Sorry if I offend some with this question. I've been told by a couple of tube-heads (one a guitar amp guy) by replacing the rectifier tube with a Weber Copper Cap an amp will run cooler and will have more reserve power. Any truth to this? If so, will this make a better sounding tube amp?
Thanks
Sam
Thanks
Sam
Assuming it's just some silicon rectifiers in a copper package, it will do all that's claimed. But... you have to be careful that there are no components in the amp which require a slow warmup time. And there really won't be that much more power, maybe not even enough to be noticeable. And it may change the amp's overload characteristics.
But, hey, it's $20, not $200. Give it a try.
But, hey, it's $20, not $200. Give it a try.
SY said:
Thanks, Sy
From Weber's website: "has linear in-rush current limiting to simulate the warm-up of a tube rectifier, however, it is in the 1 to 2 second range, rather than the 7 to 9 seconds of a typical rectifier tube"
http://www.webervst.com/ccap.html
SY said:
Hey,, I think I saw a bin of hundreds of those in a local plumbers supply house when I was installing the gas dryer here.
Seems to me, years ago radio electronics had a "How To" on a near look alike. I think it was praised more for reliabilty back then. Long time ago so dont quote me on that lol
Gene
Many years ago (when I was a mere stripling) I bodged an EL84 amplifier. I didn't have room on my chassis for the EZ81 that was supposed to be there, so I used 2 x BY127 (silicon). The amplifier had bags of power. When I was able to borrow a multimeter, I found out why. The HT was nearer to 430V than 300V. The (Mullard) EL84 finally expired in a firework display from my abuse...
If the filament winding for the rectifier shares the core with the plate supply, the B+ will likely go up, possibly above maximum recommended for the output tube. If you are using Chinese or Russian tubes, things are dicey enough. I'd stick with the 6CA4; they're cheaper and probably sound better.
...like output tubes.
John
Probably because the so-called "more reserve power" is really just more louder distortion.
Replacing tubes is a way of life with gui-tar players. So much so, they keep Russian tube manufacturers in business. Which is why we audio guys are stuck with EL34's, 6L6's, and the like to play with...yawn.
John
Oh, let's not get into some us versus them turf war. In a guitar amp, replaing the tube rectifier with a SS one does not just result in "more louder distortion."
The two systems of rectification have a different dynamic in the amp. The tube rectifier results in a lower B+ voltage than the SS rectifier, but it also results in "sag." When a loud signal passes through, it causes the B+ to drop, moreso than just what the draw from the transformer would cause. This is due to the internal resistance of the rectifier tube. The sag introduces a bit of compression into the sound which in turn increases "sustain." Sustain means the note rings a bit longer. This makes the amp more expressive.
Blues and Jazz players like the tube rectifier sag, while the solid state rectifier with its consistent voltages is more to the liking of the metal crowd.
Weber markets to guitar players, that would explain its popularity in that market.
Better sounding is a matter of taste. As to having more reseerve power, I am not sure that an extra 20-30 volts on B+ will translate into a lot of added power. DOubling the power is only a 3db advantage in loudness.
The two systems of rectification have a different dynamic in the amp. The tube rectifier results in a lower B+ voltage than the SS rectifier, but it also results in "sag." When a loud signal passes through, it causes the B+ to drop, moreso than just what the draw from the transformer would cause. This is due to the internal resistance of the rectifier tube. The sag introduces a bit of compression into the sound which in turn increases "sustain." Sustain means the note rings a bit longer. This makes the amp more expressive.
Blues and Jazz players like the tube rectifier sag, while the solid state rectifier with its consistent voltages is more to the liking of the metal crowd.
Weber markets to guitar players, that would explain its popularity in that market.
Better sounding is a matter of taste. As to having more reseerve power, I am not sure that an extra 20-30 volts on B+ will translate into a lot of added power. DOubling the power is only a 3db advantage in loudness.
Thanks to the links it's now easy to make an educated guess.
Cooler? Yes, of course. More reserve power? No. It seems the emulation is quite accurate judging by the voltage drop. The amp will have pretty much the same power as before.
Better sounding? I very much doubt this. These parts are manufactured for long life and convenience and certainly not to enhance the sound. They clearly contain some kind of SS circuit inside; maybe an SCR and controlling circuit to achieve delay. Hopefully there is no additional RF noise coming from the control circuit.
Even if one prefers the sound of SS rectifiers (mostly due to low internal resistance) this combines the worst of both worlds. And no, i don't think they are using Shottkys inside
Plenty of Warsaw Pact and NATO surplus out there to keep me happy. I get my GM-70's and 6C45p's more cheaply than KT-88's and 12AX7's and they are much better tubes. Use your imagination and you can do great things with tubes like EC86, EC88, GK-71, 6C33, C3m, 6C19 etc. I'm talking DIY here, not scam $10,000 6L6 "high end" amps.
John
Sam, certainly we like distortion. The SS rectifier does not provide it, that's all. We overdrive the early stages to get it. WHen you get to the likes of Jimi and Eddie Van Halen, they play full out at concert stage volumes and at those levels, in addition to preamp distortion, we also get power tube distortion, which is a different sounding efect and desirable for many. SO desirable in fact that they make products of various names like Power Soak and Power Brake which are basically dummy loads. These are used so the amp can be cranked to full output power to get power tube distortion, but with much of the power going into the dummy load so you can get the effect without having it so darn loud.
Inrush limiting can be either a simple resistor or if you want to get fancy, a thermistor.
Inrush limiting can be either a simple resistor or if you want to get fancy, a thermistor.
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