Opinions on aamp design most welcome...!

[tonequester]

tonequester here.'I find myself thinking off my first build more and more. Does anybody have an opinion on doing a "Class A". single ended(2output tubes in parallel) using
EL-84'sCathode biased ? All relpies greatly appriciated. I don't even know if a kit exists for this, as of yet. Tonequester out, for now, hopefully not out for the count !

Quote : "I have already learned fron the forum, that he "science' of tone depends more on opinion than the numbers. tonequester.

[Chuck H]

It probably depends more on the styles of music you want to use it for than anything else. And we don't have that piece of information. Actually, more than style of music, since everyone has their own sound in their head, it might be better to know things like who's sound you like, how much you want to overdrive it or if you want a master volume/uber gain thing, do you need an effects loop or are you a plug and play guy? Reverb? Trem? Amps do A LOT of things. What do you want your amp to do?

I could certainly tell you what I would build for myself in a ten watt class A, single ended amp (I can even dress myself and tie my own shoes!). But nobody can tell you what you want. So, since the opening post sort of reads 'What do I want?', you might do better to tell us what you want and ask how to get it.

[Gingertube]

Assuming that you are set on a Single Ended design then there are better options than paralleling 2 off EL84. The tube (in my own opinion at least) which is closest to the EL84 sonically is not it's big brother the EL34 as most folk might think but rather the KT88. A single KT88 will give more power than 2 paralleled EL84.
Cheers,
Ian

[Austin]

http://www2.uiah.fi/~jlummaa/two_stroke/ I almost built this amp when I first started. A book I bought years ago explained how to build it, it is parallel single ended and you can use any tubes you want in it and mix and match for different tones.

Just for trivia Gibson ga-8 are parallel single ended and so are THD bi-valve, but I think that's about the only production ones ones I know of. I always liked the parallel output idea too.

http://my2strokeamp.blogspot.com/
Theres tons of two stroke amp resorces on google

[Chuck H]

A single KT88 will give more power than 2 paralleled EL84.
Cheers,
Ian

AND it's a simpler build!!!

[pdf64]

Weber's Lauren kit https://taweber.powweb.com/store/kits_weber.htm#Lauren should be able to accommodate various tubes / combos, if additional sockets are fitted and the OT secondary tap used is selected appropriately. 10% off currently!

[JoeM]

Assuming that you are set on a Single Ended design then there are better options than paralleling 2 off EL84. The tube (in my own opinion at least) which is closest to the EL84 sonically is not it's big brother the EL34 as most folk might think but rather the KT88. A single KT88 will give more power than 2 paralleled EL84.
Cheers,
Ian

I like that idea too. Bet it would sound nicer than paralleled EL84s.

[loudthud]

One of the problems with parallel SE is finding a suitable output transformer. The Hammond ones are fine at lower power but the impedance is too high to get greater than 10W at low voltage. That knocks out 6V6 and EL84. The big voltage is no problem for 6L6, EL34 or KT88. If you really want to run EL84s, consider two OTs in parallel.

[printer2]

How about these Hammonds? Maybe the 125ESE at 2.5k?

Hammond Mfg. - Universal - Single Ended - Tube Output Transformers - (125 Series)

[tonequester]

How about these Hammonds? Maybe the 125ESE at 2.5k?

Hammond Mfg. - Universal - Single Ended - Tube Output Transformers - (125 Series)

tonequester here.

Thanks to all who replied. I appreciate the advice and the comments equally well. I'll skip around cover it all as best as I can. pdf64, you aren't the first to recommend Weber, and I,m sure they make good kits. however, prior experience with the was enough for me. I waited 3 months for a speaker that I had prepaid for. They ignored many
e-mails, and many phone calls(always got voice-mail that promised a reply). Finally I e-mailed them to advise them that I was involving the Postal Authorities. They e-mailed me with the claim that they had not recieved my coorespondence, which was utter B.S. 3 days after my last e-mail, I received my speaker." Nuff Said." Thanks to gingertube for the KT-88 idea. As Chuck H said..."a simpler build". I always appreciate loudthud and printer2's comments and all of ther info that I glean goes into a "journal"
that I keep.Someday [I]'ll make the final decision. Until then it's "save,save,save", as in cash. Any which way I go will be a major investment. I've got the poverty level beat, but not by much. Before I forget, Pleased to make your "aquaintance" here JoeM !

