EVH tone deep dive feat. DAVE FRIEDMAN and PETE THORN

I'm seriously missing the boat on these classic tones. Had EVH had recorded Eruption on a stock amp, would anyone have said "if only he modded the flux capacitor and put in tubes made by Keebler elves in hollowed out trees, this may have been a good track"?
It's not the tone. It's those songs. For god sakes the iconic guitar was a Partscaster. Much respect for EVH and the contribution, but IMO all this tone chasing is misguided and overly read into. Dave Friedman is in the business of selling amps and pedals, so take it all with a grain of salt. You too can plug into a stock DSL and take over the world with a guitar. No mojo/mystery mods or any other hocus pocus necessary.
 
I'm seriously missing the boat on these classic tones. Had EVH had recorded Eruption on a stock amp, would anyone have said "if only he modded the flux capacitor and put in tubes made by Keebler elves in hollowed out trees, this may have been a good track"?
It's not the tone. It's those songs. For god sakes the iconic guitar was a Partscaster. Much respect for EVH and the contribution, but IMO all this tone chasing is misguided and overly read into. Dave Friedman is in the business of selling amps and pedals, so take it all with a grain of salt. You too can plug into a stock DSL and take over the world with a guitar. No mojo/mystery mods or any other hocus pocus necessary.

Yes, the logical step would be to come up with a production line of that amp. It would sell like crazy!

However, they did a fantastic job and proved that they both know how to recreate, that tone and I would like to do that in my Axe-Fx as well.
Sure, it's not for everybody, but if I accept that, then it raises the question of why even prefect the AF more when it should be good enough already.

I barely play any other amp in the AF than the Plexi. Maybe I should just get an overprice real one, modded by Dave :D
 
I'm seriously missing the boat on these classic tones. Had EVH had recorded Eruption on a stock amp, would anyone have said "if only he modded the flux capacitor and put in tubes made by Keebler elves in hollowed out trees, this may have been a good track"?
It's not the tone. It's those songs. For god sakes the iconic guitar was a Partscaster. Much respect for EVH and the contribution, but IMO all this tone chasing is misguided and overly read into. Dave Friedman is in the business of selling amps and pedals, so take it all with a grain of salt. You too can plug into a stock DSL and take over the world with a guitar. No mojo/mystery mods or any other hocus pocus necessary.

I get what you're saying, but I believe it also has to do with how it came out of left field at the time. Up until then, that tone and style was unheard of in the truest form of the definition. He pioneered and opened up a whole new way of playing and tone. I've been playing 25+ years and have my own style and tone, but I still love to try to emulate Dimebag's tone, as horrendous as it was, because it brings back memories of youth and a passion. I'd wager the same thing is going on here. :)
 
I wouldn't say it came out of left field that much. From the early 60's on people were searching for more and more gain and sustain and were experimenting with all kinds of setups. Many of EVH's licks and show off style were partly a continuation and extension of other flamboyant lead guitarists like Hendrix. EVH was definitely an amazingly talented musician and extremely influential for those that followed, but it's not like everyone else was playing smooth jazz at the time. Heavy blues guitar based rock music was alive and well with bands like Led Zeppelin, Thin Lizzy, Blue Oyster Cult, Black Sabbath, Boston, Deep Purple, and many more. EVH did take things a step further and his technical prowess was impressive, but he was still very much a product of his time and place.
 
I'm seriously missing the boat on these classic tones. Had EVH had recorded Eruption on a stock amp, would anyone have said "if only he modded the flux capacitor and put in tubes made by Keebler elves in hollowed out trees, this may have been a good track"?
It's not the tone. It's those songs. For god sakes the iconic guitar was a Partscaster. Much respect for EVH and the contribution, but IMO all this tone chasing is misguided and overly read into. Dave Friedman is in the business of selling amps and pedals, so take it all with a grain of salt. You too can plug into a stock DSL and take over the world with a guitar. No mojo/mystery mods or any other hocus pocus necessary.
I agree, kinda, but you have to admit, the sound IS cool, and adds to the way cool vibe.

Not to mention how do you get from your stated viewpoint to owning an Axe III? ;)
 
I agree, kinda, but you have to admit, the sound IS cool, and adds to the way cool vibe.

