102 as Lowplate Classic

[aflynt]

Some clips of the amp with the current round of tweaks (10uF v1 cathode caps, 250k OD trimmer, OD HF Taper set to 188k).

Les Paul
http://youtu.be/dc29A0q_nsI

Strat
http://youtu.be/k_VFLvGMjtY

My playing is kind of off in these, so sorry about that. I'm not sure how well it comes through in the clips, but the amp is much more full, punchy and tactile now. The strings and the speakers feel much more connected. I was initially thinking there may be too much punch with the upped cathodes and trimmer, but A/Bing it with my all-in-one highplate skyliner 102 clone it's pretty much on par with that on the bass front.

All in all it's a great sounding amp now. For higher gain settings I'd definitely dial the HF Taper in for more effect, but at 188k it's perfect for the Stevie stuff with the Strat. As far as the Classic Stack in general, I think I personally prefer the ease of use and refined curve of the Skyliner. I'm thinking low plate skyliner with 10uf v1 cathode caps and HF Taper might be a great traditional blues amp for me. The high plates don't seem to be as clear at low OD settings as the low plates. I like the cleans on all the variations I've tried. The bright on clean relay works really well with the Highplate Skyliner for that.

-Aaron

[aflynt]

One more video of the amp in the tweaked Low Plate Classic Configuration.

http://youtu.be/cLoCJypWziA

-Aaron

[lovetone]

Wow Aaron that sounds killer thats one of my favourite songs and you nailed it, the tone is wonderful.

Thanks for sharing, can I ask what value capacitor you used on the HF taper?

Cheers Geoff

[CHIP]

Sounds great. And so well documented. Thanks.

[aflynt]

Wow Aaron that sounds killer thats one of my favourite songs and you nailed it, the tone is wonderful.

Thanks for sharing, can I ask what value capacitor you used on the HF taper?

Cheers Geoff

Thanks Geoff. It's a .0012 fed by a 500k trimmer set to 188k. I've amended my initial post to include the updated layout:

http://ampgarage.com/forum/download/file.php?id=39044

-Aaron

[martin manning]

Sounds great Aaron! I find the low-plate circuit to be more Strat friendly for sure. I have something close to #124, Skyliner tone stack, and no HF taper. It does have 330p snubbers on the OD stages, though; another way to pare back the highs a bit.

[aflynt]

Sounds great Aaron! I find the low-plate circuit to be more Strat friendly for sure. I have something close to #124, Skyliner tone stack, and no HF taper. It does have 330p snubbers on the OD stages, though; another way to pare back the highs a bit.

Thanks Martin! I was contemplating giving some bigger OD snubbers a shot, but never got around to it. Definitely something to try next time I open up the amp.

-Aaron

[aflynt]

Sounds great. And so well documented. Thanks.

Thanks Chip! I'm hoping the clips, descriptions and layouts can be of help to people like me who are learning about the different circuit iterations and not just white noise.

-Aaron

[Phazor]

Nice Aron, I love the top-end on the little wing clip. Its got plunk and clarity with out the bite. Very nice!

[aflynt]

Nice Aron, I love the top-end on the little wing clip. Its got plunk and clarity with out the bite. Very nice!

Thanks Phazor! Micing the amp seemed to bring out more of the chime. In the room it was a bit darker and dirtier sounding. Low plate definitely does edge-of-breakup well, though.

-Aaron

[Charlie Wilson]

Aaron, your amp sounds great. I think I am getting close with mine. I was not totally happy with the high end on mine both clean and OD. It had a bit of harshness to it. I stared at it for awhile and realized that all of the treble frequencies go through the 500pf bypass ceramic disc sitting on the 220k grid resistor. Up until now, I was using whatever the first ceramic disc was that popped up on the Mouser site but now I am thinking that all ceramic disc capacitors are not created equal. I put a vintage circle D ceramic disc there instead and it really made the treble sound nice. I also tried a Piher 220k 1w resistor on the grid that took me forever to find and I hated it. The bass was overbearing and the mids became very mushy so I put the Xicon 1w CF back and now I am very happy with the sound. I also considered upping the snubbers( I have 270pf) but I like the fact that the HF tapper is adjustable.
CW

[vibratoking]

Certainly everyone has their own taste.

I never liked the HF taper circuit...turns out the guy that originally recommended it doesn't like it either. There's a thread about it somewhere.

Snubbers are another interesting topic. I just can't seem to find a snubber value I like and I've tried many values. Snubbers seem to choke the amp. YMWV.

[Charlie Wilson]

Vibratoking, yeah that is kind of why I avoided upping the snubbers. I like as much high end to sing through the OD as possible. Do you have a preference for a way to trim a little harshness off the top of the OD? I think Robben Ford just backs off on the volume control on his guitar a little.
CW

[aflynt]

I'll have to give some different grid-bypass caps a try at some point. I'm using the orange x5r Sprague caps right now. They LOOK like what HAD used, but who knows if they're constructed the same way.

This amp had a very pronounced dark clean / bright od issue after the lowplate classic conversion. The HF Taper definitely helped as did the bigger V1 cathode caps. It seems like the overall volume balance is better too. I can get the OD ratio way higher than before. Didn't HAD use a HF taper on 123?

The thing I sill don't quite like about the amp is the overall voicing of the tonestack. I can't quite put my finger on it, but there just something not quite right. Like it's missing some upper harmonics or something. It's not the HF taper because it had the same issue before I put that in there and on the clean. Or maybe I've just finally lost my ability to hear those frequencies! I think I'm going to play around with different treble caps and maybe try the 150k slope.

-Aaron

[Charlie Wilson]

I think Stevie had a .002 treble cap.
CW