O.K. Chuck H. In a slightly earlier post you mentioned that perhaps I should give out an example of what I'm trying to accomplish. This is a good idea, so unlike me, I
gave it some considerable thought and referres back to some old notes that I had saved concerning the sound that is my "number one". I don't know if it will help. I already know what equiment was used, and pretty much how. The information comes from the (" horses mouths") via video interviews. First, Leslie West of Mountain. The recording of Mississippi Queen was done at the Fillmore. He played a Gibson Les Paul Junior, with patent number pick-up, controls wide open. Marshall amps he had expected to be there were not. Instead, he used a Sunn 100W. Head (P.A.) through a 2, 4x12 cabs.The guitar's control's were maxed. The Sunn's sungle volume was maxed. He played
the heaviest picks he could find. No effects were used. The cab was miked into the Fillmores P.A system as well. The second example which has the much the same sound
(my opinion), is Cream's recording of Robert Johnson's(pseudo) Crossroads. It was also recorded live at the fiimore. he played a Gibson SG(psychedelic paint) 1963 model
with patent number pick-ups, with a hard-tail bridge. The amplification used was 2 JTM 100,1959 lead models, through 2,4x121 cabs. He played both guitar and amps "cranked up". Clapton also miked into the fillmore West's P.A. system. He can't remember whether he used a Dallas Treble Boost or not. He had used one often
since his Bluesbreakers days. I like the overdriven sound, but not so far as to create more distortion as these examples. Although both amps were push-pull and rated 100 W., they used different tubes, and completely different circuitry. You might ask why I don't get a Gibson. I have, in the past had 2. They got me no closer than I am now. I am going to completely re-wire the Kramer and put a humbucker in the bridge position. I said that this may well be an impossible dream. I am NOT going to buy or build a 100W. anything to keep in the "cranked" mode. Tone is very subjective, and I will get close with a smaller, less expensive amp(barring a hand built kit for the added experience). It may be Class A or Class Q for all I know at present. If tone were the only consideration, I,d save my money and keep my HT-1R "throw-away). However, from experience, I need at leasst 20W., and 30 would be better.

I replaced the nut yesterday, so the acoustic work on the guitar is done. Now I'll re-place all of the circuitry. The only thing left is the amp after that, in maybe 2 months.
I hope the info gives someone an easier time in thinking up something to try, although I doubt that it will. I've played many an amp, some "cranked", and i haven't pleased MY ears yet. Thanks to one and all, you're all great people. Here's all the best to you ALL ! tonequester.

[tubeswell]

I did a SE for 2 x 6V6s a couple of years ago - uses EF86 in V1 with Merlin's triode/pentode morph control, feeding a Big Muff tonestack, 10" greenback, and can run a variety of rectifier tubes (for different B+) - Also has a separate bias resistor for running 1 x 6V6, or a 6L6. Schematic attached.

Soundbyte links FWIW

Me doin' Jimi Page:

Super AC4 - Bigg Muff 3.mp3

Me doin' other stuff

Super AC4 - Big Muff TS.mp3

Super AC4 - Big Muff TS 2.mp3

Super AC4 - Big Muff 4.mp3

[tonequester]

I did a SE for 2 x 6V6s a couple of years ago - uses EF86 in V1 with Merlin's triode/pentode morph control, feeding a Big Muff tonestack, 10" greenback, and can run a variety of rectifier tubes (for different B+) - Also has a separate bias resistor for running 1 x 6V6, or a 6L6. Schematic attached.

Soundbyte links FWIW

Me doin' Jimi Page:

Super AC4 - Bigg Muff 3.mp3

Me doin' other stuff

Super AC4 - Big Muff TS.mp3

Super AC4 - Big Muff TS 2.mp3

Super AC4 - Big Muff 4.mp3

tonequester here.

Thanks for the schematics tubeswell. I've copied everything down for further study(sound links as well). I really appreciate your interest in my post.
If you are Jimi Page fan, you must be a-O.K. in my book. Have a "good 'un". tonequester.

Quote : "If you have a good vibrato, you can get away with a lot". Sonny Terry.

[tonequester]

One of the problems with parallel SE is finding a suitable output transformer. The Hammond ones are fine at lower power but the impedance is too high to get greater than 10W at low voltage. That knocks out 6V6 and EL84. The big voltage is no problem for 6L6, EL34 or KT88. If you really want to run EL84s, consider two OTs in parallel.

tonequester here. A point well taken concerning the transformer. If one finds one, I'm sure that one will pay "through the nose". Thanks for your input, which is always quite welcome
loudthud. Have a "good 'un". tonequester.

Quote ; If a man has common sense, he has all the sense there is". Sam Rayburn.

[Tonewood]

tonequester here.

First, Leslie West of Mountain. The recording of Mississippi Queen was done at the Fillmore. He played a Gibson Les Paul Junior, with patent number pick-up, controls wide open. Marshall amps he had expected to be there were not. Instead, he used a Sunn 100W. Head (P.A.) ...
...I am going to completely re-wire the Kramer and put a humbucker in the bridge position.