Not to mention how do you get from your stated viewpoint to owning an Axe III? ;)
I like a variety of tones, but when the AXEFXIII created the authentic tab it was like a gift from god. Im not an endless tweaker. Pull up an amp or effect, pepper to taste and go. The brown sound is like obsessing over an old muscle car. Compared to todays engineering, they're awful. Same with this. Get any NEW premium amp, pick one. Mezzabarba, Friedman or anything of that caliber. You have tone for miles and don't have to worry about tracking down tubes or other parts sourced from an old Mir space station. EVH did what he did as did the other greats from the era. They worked with what they had at the time. Thats cool and all from a historical point of view, but personally I'd rather watch paint dry than watch a video of an influencer and a builder discussing the finer points of 50 year old tech. I completely understand I do not live in a bubble and maybe others do, and thats cool too. Different strokes and all.
 
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Some relevant info:
1. Changing the mid pot to 50K doesn't do much. If the Mid pot is at maximum then it adds about 2 dB boost at 600 Hz.

2. You can replicate the variac using the Variac control. Set it to around 0.8.

3. The various Plexi models have different default feedback configurations as follows:
Plexi 50W: 100K from 4-ohm tap.
1987x: 100K from 8-ohm tap
Plexi 100W: 47K from 8-ohm tap
1959SLP: 47K from 8-ohm tap
Plexi 6550: 100K off 4-ohm tap
Plexi 100W 1970: 100K off 4-ohm tap
Plexi 50W 6CA7: 100K off 4-ohm tap

If you want to recreate 47K from the 4-ohm tap with the Plexi 100W model you would reduce Negative Feedback by 1/sqrt(2) = 0.71. The default value is 6.6 so the new value would be 4.7.

If you want to replicate changing the resistor value you scale by the ratio of the old value to the new value. I.e. if the original value is 100K and you want to simulate 47K you would double the negative feedback.

Note that this isn't exact as changing the feedback resistor also changes the impedance "seen" by the phase inverter but it will get you in the ballpark.

4. The "Fat" switch on V2 is a capacitor across the 820 ohm cathode resistor. Some Plexis had no cathode cap. Others had 0.68uF.

The "Voice" switch on a Friedman BE switches in a 470uF cap in one position.

There is no way to replicate changing the cathode cap in the models. I'm personally not a fan of large cathode caps on V2. I think it makes the tone to mushy.
 
3. The various Plexi models have different default feedback configurations as follows:
Plexi 50W: 100K from 4-ohm tap.
1987x: 100K from 8-ohm tap
Plexi 100W: 47K from 8-ohm tap
1959SLP: 47K from 8-ohm tap
Plexi 6550: 100K off 4-ohm tap
Plexi 100W 1970: 100K off 4-ohm tap
Plexi 50W 6CA7: 100K off 4-ohm tap
Regarding this, what effect has changing the tap of the negative feedback?
I recently bought a Hiwatt Little D head which is basically a 20W version of the old Hiwatt DR504, it is pretty much identical except for the fact it uses EL84s in place of EL34s.
One of the few differences I noticed by checking the innards is the presence circuit connected to the 8-ohm tap, while in the original DR504 it is connected to the 16-ohm tap.
Eventually can I just move the wire to the 16-ohm tap without other modifications?
 
The higher impedance taps will have higher output voltages, giving more negative feedback compared to the lower ones. In general, more negative feedback = cleaner and more punchy power amp and less negative feedback = dirtier and more compressed power amp. You can also disconnect it completely for no negative feedback for an even more power amp breakup. For example, Vox AC30 and Fender Tweed Deluxe amps have no negative feedback. Contributes to their ease of break up when cranked.
 
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The higher impedance taps will have higher output voltages, giving more negative feedback compared to the lower ones. In general, more negative feedback = cleaner and more punchy power amp and less negative feedback = dirtier and more compressed power amp. You can also disconnect it completely for no negative feedback for an even more power amp breakup. For example, Vox AC30 and Fender Tweed Deluxe amps have no negative feedback. Contributes to their ease of break up when cranked.
Yep, I just read a bit about it and found the same info.
So I can put it on the 16-ohm tap with no issue and, actually, to achieve the same amount of negative feedback as the 50W I could also lower the resistor value a bit since a 20W amp surely spits out a lower voltage.
 
as Pete said in the video when he was dialing in some curves on the GE10, any boosted EQ curve is probably gonna have more of an impact on the tone than small tonal changes like tubes or the mid pot.

I believe the core of that tone really lies in the dimed Plexi, the Variac and possibly the lower Negative Feedback (amp-wise at least). that's what gets you the character and feel. fortunately we've got those parameters already available to tweak...

