Findings about material choice
More than 10 years ago i have built several 183's with random selection of materials, using DIY main and output transformers, toroids, anything whatever, folloving the schematic more or less and drifting from it.. To see what is in this schematic and sound after. Core schematic was 183 designed PCB for preamp, adding 4.th tube for dumblelator inside.. 50w , 100w, using NOS tubes very expensive, new and cheap..tried all. Layout and lead dress i didnt follow , it was mine how i meant wires should be in that time. Carbon comp and film everywhere, biased in that way.
50W was built with toroid PT and DIY OPT on "hi fi" laminations, wery wide frequency range.
100W was built on lower grade OPT laminations, with excessive core area for better inductance (bad choice i need to say now). Power transformer on (too) big EI laminations also.
Results were like material random.. 50W amp was very bright, and 100W amp was very dull, on cleans and overdrive too. Sustain, also nothing special. I like drive when AB+ boost engaged this was something + loud, amp showed balls there. Below that or only drive was "only" usable.
I never liked the middle pot range and deep switch / doing nothing special, doing something only at Jazz mode/cutting bass. On Rock some subtle change only.
Also drive from the amps more or less was nothing better than JCM800 Marshall or Soldano SLO type of amps which i preffered then, mostly because they have good enough drive on lower volume which my "Dumbles" didnt.
some pics:
Couple of #183 derivatives
Moderators: pompeiisneaks, Colossal
Couple of #183 derivatives
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Re: Couple of #183 derivatives
100w amp clips
country:
jazz:
crunch:
country:
jazz:
crunch:
Re: Couple of #183 derivatives
sound between 50w and 100w was very diffierent and for me was clear that material means "sound", also there is tranformer construction difference so, OPT + material + maybe lead dress ?
bright 50w amp i left untouched for 10 years.. it had good bass, but lets say some unpeasant highs. middles were not soft and sweet like what i'm hearing in Dumble amps. more like industrial. but it was useful amp.
100w was bass heavy, i blamed my OPT that is "too big" and tried to replace OPT -> bought Classic tone 40-18013, but also with that one (payed expensive shipping and taxes from US) i had too much bass. disapointed, amp left again in that condition for 8 years..i was doing in the mean time some other amps, hi-fi stuff, transformer designing etc. now when im looking at those pics, i see only carbon resistors everywhere but in that moment i didnt see the light
bright 50w amp i left untouched for 10 years.. it had good bass, but lets say some unpeasant highs. middles were not soft and sweet like what i'm hearing in Dumble amps. more like industrial. but it was useful amp.
100w was bass heavy, i blamed my OPT that is "too big" and tried to replace OPT -> bought Classic tone 40-18013, but also with that one (payed expensive shipping and taxes from US) i had too much bass. disapointed, amp left again in that condition for 8 years..i was doing in the mean time some other amps, hi-fi stuff, transformer designing etc. now when im looking at those pics, i see only carbon resistors everywhere but in that moment i didnt see the light
Re: Couple of #183 derivatives
few years ago for one friend i build one more 183.. in some way . chassis and iron donor was Randal RH50T, metal head. i never used that amp so didnt know what to expect.. buy for peanuts. EL34's in the output. good start!
for more gain i have added one more ECC83 because request for channel selectoin was drive/more drive, so anodes MF Dales, cathodes too, guitar was strat so i did classic Fender tone stack 100k slope, 47nf MId, 100nF bass, and arrangement RJ like D. carbon films iskras on the signal path.
after the drive tube (V2) added V3 for more drive! + fx loop all in one!
EL34 output and standard 110k'120k PI.
this was special, not only for gain and character for the gain, but really organic sound, felt on the cleans too! like integrated small chorus in the tone!
some pics , machined frontplate, pcbs build,
for more gain i have added one more ECC83 because request for channel selectoin was drive/more drive, so anodes MF Dales, cathodes too, guitar was strat so i did classic Fender tone stack 100k slope, 47nf MId, 100nF bass, and arrangement RJ like D. carbon films iskras on the signal path.
after the drive tube (V2) added V3 for more drive! + fx loop all in one!
