snubbers are still the LPC 270pf, so maybe when I lower them to the HPC 250pf I'll get a little of that back. The other thing I was pleasantly surprised with is that the High Plate Classic still is fairly bright and chimmey. To my ears it also sounds nicer with the 4 ohm OT/ 8 ohm speaker mismatch than the Low Plate. Although I prefer not to mismatch.
CW

[mojotom]

After building a few amps with low plate (124's and 70's) and liking them a lot I build an experimental chassis as a test bed and tried various setups (123, 183, 102, low/high plate, etc) always coming back to the 102 configuration, with some tweaks. I did work on the PI and was able to coax a good clean with a Fender PI (OD suffered a bit but less than low/highplate).
So for me 102 seems very good and balanced clean/OD bass so I will start there and try to mod the PI at least (BM, D style, Fender).

[norburybrook]

yes and also it makes a difference if it's 100w or 50w. The low plates sound a lot better as 100w amps, the high plates sound equally as good in a 50w format.

But I agree the #102 seems to be the sweet spot for me with the Blues master a good choice for something different. The clip of Joey landreth I posted was a bluesmaster and that sounded mighty fine. I'll add he was using it in 50w mode with the impedance tuned to match the EV cab.



MC

[talbany]

Charlie
This is a common problem with the Singles and the Low plates?..The trade off
The low plates add some nice sparkle to the top end that sounds good with singles (ala SRV)
but feeding that signal back through several more gain stages gives you that mid hump harsher top end..Not as bad with the darker buckers but the singles can be a bit in your face. The reason for the treble bleeder in some Dumbles..The High plates add a nice top mid chime but you lose the sparkle(Everything shifts downward)..You also get more low end and compression from the high plates..Great for OD..The best way I have found to help the low plates in OD in order is
1..Increase the value of the trimmer from 100k (Dumble did 345k)
2..Increase the OD level to 250k
3.Increase the Drive 250K
4 increase V1 bypass to 10uf
You can also lower your voltages a bit 180/185dcV V1
If this does not work raise the OD plates to 150/120k..I have not built one of these but have played one that sounded pretty good!!

These 4 mods lowers the knee and adds gain than just dumping high's (Snubbers/treble bleeders)
Although these changes helps with the EQ the OD is still not as smooth and compressed as with High Plates?..The other option would be to do a 2nd generation w/Skyliner stack!..This is the best D-Style amp that is 100k and both Clean and OD sound the best for my taste (Great amp for slide)

I will say that some people might say or have a low plate that is smoother in OD than a high plate and that's cool but to this day I have not played or built one of these low plate amps yet?
BTW..Low plate amps in OD for me almost always sound better in closed back cabs..Helps with the mid hump thang!!
BTW> Knowing you you may have tried most of these but thought I would post this for others who may want some ideas on what to try if they are close..

Tony

[Charlie Wilson]

Thanks Tony! A couple things I would like to add. To me, the Low Plate Classic seems like one of those circuits that wants to be turned up loud. Also, I must admit I did not try it with a Dumbleator. The extra compression and a little high end roll of might of made it just right. The one thing I didn't really like was the 10uf on the clean. It did fill it out a bit but somehow also made it seem harsh on the high end. One thing I struggle with were I live is saggy AC. Sometimes my amps sound really great and sometimes really bad depending on what other things are sucking power from the 50 year old wiring in the house I live in. Anyway, it is a circuit I may revisit at some point.
CW

[talbany]

Charlie
Sure thing!..Everyone should figure in that when you lower the frequency response or the knee by either increasing cap sizes, pot values of gain sections in preamp the overdrive sound will become more aggressive since the low mid frequencies don't distort as smoothly so you get a kind of saw toothed like sound..Sometimes you can control it with your attack!..Robben is the master at this (think Jing Chi) Perhaps the answer is both shave off the top end just a bit (cable,snubbers,speakers) and add in some low mids somewhere within the OD section (usually at the tail end)...
I will stipulate that my 100k 2nd gen does fill out and smooth up better at the sweet spot which is around gig volumes especially in OD
Sometimes a D-lator can help with those issues if you can slam the C.F in the lator with enough signal to try and generate enough 2nd order to fill out the sound!??..Much like a Plexi would..The trade off would then be how do you like the cleans?..Always something with these amps
BTW..I recently have been gigging with my BM..I like the control of the OD (since I put the HRM on the front> But I find I am constantly turning knobs on that amp when I pick up another guitar..Again..
I feel your AC pain..I play a weekly gig in DC where the AC floats between 100 and 105 depending on who is in the kitchen..Sucks!!


Take Care!

Tony

[aflynt]

I prefer the low plates /skyliner in my main amps which are 100watts with big iron (MM Tweed Twin OT). I like the straight up 102 setup better in my 100 watt with '70s twin iron, though and I keep my original amp in my home studio configured that way. Ironically, I've deviated a lot circuit and setup-wise (running in Jazz mode with gain stages running hotter and overdriving the dlator loop return a bit too) with my gigging amps, but with my SG it sounds more Fordesque than the more stock circuit and RF settings did. You back off on the right hand attack a bit and the notes really breathe and sustain beautifully. Then you plug the Strat/Tele in and you get that great clear top and punchy low and but with that smooth sweetness and sustain too. The lesson for me has been to do what comes naturally and just trust my ears.

-Aaron