ayan wrote:Interesting because my experience with the 100K amps was, after I was hipped to the higher resistor values, to never bother again... and that was 1999. However, recently I have been told by many people whose opinion I respect that the 100K amps are the "shite." Couple of quotes:
1. "The 100K amps cop the LC tone."
2. "RF's amp was a 100K amp until 'Handful of Blues'"
3. "100K amps totally sing in clean mode"
Of course, I have to admit that #124, which I got to play myself, sounded terrific and as the pictures I took show, it is a 100K amp. So I am scratching my head a bit on this one, wondering if it's worth going back into one of my amps and give the 100Ks another try.
Thanks for all the responses,
Gil
Very interesting topic. I have to admit I lean towards the 100K amps heavily. My experience started around 2000 when I discovered the schematics floating around on the net and Gil's great web site. I built a few amps from the "s3988009" drawing, eventually learning there are mistakes on it, thanks to Gil and later, this forum. I continued to play and tweak a bit but was generally pleased with the sound.
When the 124 came along I rebuilt a 100w to match and so far, definitely prefer it. I feel like it has what I was missing, maybe I'm just more of a "Fender" guy than "Marshall". Also, I play clean more than 75% of the time (no clipping) and I like the OD without PAB and just on the edge (100% HB PUs).
I while ago I tried compairing the two Rp/Rk (lower vs higher) on the 1st two stages (CL1 & CL 2) in the same amp while playing/testing. I think I used 10uf bypass common to both sets of values and just switched resistors using insulated clips (potentially dangerous of course). I was interested to see which clean sound I preferred. The results as best I can recall, led me to much prefer the 100K/1.5K. Attempting to discribe the difference in (clean) sound, I would say the 100K/1.5K has more punch or body or low mid fullness (honk?). This may contribute to the potential for clipping (perceived higher volume) I don't know (adjust the knob on front panel). To me, the higher values seem to make the tone more scooped and compressed maybe this has the effect of reducing clean clipping. YMMV
Pete, you can't do an A/B like that. The bypass caps make such a huge difference. You'd need to use the 10uf on the 100K plates and 4.7uf on the higher ones. Results might still be the same but there are differences besides Rp/Rk. Like CL2 size....
Pete wrote:
ayan wrote:Interesting because my experience with the 100K amps was, after I was hipped to the higher resistor values, to never bother again... and that was 1999. However, recently I have been told by many people whose opinion I respect that the 100K amps are the "shite." Couple of quotes:
1. "The 100K amps cop the LC tone."
2. "RF's amp was a 100K amp until 'Handful of Blues'"
3. "100K amps totally sing in clean mode"
Of course, I have to admit that #124, which I got to play myself, sounded terrific and as the pictures I took show, it is a 100K amp. So I am scratching my head a bit on this one, wondering if it's worth going back into one of my amps and give the 100Ks another try.
Thanks for all the responses,
Gil
Very interesting topic. I have to admit I lean towards the 100K amps heavily. My experience started around 2000 when I discovered the schematics floating around on the net and Gil's great web site. I built a few amps from the "s3988009" drawing, eventually learning there are mistakes on it, thanks to Gil and later, this forum. I continued to play and tweak a bit but was generally pleased with the sound.
When the 124 came along I rebuilt a 100w to match and so far, definitely prefer it. I feel like it has what I was missing, maybe I'm just more of a "Fender" guy than "Marshall". Also, I play clean more than 75% of the time (no clipping) and I like the OD without PAB and just on the edge (100% HB PUs).
I while ago I tried compairing the two Rp/Rk (lower vs higher) on the 1st two stages (CL1 & CL 2) in the same amp while playing/testing. I think I used 10uf bypass common to both sets of values and just switched resistors using insulated clips (potentially dangerous of course). I was interested to see which clean sound I preferred. The results as best I can recall, led me to much prefer the 100K/1.5K. Attempting to discribe the difference in (clean) sound, I would say the 100K/1.5K has more punch or body or low mid fullness (honk?). This may contribute to the potential for clipping (perceived higher volume) I don't know (adjust the knob on front panel). To me, the higher values seem to make the tone more scooped and compressed maybe this has the effect of reducing clean clipping. YMMV
dogears wrote:Pete, you can't do an A/B like that. The bypass caps make such a huge difference. You'd need to use the 10uf on the 100K plates and 4.7uf on the higher ones. Results might still be the same but there are differences besides Rp/Rk. Like CL2 size....
Good point, including the BP caps in the experiment would be better, the results may be more dramatic.
I will also note that my more recent experience was when I saw the gut pic of the LC amp. I completely reworked a 50w back to HRM (not the LC BM). In compairing the two (100w low vals vs 50w HRM), it appears that I'm getting results that still support my veiws (IMHO). Although stll not a fair compairison because it is 50w/100w and as I said, my focus is on clean so I prefer 100W. I need to build more amps, but I'm sensing a feeling like I'm about to step into quicksand, if you know what I mean.
"CL2 size..." Scott, you mean as in .047 mf?? ... same in both amps I'm referring to, no??
