Where best to post about diff between Fender and Dumble?

[imo1]

What’s the signal path in the clips ? Pedals?

The Hendrix clip is straight in. The blusier one is half of a duelist(heavy hand) with gain on maybe 1, and level and tone basically at noon

[imo1]

The .001 treble cap into the mid switch(off) has 280pF into the treble pot. These seems pretty insignificant looking on the tone stack chart.

Agreed.

If you are going this far down that rabbit hole searching for your sound then what’s negligible becomes easily arguable . Nuances remain

Recorded on an iphone, but you can hear the gist of it. To me, you can really hear an important part of what Ive been looking for at 15 seconds in. There is that overtone(on the BB king lick) that makes those notes come alive. Blues riff.m4a

Also attaching a cleaner take. This one suffers from some iphone distortion, so it doesn't do the amp justice. the is harmonic distortion, but no gainy distortion. This is around what I would call a "clean sound" and I love how the chords and low end hold together, lots of definition when I play the low E, but it has that very pleasing sound where nothing pokes out. Before, when i would play some of these big chordal parts, I would find myself using compression to reign in the frequencies. Angel.m4a

Sounds decent , got any gut shots for reference ?

Took these quickly. I don’t know what you are looking for, but shows general layout and then the switches on front panel

IMG_2086.jpeg

IMG_2085.jpeg

[WhopperPlate]

Agreed.

If you are going this far down that rabbit hole searching for your sound then what’s negligible becomes easily arguable . Nuances remain

Recorded on an iphone, but you can hear the gist of it. To me, you can really hear an important part of what Ive been looking for at 15 seconds in. There is that overtone(on the BB king lick) that makes those notes come alive. Blues riff.m4a

Also attaching a cleaner take. This one suffers from some iphone distortion, so it doesn't do the amp justice. the is harmonic distortion, but no gainy distortion. This is around what I would call a "clean sound" and I love how the chords and low end hold together, lots of definition when I play the low E, but it has that very pleasing sound where nothing pokes out. Before, when i would play some of these big chordal parts, I would find myself using compression to reign in the frequencies. Angel.m4a

Sounds decent , got any gut shots for reference ?

Took these quickly. I don’t know what you are looking for

Too much to detail

, but shows general layout and then the switches on front panelIMG_2086.jpegIMG_2085.jpeg

I asked my wife what she thought of your clips (my resident critical ear ). She said the low mids were full and nice , but it’s a little bit toothy at the top end .

Looking at your board I see a ton of 715p caps , and that would make sense that you have had to temper the spikiness of the amplifier via other component value changes . If I were you I would highly consider a few 6ps alternatively , even just a pair in the PI or one off v1b might yield results to your liking .

Fender used polyester caps , not polypropylene, so if you like the fender character that’s definitely something to consider . Not exactly subtle, you may not hear much fine tuning that treble cap by a few picofarads , but I betcha money you will hear that cap swap .

Edit: I also see those f&t caps on the mains that can give a grainy shrill ,( spiky even) character to the sonic footprint if not careful . Mentioned in another recent thread here . Just one more place for fihe tuning should you end up needing .

[martin manning]

;^)

[imo1]

If you are going this far down that rabbit hole searching for your sound then what’s negligible becomes easily arguable . Nuances remain



Sounds decent , got any gut shots for reference ?

Took these quickly. I don’t know what you are looking for

Too much to detail

, but shows general layout and then the switches on front panelIMG_2086.jpegIMG_2085.jpeg

I asked my wife what she thought of your clips (my resident critical ear ). She said the low mids were full and nice , but it’s a little bit toothy at the top end .

Looking at your board I see a ton of 715p caps , and that would make sense that you have had to temper the spikiness of the amplifier via other component value changes . If I were you I would highly consider a few 6ps alternatively , even just a pair in the PI or one off v1b might yield results to your liking .