EL34 output and standard 110k'120k PI.
this was special, not only for gain and character for the gain, but really organic sound, felt on the cleans too! like integrated small chorus in the tone!
some pics , machined frontplate, pcbs build,
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Re: Couple of #183 derivatives
more pics from RH50 build , and subchassis for the preamp
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Re: Couple of #183 derivatives
first tube was wired close to the input socket for many good reasons
amp close to the end..
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Re: Couple of #183 derivatives
here what is surprising, sound was from the first powering something special! organic! what lead me to think a lot about it , what are the reasons, because cheap iron is the base and regular D parts inside, little bit more carbon resistors than required 
here is the clip of clean sound of that amp, full of sustain, strong and fast bass, like on piano, very nice highs:
https://www.youtube.com/watch?v=WOm2eqJ2Jok
conclusion that output transformer must be the reason for all that goods + added stage for sustain . drive is also great but i don't have any normal clip of it at the moment! nothing sharp inside, no harshness
here is the clip of clean sound of that amp, full of sustain, strong and fast bass, like on piano, very nice highs:
https://www.youtube.com/watch?v=WOm2eqJ2Jok
conclusion that output transformer must be the reason for all that goods + added stage for sustain . drive is also great but i don't have any normal clip of it at the moment! nothing sharp inside, no harshness
Re: Couple of #183 derivatives
how last couple of years on this great forum can be read about resistor and capacitors change, and this is in line with my observations and experiences.. i have started to look better in pictures, D amps guts, layout, use od coax etc. what is used where and tried to understand why. maybe i can upgrade my couple of amps from beggining of this thread?
in last D generations it is seen a wide variety of material, somewhere metal film on grids and carbon comps on signal, somewhere oposite, carbon films on grids metal films on signal. PI almost always has carbon film for signal and metal film in anodes. somewhere poliester caps for tone stack, somewhere polypropilene on tone stack and PI. looks like there is no standard on positions and looks like D managed to tune the amp for the dedicated guitar. ok, understood so nothing is strict and just is needed to rotate material per positions to achieve the goal.
why is like that-why there is no standard ? for some obvoius reasons (material by hand, availability in the store) but leads me also to conclusion that HAD was not begginer level, so probably because of the output transformer which dictates the sound of the amp, like last filter before the speaker.
HAD used mostly fender transformers which are different by dimensions and internal construction. probably because of that he started to use different material to compensate + players guitar like input generator. something is trivial like using very low noise resistors for sensitive input stage, just common standard, so can be seen some hogher wattage low noise reistor for input grid. also there is seen use of ceramic condensators everywhere for treble circuits (interesting because everywhere you can read opposite, stay away from ceramic).
so i have started to collect material which will be more in D style, like MK3 metal films, draloric carbon comps, ceramic caps those several types X5F, Z5U, Z5F..new from Mouser, old etc.."EJ" parts , cheap but looks like good for the sound?
in last D generations it is seen a wide variety of material, somewhere metal film on grids and carbon comps on signal, somewhere oposite, carbon films on grids metal films on signal. PI almost always has carbon film for signal and metal film in anodes. somewhere poliester caps for tone stack, somewhere polypropilene on tone stack and PI. looks like there is no standard on positions and looks like D managed to tune the amp for the dedicated guitar. ok, understood so nothing is strict and just is needed to rotate material per positions to achieve the goal.
why is like that-why there is no standard ? for some obvoius reasons (material by hand, availability in the store) but leads me also to conclusion that HAD was not begginer level, so probably because of the output transformer which dictates the sound of the amp, like last filter before the speaker.
HAD used mostly fender transformers which are different by dimensions and internal construction. probably because of that he started to use different material to compensate + players guitar like input generator. something is trivial like using very low noise resistors for sensitive input stage, just common standard, so can be seen some hogher wattage low noise reistor for input grid. also there is seen use of ceramic condensators everywhere for treble circuits (interesting because everywhere you can read opposite, stay away from ceramic).
so i have started to collect material which will be more in D style, like MK3 metal films, draloric carbon comps, ceramic caps those several types X5F, Z5U, Z5F..new from Mouser, old etc.."EJ" parts , cheap but looks like good for the sound?
Re: Couple of #183 derivatives
Thanks for sharing your journey Bepone.
My Ods with a early 70-ies Fender Twin OPT is the best sounding one. Smooth high, clear low end.
Coincidence?
