Tube vs. Solid-State Rectification

Which sounds better, in general? Does it even matter?

 

I'm not putting a tube or a transistor in there to find out. Buh-dum-bump!

I've read, but do not know that tubed has a more breath of life but mushier sound, whilst solid state has more control at the frequency extremes. On the other hand, I don't know what rectification in a tubed amp is exactly. Any layman explanations?

 

Hello!

The rectifier blocks AC. I have tube amps with both. With tube rectifiers you can roll the tubes, although these don't have a profound effect on the sound from my experience. I will let someone else chime in on their experience. Peace. Robert

 

Recification is defined as transforming an AC signal into a DC signal. From that definition and assuming equal filtering of the recified signal via big *** capacitor banks, I can't see how there would be a difference in sound between tube and SS. Its in the amplification of ac signals where the sonic differeence would become apparent due to the inherent charcteristics of tube and SS device. But as rectifiers which convers it to DC, I don't think its possible ot hear.

 

Based on my DIY creations - I prefer to use tube rectification - slow voltage ramp up, less 'switching' noise and the ability to change your B+ depending on the rectifier used (5R4, 5AR4, etc).

However solid-state rectifiers can sound good provided you design carefully with snubbers and use some of the latest fast devices.

 

http://www.guitaramplifierblueprinting.com/rectifiers.html


http://thegearmall.com/product-demos/amplifiers/understanding-solid-state-versus-tube-rectifiers


http://en.wikipedia.org/wiki/Rectifier

 

I'd use tube in a guitar amp, solid state in high-fi

The tube can cause voltage sag which sounds like compression - great for a guitar amp

The SS can use bigger capacitors for filtering, (this is why tube rectifiers are described as bass mushy, it's the caps not the tubes)

 

depends on the circuit - for example with a choke input following the tube rectifier, you can use big banks of capacitors (blah!). Also, with pure class A amplifiers, you get less rectifier sag since the current requirements are fairly constant. For a big Class AB power amplifier however, I would run either solid state diodes or a pair of TV damper diodes.

Power supply design is always a juggle of different variables.

 

That's a good analogy. It isn't quite as cut and dry however as dividebytube has elaborated. I agree with both of you! There are some guitar amps that sound great with tube rectification, but that has to be the sound that you are after. Other guitar amps sound best with SS rectifiers.

As for playback, it is always SS for accuracy and again as dividebytube as indicated, there are some choices of these components which provide better results than others. Circuit design is as important as component choice however as you can't get a great sound simply by installing great components in a poor circuit. I have had some tube amps with tube rectification (and still do) that I thought sounded great for what they were, but they color the sound. If you like the color, then so be it, but don't confuse it with being "better" as it is just "different". It becomes a matter of taste whether to color the signal in that way or not. Early digital could be made to sound smoother and more "open" in that way. Really good recordings will lose transparency and resolution when processed that way however.
-Bill

 

And then there is also SS Regulation and Tube Regulation...No???

 

Funny I was going to ask the same question. I currently have two RCA 5U4G rectifier tubes in my amp. They can easily be swapped out with these little SS rectifiers. I've heard they can help a SET amplifier sound more punchy and tight in the bottom end. I had a different SET amp before with SS rectifiers and it did have a little more solid bass and was a bit louder, like an extra watt with certainly helps with a SET amp.

 

Yes, they will do that. They can also prevent expensive repairs if a rectifier tube fails. While they offer better bass performance, they will diminish the softer and more fluid mids. It is cheap enough to give a try.
-Bill

 

As mentioned, a tube would allow for some sag in DC voltage which would affect the overall power and sound.

In audio though, I don't know for sure if that would be preferable. In a guitar amp, the sag would mean more saturation in the output stage which would result in more tonal crunch. This is what I would prefer in my guitar amp but not in a bass amp.

For bass guitar I prefer full solid state to achieve a balls out punch.

 

This is exactly the way my amp is, with a choke input, tube rectifier and a big bank of capacitors. It is a Class AB. It sounds great to my ears without sounding compressed or tubby in the bass.

 

I put this same question to our host a long time ago:

http://stevehoffman.tv/forums/showthread.php?t=1556&highlight=rectification