The higher plate amps, IMHO, do not have a .05uf. The one amp I saw had a .01uf there!! The HRM has it, but that is a different circuit. The Hybrid A amp had it, but with a 1uf bypass! I know of no 220/150 non-HRM amp that has a .05uf on CL2 with a 4.7uf bypass.
Pete wrote:
dogears wrote:Pete, you can't do an A/B like that. The bypass caps make such a huge difference. You'd need to use the 10uf on the 100K plates and 4.7uf on the higher ones. Results might still be the same but there are differences besides Rp/Rk. Like CL2 size....
Good point, including the BP caps in the experiment would be better, the results may be more dramatic.
I will also note that my more recent experience was when I saw the gut pic of the LC amp. I completely reworked a 50w back to HRM (not the LC BM). In compairing the two (100w low vals vs 50w HRM), it appears that I'm getting results that still support my veiws (IMHO). Although stll not a fair compairison because it is 50w/100w and as I said, my focus is on clean so I prefer 100W. I need to build more amps, but I'm sensing a feeling like I'm about to step into quicksand, if you know what I mean.
"CL2 size..." Scott, you mean as in .047 mf?? ... same in both amps I'm referring to, no??
ElectronAvalanche wrote:The OD was much better (smoother) with the 220k/150k plate resistors, the 100k/1k5 had a harsh sound, that had some holes in the OD. Don´t know how to explain this, but think about a Hiwatt amp distorting (100k/1k5) in comparison to a creamy Marshall (220k/150k/100k/1k5).
Hallo Herr Dominik. You know, I could have writtten the above paragraph based on my recollection of the 1.5K amps. I am still very intrigued that some people think they rule!
Scott L.: when I had the 100K amp (I only built one) I used MB values, which meant a 100K slope resistor, .022uF mid cap, 10uF cathode bypass caps, etc. I remember the overdrive got harsh pretty quickly, and as soon as I went with the higher resistor values, all of that went away.
To all: thanks for participating in this thread, I think it's proving to be very informative.
The higher plate amps, IMHO, do not have a .05uf. The one amp I saw had a .01uf there!! The HRM has it, but that is a different circuit. The Hybrid A amp had it, but with a 1uf bypass! I know of no 220/150 non-HRM amp that has a .05uf on CL2 with a 4.7uf bypass.
I have seen some higher plate amps (non HRM) with .05uF coupling cap on CL2 -- all but one actually. They did have the smaller, 1uF cathode bypass cap on CL2. However, that stuff will make some difference in the low end, but not too much in the "texture" of the overdrive, IMHO. The size of the resistors imparts a much stronger character that cannot be dialed out with coupling or cathode bypass caps.
talbany wrote:I've built a 100w 6L6 version based on #124 w/100k /1.5k in both clean and OD. The thing I liked about it was the shift between clean and OD channel was real transparent, not much of a tonal change other than the OD getting thicker the added gain and compression and a nice singing quality(Talk to you daughter thing). I liked it alot and it being 100 watts the clean channel still had plenty of headroom for me.
++1, yes, I really like that transition clean to OD.
talbany wrote:One thing to note If you use a good bypass cap say the black or silver sprague atoms and not the cheap xicons or nicheons makes a big differance in the smoothness of the breakup. Real noticeable in the clean channel.
Just one man's opinion.
I have a 50 watt non hrm build that was originally built with the higher plate loads. I was never completely happy with the clean sound as I felt it was lacking character, the OD tone was fine.
When #124 information became available I switch my amp to those specs but the OD was too harsh for my tastes. I then switched the PI to the BM values and raised the plates and cathodes for the OD channel and have not looked back.
Its a bastardized version for sure, but my voltages are in line and it sounds great.
keithrick wrote:I have a 50 watt non hrm build that was originally built with the higher plate loads. I was never completely happy with the clean sound as I felt it was lacking character, the OD tone was fine.
When #124 information became available I switch my amp to those specs but the OD was too harsh for my tastes. I then switched the PI to the BM values and raised the plates and cathodes for the OD channel and have not looked back.
Its a bastardized version for sure, but my voltages are in line and it sounds great.
Thanks, I've often thought about trying that.
As for OD too "harsh", this point could cause an uproar but ... did you try something higher for the pre OD trimmer? ... I use 250K with a pretty low setting ... works well for me.
All due respect to Moss and Norm, neither guy has been inside or played a Dumble. I have assisted about a half dozen D'lite owners with OD tweaking and everybody has greatly preferred adding a series .05 before the pre-od network. I stand by my comment that a .05uf coupler on high plate load amps, with 4.7uf bypass, is thuddy and buzzy in the OD (as well as NEVER being documented as being in a Dumble). Reducing bass content smooths things greatly. I am not so sure that the .05uf is current standard D'lite value.
Pete wrote:
dogears wrote:I know of no 220/150 non-HRM amp that has a .05uf on CL2 with a 4.7uf bypass.
O.K., granted. (on a side note, that is the typical D'lite configuration if I'm not mistaken. Just sayin', apparently it's not taboo with everyone)
You know, I could have writtten the above paragraph based on my recollection of the 1.5K amps. I am still very intrigued that some people think they rule!
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