Erwin
My Ods with a early 70-ies Fender Twin OPT is the best sounding one. Smooth high, clear low end.
Coincidence?
Erwin
Re: Couple of #183 derivatives
i have no doubt
old technology, paper interlayer insulation , waxed or varnished every layer. parasite capacitance Cp and parasite inductance Ls which dictates bandwith upper frequency higher and can be under control (higher values of Cs than today using modern materials and no wax/varnish/fast winding methods)technology doest exist today or is very expensive (slow winding , need to wait every layer to dry out, 20 min every layer , so one transformer per day = expensive production) but in DIY ... there is time for everything..
Re: Couple of #183 derivatives
i now started to think about correcting my 50w amp.. which was on bright side..the starting situation was like this on the picture, it was some wild build on some wild pcb borrowed from other project etc..
can be seen use of carbon comps everywhere , anodes , cathodes, specially on drive section (i have tried to tame the highs with CC resistors before).. also there are wima blocks instead of electrolytics. there is XICON CF which nowadays i dont like at all. there is blue FKP wima on DEEP switch(FKP!!!) there are Wima polypropilenes on V1b treble peaker system (again 
)
there are polypropilenes Arcotronics on Bass tone stack filter! there is carbon film on NFB.. so many positions are not so D , but some are. reading about ceramic experiences, that highs are more tamed, OD section is better ..i started to think in that way... and started to draw new pcb...
can be seen use of carbon comps everywhere , anodes , cathodes, specially on drive section (i have tried to tame the highs with CC resistors before).. also there are wima blocks instead of electrolytics. there is XICON CF which nowadays i dont like at all. there is blue FKP wima on DEEP switch(FKP!!!) there are Wima polypropilenes on V1b treble peaker system (again )there are polypropilenes Arcotronics on Bass tone stack filter! there is carbon film on NFB.. so many positions are not so D , but some are. reading about ceramic experiences, that highs are more tamed, OD section is better ..i started to think in that way... and started to draw new pcb...
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Re: Couple of #183 derivatives
reconstruction started..on headshell and electronics inside
- new pcbs developed and arranged
- V1 tube moved to the input jack to avoid input coax, long wires, better grounding methods , leading to overall better signal/noise ratio
- tweaked componets selection as much as possible to D standards: Resista MK3's on anodes and cathodes, all elcos in preamp new, signal resistors Draloric carbon films, all treble capacitors X5F ceramics, tonestack 100nF -> 6PS, 47nF mid -> 716, slope 150k MK3, removed MID switch and installed DEEP, Treble cap put fix value, increased 220k before V2a trimmer to 470k carbon film Draloric (for smoother OD) , NFB resistor put Metal oxide type, PI second grid to gnd 47nF-MKT.
- for output tubes g1 resistors remained carbon comps
- power suplly pcb renewed, but kept old elcos to see the difference in the sound only from the preamp
- better lead dress
- headshell painted in acrylic texture paint Duratex to keep the process fast and made some cosmetics
- V1 tube moved to the input jack to avoid input coax, long wires, better grounding methods , leading to overall better signal/noise ratio
- tweaked componets selection as much as possible to D standards: Resista MK3's on anodes and cathodes, all elcos in preamp new, signal resistors Draloric carbon films, all treble capacitors X5F ceramics, tonestack 100nF -> 6PS, 47nF mid -> 716, slope 150k MK3, removed MID switch and installed DEEP, Treble cap put fix value, increased 220k before V2a trimmer to 470k carbon film Draloric (for smoother OD) , NFB resistor put Metal oxide type, PI second grid to gnd 47nF-MKT.
- for output tubes g1 resistors remained carbon comps
- power suplly pcb renewed, but kept old elcos to see the difference in the sound only from the preamp
- better lead dress
- headshell painted in acrylic texture paint Duratex to keep the process fast and made some cosmetics
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Re: Couple of #183 derivatives
more details about electronic parts, like mentioned before V1 pulled to input jack. g1 input stopper is 1W MF Iskra low noise , directly from jack to socket.
