Bare Knuckle Pickups Forum

Forum Ringside => Guitars, Amps and Effects => Topic started by: sgmypod on July 26, 2011, 08:09:17 PM

Title: rectifier - valve or solid valve a like?
Post by: sgmypod on July 26, 2011, 08:09:17 PM

So question is has anyone tried this valve rectifier replacements any good or plain cr@p

Title: Re: rectifier - valve or solid valve a like?
Post by: sgmypod on July 27, 2011, 07:18:58 AM

Anyone?

Title: Re: rectifier - valve or solid valve a like?
Post by: Dmoney on July 27, 2011, 10:09:07 AM

you mean like the weber copper cap's?
No. I've not.
But I have owned a dual rec with both types of rectifier.

not sure how much a solid state valve rectifier replacement can actually emulate the response of a valve rectifier (like the weber things claim) but they might emulate the voltage drop quite well. normally if you just stick SS Diodes in place of a valve rectifier you get an increase in HT voltage since the diodes are more efficient at rectifying the AC. Could be a problem if the filter caps in the power supply are run at their DC voltage limit. Other than that, increased HT will make the amp sound tighter and you'll get less 'sag' in theory. The weber caps might recreate the voltage drop of a particular valve rectifier, by using diodes and then dropping the voltage inside the rectifier by a known percentage, potentially giving you the same tone, if the voltages remain correct, but the feel might still change a bit.

someone who knows more about rectifiers might have a better idea

Title: Re: rectifier - valve or solid valve a like?
Post by: jpfamps on July 27, 2011, 11:39:58 AM

The Weber Copper Cap contains couple of diodes, a couple of power resistors to simulated the impedance of the rectifier, and a thermistor to limit in rush current.

My experience with them is that they do a very good job, although the 5Y3 version drops more volts than most real 5Y3GBs.

Even with the in rush current limiter, the Copper Cap will turn on faster than a valve rectifier.

The impedance of valve rectifier, being used sensibly, is more or less linear, so an appropriately sized power resistor after a solid state rectifier causes the power supply to sag in a very similar fashion.

Title: Re: rectifier - valve or solid valve a like?
Post by: HTH AMPS on July 27, 2011, 12:09:51 PM

I've used the GZ34 Copper Caps for years - great pieces of kit.  This was back from around 2001/2 when Sovtek were the only new ones you could get and they rattled like mad.  I was gigging Selmer T&B mkII heads at the time and had a couple of GZ34s die on me mid-set, the Copper Caps were great - didn't notice any difference in tone/feel.

Title: Re: rectifier - valve or solid valve a like?
Post by: sgmypod on July 27, 2011, 12:15:12 PM

Cool that answers another question, had seen sovtek ones, is there any good stockists of the copper ones

Title: Re: rectifier - valve or solid valve a like?
Post by: HTH AMPS on July 27, 2011, 12:57:45 PM

order direct from Weber in the US.