Whenever I saw LW back then, he had a JR w/P-90s not Humbuckers, seems like the 90s were a big part of his old sound. Usually looked like this-
" mountain " - live on beat club - YouTube

[tonequester]

Whenever I saw LW back then, he had a JR w/P-90s not Humbuckers, seems like the 90s were a big part of his old sound. Usually looked like this-
" mountain " - live on beat club - YouTube

tonequester here and pleased to "make your aquaintance" Tonewood. Thanks for the great video. The pick-up thing was the sketchiest part of the info that I had gathered.
This video did have a brighter "kick" to it, unlike a humbucker. I wish that I could gotten a good look see. I'm taking your word for it though. The rest of what I posted came from West himself, so I'll stand by it. However, I do wonder at times even about the performer's memory on the subject. George Harrison gave several answers over the years as to what the opening chord from "A Hard Days Night". I have a" note for note" Beatles tab book that claims it to be Fadd9, but my ear says "no Way".
Thanks for the interest and the informational reply, greatly apperciated. tonequester.

Quote ; Knock the "T" out of "Can't". George(Superman)Reeves.

[Chuck H]

It's commonly known that Mississippi Queen is a LP Jr. with P-90's. I can't say if it's commonly correct.

[Austin]

Edcor makes output transformers and power transformers and though I have never ordered from them I read that there are good and also less expensive than Hammond.

I think el84/6bq5 are good place to start because the drive voltage needed for full power is small compared to most tubes so the preamp gain you need is less and could make for a simpler amp because of less gain stages needed. Simple can be good sounding too with less variables to tweak with, and good for learning those variables. As Albert Einstein said; “As Simple As Possible, But Not Simpler,”

Because of the reflected impedance you could build your amp for a four ohm load and drive two 8 ohm speaker cabs or if you wanted less power you could pull one output tube because they are in parallel and only run one speaker cabinet with the same sound, so I think parallel is a cool idea. You may be surprised how loud one single el84 can get with the right speaker and it would be good in my opinion to have an option of reduced volume and still retain the sweet tone of a cranked up amp.

[tonequester]

tonequester here.

Hey Austin ! I'm kind of slow to reply sometimes, but I surely wanted to thank you for the "two stroke" leads. The parallel/single ended thing is where I'm 99% sure that I'm heading for. I really appreciate your replies. I have the feeling that there is good tone to be found "down by the river". It's "funny", we joined the forum at about the same time, but
you've given me a lot, and all I can do dor you is to say "thanks, from the bottom of my heart". tonequester out.

[tonequester]

It's commonly known that Mississippi Queen is a LP Jr. with P-90's. I can't say if it's commonly correct.

tonequester here.


Hey Chuck. I know that you are NOT yankin' me this time. After checking my sources, I must submit to the majority(too bad it don't work that way with
the government). If I were having this conversation with one of our elected, I could probably buy a change in historical fact ! Everything I said EXCEPT the type of pick-up was correct as near as I can tell from the interviews of West in print and on "video". Me being Me, guarantees at least one major slip(crash). I try to learn from my mistakes
because that is the greatest volume of work that I possess. I now believe that he used the Alnico 5 models. I'll probably find tomorrow that they were in fact Alnico 2.
I'd get me a "Junior" in a heartbeat, but I don't think that I could get my hand around it. Perhaps my biggest curse, as to playing, is small hands. Have you ever noticed the hands that guys like West, Stevie Ray Vaughn, and Chuck Berry have/had ? Some have big hands, and some have big..................Feet ? Have good rockin' tonight !
tonequester.

Another "down on the farm" Quote : "You got to have smelt a lot of mule manure before you can sing like a hillbilly". Hank Williams sr.

[tonequester]

tonequester here.



Hey Austin. Thanks for the reply. I haven't even gotten around to figuring out what i wanted to do with the speaker situation yet, but I like your idea on the 4 Ohm load build, into 2x8 Ohm cabs. I'm also "stoked' about your feelings on the possible perceived loudness of one EL-84 output tube. I plan to include the option to turn down, for sure.
I've heard of Edcor transformers, but haven't any experience with them. Unfortunately, the kit I'm considering comes with a Hammond, but the price is the lowest I've found yet.
Thanks for your reply. I always am pleased to hear from you, as you aren't afraid to think "out of the conventional box'. Have a great one ! tonequester.

[olddawg]

I played old DC LP Juniors, Specials, Melodymakers for years. I have smallish hands. The early 60s neck profiles were slim. That's why a lot of chicks play MMs. Anyway, after reading your description of the sound you are trying to achieve in a low wattage amp, I would recommend building a Marshall 18 watt or a Vox 18 watt variant. Hit one with an OD pedal and you will be there through a 4x10 or 4x12 cab. I have an 18 watt clone built into a generic Marshall head box and run it through a 1965A cab. It sounds great dimed at club levels and looks like the real deal on stage without blowing out eardrums.

[Amp Kat]

Call Paul at Mercury Magnetics and get one of the FTPO series SE trannys. He will prolly cut you a deal and they are very nice sounding and really not that more expensive. Paul will help you with the specs and he's a pretty cool dude.