I'm trying to make Friedman Dirty Shirley.
To be precise, I am thinking of making a Twin Sister.
(Perhaps it is a structure that switches the 1st and 2nd stage and the tone stack in Dirty Shirley)
One concern is the rectifier.
Dirty Shirley / Twin Sister has tube rectifier.
I haven't used a rectifier tube at my own made amp yet.
I didn't like it because the power transformer had to be large and the wiring was complicated.
Since the Dirty Shirley uses a rectifier tube, I searched the difference between a tube rectifier and a solid rectifier.
Since the response of the tube is slower than that of the solid, sag occurs when a strong signal is input, and there is a spongy touch overall.
Solid has a quicker response than a tube and has an accurate feel.
It was all about the content that I searched.
However, it was said that a high-capacity rectifier tube such as the GZ34 had less such characteristics.
Unlike the non-master volume amplifiers, JCM800-like amplifiers like Dirty Shirley don't seem to overdrive the output tube very much.
I am curious to see if the tube rectifier exhibits its unique characteristics compared to solid even in this type of amplifier.
Please answer on the premise that the voltage after rectification is the same.
This is because if the rectifier type is decided, the appropriate transformer will be ordered.
Tube rectifier vs solid rectifier in Preamp gain type amplifier
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psychepool
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Re: Tube rectifier vs solid rectifier in Preamp gain type amplifier
Simply go with diodes. To sag a tube rectifier you need variable current demand, and on a preamp you haven't any.
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Stevem
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Re: Tube rectifier vs solid rectifier in Preamp gain type amplifier
If you go with SS diodes use the fast recovery type as they are nearly as quiet as a tube recto, but for the cost of them I find it still pays to bypass them with a ceramic cap.
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Re: Tube rectifier vs solid rectifier in Preamp gain type amplifier
The comments are correct: preamps don't have enough change in current to make sag an issue; and using fast recovery FREDs (Fast Recovery Epitaxial Diodes) can make for significantly less diode commutation noise, although preamps mostly don't have enough current needs to make this an issue.
Another consideration is that the difference between solid state diodes with a series resistor added and tube rectifiers is very small indeed. Tube rectifiers can be very, very closely approximated by solid state diodes with a series resistor. Although die-hard tube fanatics refuse to believe it, SS diode and resistor combinations are difficult if not impossible to tell apart by ear, according to many people who report actually trying it.
Accordingly, you can assume you are using a tube rectifier, and use EITHER a tube or SS diodes and a resistor.
Another consideration is that the difference between solid state diodes with a series resistor added and tube rectifiers is very small indeed. Tube rectifiers can be very, very closely approximated by solid state diodes with a series resistor. Although die-hard tube fanatics refuse to believe it, SS diode and resistor combinations are difficult if not impossible to tell apart by ear, according to many people who report actually trying it.
Accordingly, you can assume you are using a tube rectifier, and use EITHER a tube or SS diodes and a resistor.
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thetragichero
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Re: Tube rectifier vs solid rectifier in Preamp gain type amplifier
if i may, i believe op is building a full amp (pre- and power so), but was referring to amps that get their distortion primarily from the preamp (like a jcm800) rather than the power amp (like a jtm)
that being said i almost always use diodes even when the transformer has a 5v heater tap. little-to-no benefit to using a tube rectifier (with inline diodes in the event it shorts) over just diodes
that being said i almost always use diodes even when the transformer has a 5v heater tap. little-to-no benefit to using a tube rectifier (with inline diodes in the event it shorts) over just diodes
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Re: Tube rectifier vs solid rectifier in Preamp gain type amplifier
I consider the slow ramp up of the HT provided by a GZ34 to be a significant benefit, as it all but eliminates power up surge current in that circuit, hence allowing a quick blow HT fuse to be used.
Dunno if I’ve ever been aware of rectifier switching noise from silicon diodes, but the complete elimination of any potential for that is one less thing to worry about.
But if the wiring up of a tube rectifier is a too much of a worry (additional wire count of 2 or 3 compared to silicon), then a building an amp with a high gain preamp would seem to be off the scale
Dunno if I’ve ever been aware of rectifier switching noise from silicon diodes, but the complete elimination of any potential for that is one less thing to worry about.
But if the wiring up of a tube rectifier is a too much of a worry (additional wire count of 2 or 3 compared to silicon), then a building an amp with a high gain preamp would seem to be off the scale
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psychepool
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Re: Tube rectifier vs solid rectifier in Preamp gain type amplifier
From the answers, it seems reasonable to use a diode rectifier.
There seems to be a little confusion because of the text "preamp gain type amplifier" in the title.
Again, I'm not trying to make a preamp, I'm trying to make a full amplifier that includes a power amplifier.
It refers to an amplifier that does not overdrive the power amplifier much because the distortion is mainly obtained from the preamp.
In any case, the tube rectifier has some advantages, but it doesn't seem like you have to make a tough choice. Thanks for the good answers!
There seems to be a little confusion because of the text "preamp gain type amplifier" in the title.
Again, I'm not trying to make a preamp, I'm trying to make a full amplifier that includes a power amplifier.
It refers to an amplifier that does not overdrive the power amplifier much because the distortion is mainly obtained from the preamp.
In any case, the tube rectifier has some advantages, but it doesn't seem like you have to make a tough choice. Thanks for the good answers!