Fender used polyester caps , not polypropylene, so if you like the fender character that’s definitely something to consider . Not exactly subtle, you may not hear much fine tuning that treble cap by a few picofarads , but I betcha money you will hear that cap swap .

Edit: I also see those f&t caps on the mains that can give a grainy shrill ,( spiky even) character to the sonic footprint if not careful . Mentioned in another recent thread here . Just one more place for fihe tuning should you end up needing .

I love that you can get your wife to weigh in on guitar tones! I'm pretty sure my wife spells "guitar", "kitar'

I actually am digging the "toothiness" on the top end. I could dial that out by flattening the presence. To me, that is at the core of Stevie's sound and that edge is something I like. As i said, I'm gonna have to play it for a while to see what shakes out in different environments.

I'm flying down to Austin next week. I'm gonna take some 15u caps with me and, if I have time, try them in my 50w. I'm curious to see how much difference there is with the wattage difference in terms of low end reactance. My assumption is that I might have to split the difference, or leave the 5u cathodes as they are. We will see

[WhopperPlate]

IMG_4748.jpeg

;^)

I live in a rabbit hole… just gotta remember how to get back to Albuquerque …

[WhopperPlate]

I love that you can get your wife to weigh in on guitar tones! I'm pretty sure my wife spells "guitar", "kitar'

All I have to do is turn it up at all and she will react one way or another:

“What’s that horrible sound?”… *closes door to shop

*opens door to shop …“What’s that nice sound?”

[WhopperPlate]

I actually am digging the "toothiness" on the top end. I could dial that out by flattening the presence. To me, that is at the core of Stevie's sound and that edge is something I like. As i said, I'm gonna have to play it for a while to see what shakes out in different environments.

The live gig will tell you everything about whether or not it cuts your mustard . You know what to swap if you want a change .

[stratomaster]

Hey Ian. Big fan of your work, and always dug the tones you got with your Super back in the 90s--and the vocals, especially on your more gospel type tunes, are inspired and inspiring.

An idea popped into my head as I read through this thread. You mentioned liking some aspects of the Two Rock/Dumble tonestack and wished you could blend some Fender attributes back in. If you have a spare Black/Silver Fender Reverb amp you can do exactly this. Modify one channel to have the Dumble tonestack, cathode caps and LNFB. Split the cathodes for the second stage with some tag strips to get the full dedicated preamps. Then mix the channels internally just before the reverb send.

Now you have a Dumble preamp channel, a Fender preamp channel, and a familiar phase inverter and power amp section. Best yet, both channels are now in phase and have reverb/trem available. You can run a patch cable from input 2 on one channel to input 1 on the other. You can blend and EQ as you'd like. A Twin Reverb would be the obvious choice to have 3 band EQ for both channels.

Alternatively, focusing back on your amp builds-- one place I haven't seen you mention experimenting is the value of the screen resistors on the power tubes. I find 1k gives me less "clack" than the traditional 470ohm, and has the benefit of slightly taming the power. It's almost like the compression effect of turning the amp up, but it comes on sooner in the volume range. Experiment with up to 2.2k here. If you're having to use attenuators this will help with tube longevity as well.

Finally, to increase low mid punch while keeping the bass under control I like to use 2.2 -3.3μF cathode caps on V1a, decrease the slope resistor to 82k, and decrease the mid cap to 0.022μF. This shelves the low end at the very beginning of the amp, tightening it like a tube screamer would, without the added mids. It also increases the low mids very substantially and shifts the point at which the scoop occurs. Think of your Super Reverb and imagine if it could hold the low end together just a notch or two higher on your volume--and you can turn the bass past 3 without the tone folding in on itself. It sounds counterintuitive to voice it like this, but it really works in my Blackface Reverb amps with single coils. Especially if you've disconnected the vibrato pot for more punch.

Edit
Almost forgot: if you do decide to do the Dumble/Fender mod on a Fender amp, it could be helpful to add LNFB to V4b to keep the preamp section in check.