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Topic: Milk Man Mini PSA |
Paul Sutherland
From:
Placerville, California
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Posted 25 May 2022 5:27 pm |
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Try swapping out the solid state rectifier for a tube rectifier. I just did and I'm loving it.
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It don't mean a thing if it ain't got that swing. |
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Jim Robbins
From:
Ontario, Canada
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Posted 25 May 2022 7:25 pm
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| Yeah, I had Tim put in a tube rectifier from the get go. Fantastic sounding amp. |
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Tal Herbsman
From:
Wisconsin, USA
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Posted 27 May 2022 6:37 am
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| Me too! One of the advantages of replacing the SS rectifier is that it is a little less loud which is perfect for my needs. |
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b0b
From:
Cloverdale, CA, USA
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Posted 27 May 2022 7:45 am
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My Mesa/Boogie has a switch on the back "Vintage/Bold" that switches rectifiers. I always preferred the solid state rectifier for pedal steel because it gives a little more headroom and doesn't sag on a strong attack. I haven't thought about it recently, though. I used that amp with a lap steel at a jam last night, and now I'm reconsidering my choice. Thanks for jogging my memory.
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-𝕓𝕆𝕓- (admin) - Robert P. Lee - Recordings - Breathe - D6th - Video |
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Paul Sutherland
From:
Placerville, California
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Posted 27 May 2022 7:07 pm
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I looked at the tube complement on various Little Walter amps and all that I saw had a rectifier tube. Of course, they also had octal preamp tubes. Perhaps a tube driven rectifier is at least part of the tone so many are seeking.
_________________
It don't mean a thing if it ain't got that swing. |
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b0b
From:
Cloverdale, CA, USA
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Posted 27 May 2022 9:57 pm
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| Paul Sutherland wrote: |
| I looked at the tube complement on various Little Walter amps and all that I saw had a rectifier tube. Of course, they also had octal preamp tubes. Perhaps a tube driven rectifier is at least part of the tone so many are seeking. |
I don't see how the rectifier can effect tone. The differences I notice are in the attack envelope and headroom. As I understand it, the rectifier isn't in the signal path, but it affects the ready availability of power to the tubes. The tube is slower to respond than a solid state diode bridge. (I might be wrong about that - I'm not an electrical engineer.)
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-𝕓𝕆𝕓- (admin) - Robert P. Lee - Recordings - Breathe - D6th - Video |
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Donny Hinson
From:
Glen Burnie, Md. U.S.A.
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Posted 11 Jun 2022 6:38 am
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| b0b, short answer is that it can affect the tone, somewhat, because as the B+ (and B-) voltages change throughout the circuit, the linearity of the frequency response changes. These are really tiny changes, to be sure, but they're apparently important to some players. |
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b0b
From:
Cloverdale, CA, USA
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Dave Mudgett
From:
Central Pennsylvania and Gallatin, Tennessee
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Posted 13 Jun 2022 12:56 am
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I think the biggest impact of solid-state vs. tube rectification occurs when the amp is pushed pretty hard. Like beyond the design rating of the amp.
For a lot of guitar players, the primary use case is pushing the amp way beyond the limits of what the designers had in mind. Amp pretty much cranked, and additional gain (sometimes a lot), distortion, and other effects in front of the amp. At this point, I think the voltage sag can have a huge impact on the overall sound. And different rectifiers have different current capacities, and produce more or less B+ voltage/current sag when pushed.
But I don't think it is necessary to push the hell out of an amp to notice the difference between a SS rectifier and anything but a real stout tube rectifier like a GZ-34/5AR4. For example, a lot of older, mid-powered Fender tube amps like the Deluxe, Vibrolux, Super, and Pro Reverbs came with either 5AR4 or 5U4 rectifiers, at various times in production. Unless I was going for a real tight guitar sound, I generally thought that the 5U4 sounded noticeably sweeter when pushed moderately with a guitar. For blues or rock and roll, I have almost always preferred the 5U4. Of course, most pedal steel players prefer more headroom. And if the extra clean volume is needed, going to the heavier rectifier makes sense. But I think some sweetness is lost when pushed.
I see this as follows - power tubes do have a somewhat more gradual saturation response vs. volume than typical bipolar transistors. And the transformer can saturate some too. But I think even most power tubes saturate fairly sharply on their own, given an unlimited B+ supply. The response will stay pretty linear and then cutoff fairly quickly - this can be verified on a scope with a test circuit and a signal generator. But the voltage sag from a not-so-stout rectifier (which can be measured) can start pretty early and make that saturation start earlier and more gradually kick in. That's what I hear with a lower-capacity rectifier. I've used tons of mid-power Fenders and that has always been my conclusion.
As an example, I think that the saturation response of, let's say, a Twin Reverb being pushed is qualitatively different than, let's say, a Deluxe or Super Reverb. Of course, one must take into account the differences in overall volume. But I think there's a reason, beyond sheer volume (which is frequently a no-no on stage) why Twin Reverbs have lost popularity among guitar players relative to their smaller brothers. Yes, the smaller amps are not as loud and compress/distort at lower volumes. But I think the character of the compression/distortion is also different, and I think a signficant chunk of that is the tube vs. solid-state rectification. |
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