1. #1

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    this one has been developing in my head and ears for some time. I have the good fortune to have cool relationships with Eddie Wang https://www.eddiewanginstruments.com and Bryan Sours https://soursound.com and to consider Jef Brown a long-time friend and sonic guide.

    the idea was to create a low watt amp....with high headroom and very simple design. I wanted as small a footprint as possible - but a box big enuf to handle a 12" or 15".

    I have long dug the tone of an EF86 and for yrs used EL84's. I imagined possibly going to a 'big bottle' single power tube....but we quickly scrapped that idea and ended up back with my affinity for EL84's and with Eddie's guidance....a pair of them.

    Eddie had me over to his shop and we A/B'd a number of circuit options and he took careful notes as he let my hands and ears guide me along the sonic path that most appeals to me.

    We decided on a pine cab.....it will be about the size of a Tweed Deluxe for reference. all finger joined and rings like an instrument. the front frame of the amp is joined to all mating surfaces. this was Eddie's discovery after playing around with cab designs.

    it will have about a 2-3 degree tilt.... again a dimension Eddie recommended after experimentation. the amp controls will be rear/top mount just like an old Tweed Fender. made it possible to shrink the overall size of the cab.

    a classy tolex was applied and grille cloth will be reminiscent of those old console stereo speaker covers.....some gold thread running thru it. have yet to decide on handle.....got to be functional and aesthetically pleasing.








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  3. #2

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    Mmm ... tubes! Now we're talkin'! What kind of "vibe" are you shooting for -- is this a "jazz" amp, versatile, or what?

    Please keep us posted!

    Marc

  4. #3
    spent a few hours with Eddie running thru 3 different OT from Bryan's bench. we landed on one that is somewhere between and Tweed and Deluxe Reverb.

    been spending time tube rolling and then checkin out speakers.

    at this point I have settled on a 12ax7 in V1 feeding the EF86 in V2. started with a 12ay7 in V1 which gives the amp a more Tweed-like feel. nothing wrong with it but the EF86 and my ears preferred the ax7.

    going with a GZ34 rectifier, thought a 5Y3S was a worthy choice.

    have run thru 3 speaker choices....all from Amperian..... settled on a Nobels 65 (alnico 12" 8ohm 65 watt) for now. going to check out another ceramic that may be a great middle ground.

    so far....wow.

    plan is to get this one done....(as done as prototypes ever are) and then have a series of local guitar players put it thru the paces.

    then we will build a limited run of 4 - for public consumption.

  5. #4
    Quote Originally Posted by marcwhy
    Mmm ... tubes! Now we're talkin'! What kind of "vibe" are you shooting for -- is this a "jazz" amp, versatile, or what?

    Please keep us posted!

    Marc
    hey man....cool to hear from ya.

    well....I wanted something really simple...no verb....no tremolo....that had gobs of headroom and a lot of clarity.

    Eddie nailed it and this thing is far more versatile than I imagined.

    he has a Voltage Regulator circuit he uses in all of his builds. I was unsure about it as many of them choke the life out of amps I have played. he was able to describe the technical approach to his design in a way I could understand. we went for it....and I am so glad we did.

    the influence and interplay of the Volume and Voltage controls is kind of where its at in this amp.

    you can play nearly as clean as you want and pretty loud...louder than I would gig with it....or twist the knobs and you can get it dirty and nasty.

    the real star is the Voltage regulator. it brings to life the EQ section and controls of the amp. as you increase Voltage...the Bottom and Top controls increase in their interplay and effect....so you can make it a rich sounding amp or a bright and sparkly one.
    Last edited by scotteave; 09-20-2021 at 10:12 PM.

  6. #5

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    Sounds like a lot of fun!

    [This may be blasphemy for some, but I think amps can be funner than guitars!]

  7. #6
    Quote Originally Posted by marcwhy
    Sounds like a lot of fun!

    [This may be blasphemy for some, but I think amps can be funner than guitars!]
    yeah....they make a pronounced impact on the signal chain....that is for sure.

    some would argue....you need to work from the amp back to your fingers when finding your tone....

    of course we could simplify all of this and just play acoustic......

  8. #7

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    Um, just how does a voltage regulator accomplish this:?

    the real star is the Voltage regulator. it bringing to life the EQ section and controls of the amp. as you increase Voltage...the Bottom and Top controls increase in their interplay and effect....

    Just sayin by definition a voltage regulator maintains a constant voltage. So the increases you speak of are interesting, considering a VR doing its job is not allowing fluctuations.

  9. #8
    hey jazzkritter....great questions....

    I have word out to Eddie to get some input from him...... will post as soon as I hear back.

    thx

    Scott

  10. #9
    Voltage Regulator

    this is from Eddie Wang the designer and builder of the amp. you can find him here as well. EDDIE WANG INSTRUMENTS - Home

    Hmmm... kinda complicated... but in short, it's main purpose is to control the wattage of the amp. It regulates the voltage POST rectifier tube (so all the heaters for the tubes all operate at their ideal voltage), and adjusts the voltages the tubes see proportionally... so the tubes "think" they're still operating normally. It's like installing lower voltage rectifier tubes as you turn it down.

    When recording, the differences between the voltage set higher or lower are pretty minimal. In person, there's the psychoacoustic element - with louder sounds, our ears (and minds) are more sensitive to highs and lows. This may explain the sensation that it's more complex. Although there is something to that - louder means the speakers also break up more and add to the overall sound.

    hope that helps and if more info / insights needed....happy to oblige.

    it is complicated - one of those things where
    experiencing it really helps with understanding the effect.