resistor combination is mentioned, caps are Orange drops, 6PS, 715 and 716 series, there is difference between them, 715 is more present than 6PS and 716 also has nice qualities, nothing shrill, just nice, i'm mixing them with 6PSs inside the amp -V1b treble peak- ceramic Z5F Mexico in paralell with carbon film /some vintage resistor 220k / wima FKP kicked out
-grid stoppers in V2 metal film
-kept some loop in lead dress for positive feedback (cathode V1a and anode V1b/ in phase)
-output section has built without choke like before , with resistor 470R 5W
-12VDC regulator for heaters V1 and V2 and relays rebuilt, added some heatsink bigger -power supply built with older main elcos but with new diodes / fast HER208
resistor combination is mentioned, caps are Orange drops, 6PS, 715 and 716 series, there is difference between them, 715 is more present than 6PS and 716 also has nice qualities, nothing shrill, just nice, i'm mixing them with 6PSs inside the amp -V1b treble peak- ceramic Z5F Mexico in paralell with carbon film /some vintage resistor 220k / wima FKP kicked out
-grid stoppers in V2 metal film
-kept some loop in lead dress for positive feedback (cathode V1a and anode V1b/ in phase)
-output section has built without choke like before , with resistor 470R 5W
-12VDC regulator for heaters V1 and V2 and relays rebuilt, added some heatsink bigger -power supply built with older main elcos but with new diodes / fast HER208
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Last edited by bepone on Fri May 13, 2022 11:58 am, edited 2 times in total.
Re: Couple of #183 derivatives
reconstruction process is over, amp in the new enclosure and testing can be started..
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Re: Couple of #183 derivatives
where are we? on the sound of 50w? sound was on first playing - spectacular! but really, something impressive!
bass was tight also before, laminations on OPT were high quality , so hi inductance.. i didn't expect nothing less... but now even more attractive! more defined, more strong, i believe due to 715-716 in bass-mid section on tone stack + metal film in anode..
mids became soft and sweet, i believe due to dralorics in signal section (i don't totally follow Draloric hype i just using them last couple of years, but they are better from others, working better for me.. i believe that other good carbon films can lead to that results too, for the moment i know that Iskras were too dark, and xicon useless, dull and boring)
highs- finally tamed. mostly i beleive due to vintage ceramics in treble signal paths!
overdrive, superb, crunch to more gain very useful, not congested, consisting with new effects in the drive, like rotating notes in the chords, this effect wasn't present before. drive and drive+boost now have similar character! one note has thick character, so amp became more blues friendly! very special thing of this amp is when you pick one note, and adding one more, those two start to rotate together with a lot of sustain! pure pleasure!
i have some videos somewhere, but from that moment i became big fan of work and art of HAD! i dont care for other people negative opinions what is possible to read on this site recently , always somebody cries after HAD for some personal wrong perspective..but reality is opposite HAD gave us a lot of thinking, and pleasure after! it is easy to live in this internet era, all is on the table, but very difficult even to copy his work, and you realise that was almost impossible to invent and pick up combination of parts which lead to those result in that time.
sound was on first playing - spectacular! but really, something impressive!bass was tight also before, laminations on OPT were high quality , so hi inductance.. i didn't expect nothing less... but now even more attractive! more defined, more strong, i believe due to 715-716 in bass-mid section on tone stack + metal film in anode..
mids became soft and sweet, i believe due to dralorics in signal section (i don't totally follow Draloric hype i just using them last couple of years, but they are better from others, working better for me.. i believe that other good carbon films can lead to that results too, for the moment i know that Iskras were too dark, and xicon useless, dull and boring)
highs- finally tamed. mostly i beleive due to vintage ceramics in treble signal paths!
overdrive, superb, crunch to more gain very useful, not congested, consisting with new effects in the drive, like rotating notes in the chords, this effect wasn't present before. drive and drive+boost now have similar character! one note has thick character, so amp became more blues friendly! very special thing of this amp is when you pick one note, and adding one more, those two start to rotate together with a lot of sustain! pure pleasure!
i have some videos somewhere, but from that moment i became big fan of work and art of HAD! i dont care for other people negative opinions what is possible to read on this site recently , always somebody cries after HAD for some personal wrong perspective..but reality is opposite HAD gave us a lot of thinking, and pleasure after! it is easy to live in this internet era, all is on the table, but very difficult even to copy his work, and you realise that was almost impossible to invent and pick up combination of parts which lead to those result in that time.