2dB mids at 600hz more or less really becomes insignificant at that point.
having said that, eventhough Cliff calls it mushy, I'd still love to have that "Fat Cap" option ;) ...
 
Yep, I just read a bit about it and found the same info.
So I can put it on the 16-ohm tap with no issue and, actually, to achieve the same amount of negative feedback as the 50W I could also lower the resistor value a bit since a 20W amp surely spits out a lower voltage.
You may find that the value/tap chosen at the factory were chosen to give a similar response to the larger one. The output tubes being EL84 instead of EL34 makes a bit of difference in the needed amount of feedback, due to their different grid sensitivity and drive requirements....
 
You may find that the value/tap chosen at the factory were chosen to give a similar response to the larger one. The output tubes being EL84 instead of EL34 makes a bit of difference in the needed amount of feedback, due to their different grid sensitivity and drive requirements....
Actually it has the same exact resistors configuration as the bigger amps: 10k and 470R to ground.
I already made the calculations based on what is said on this link and, to have roughly the same feedback voltage of a 50W, I need to use the 16-ohm tap and replace the 10k resistor with a 6.2k one.
Sure, maybe el84s don't need all that negative feedback, but trying is a little effort and it is reversible. :)

Anyway, I think who designed this amp really had no clue about what he was doing and I have no trust at all, I already had to fix two big mistakes the first day I got it.
One was a nonsense wiring of the input jacks, basically each input was shunting to ground thru the grid stopper of the unused input, so I had an input impedance of 68k instead of 1M. Had to redo the wiring.
The other was the pilot lamp pins (where there is 230V AC!) almost touching a turret, and that was causing an unbearable noise when turning up the master. Had to remove the lamp (now it's dead silent) and I'm waiting for a shorter replacement, or in alternative I'll power it thru the heaters supply (6.3V DC).
Here's the evidence of the crime:

IMG_20201120_143850.jpg

The next thing I'll check is if they biased the el84s properly, I hope they didn't use the same 450V plate voltage as the 50W...

And I also hope the new owners of the company don't make these silly mistakes anymore
 
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The other was the pilot lamp pins (where there is 230V AC!) almost touching a turret, and that was causing an unbearable noise when turning up the master.
Jeez. 😳

Well, it's an easy swap, as you said, and as you demonstrated, the builder may not be the sharpest marble in the sack, so good luck!
 
Some relevant info:
1. Changing the mid pot to 50K doesn't do much. If the Mid pot is at maximum then it adds about 2 dB boost at 600 Hz.

2. You can replicate the variac using the Variac control. Set it to around 0.8.

3. The various Plexi models have different default feedback configurations as follows:
Plexi 50W: 100K from 4-ohm tap.
1987x: 100K from 8-ohm tap
Plexi 100W: 47K from 8-ohm tap
1959SLP: 47K from 8-ohm tap
Plexi 6550: 100K off 4-ohm tap
Plexi 100W 1970: 100K off 4-ohm tap
Plexi 50W 6CA7: 100K off 4-ohm tap

If you want to recreate 47K from the 4-ohm tap with the Plexi 100W model you would reduce Negative Feedback by 1/sqrt(2) = 0.71. The default value is 6.6 so the new value would be 4.7.

If you want to replicate changing the resistor value you scale by the ratio of the old value to the new value. I.e. if the original value is 100K and you want to simulate 47K you would double the negative feedback.

Note that this isn't exact as changing the feedback resistor also changes the impedance "seen" by the phase inverter but it will get you in the ballpark.

4. The "Fat" switch on V2 is a capacitor across the 820 ohm cathode resistor. Some Plexis had no cathode cap. Others had 0.68uF.

The "Voice" switch on a Friedman BE switches in a 470uF cap in one position.

There is no way to replicate changing the cathode cap in the models. I'm personally not a fan of large cathode caps on V2. I think it makes the tone to mushy.

With the variac turned down, is there anything we need to do to “rebias” at the new voltage?
 
Jeez. 😳

Well, it's an easy swap, as you said, and as you demonstrated, the builder may not be the sharpest marble in the sack, so good luck!
Thanks!

Actually I just finished trying the 16-ohm tap and I liked it lot, I gained a good amount of headroom and a lot of fizzyness I had with the master cranked went away. Next step is reducing the feedback resistor, I'm quite confident I'll like it even more.
 
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