I just acquired a Fender Brownface Deluxe guitar amp manufactured in 1962. It's my first amp I've been exposed to with a tube rectifier. I've realized there's another positive benefit of utilizing a tube rectifier over a solid state type, ie no "standby" switch is required. Since the rectifier tube warms up at the same rate as the other tubes, B+ isn't applied until everyone is thermionically eschewing electrons. That's a very nice automatic feature eliminating the manual standby switch.
This amp uses two 6V6 output tubes in push pull. The tremolo is to die for. It modulates the output tube bias. I think it's easily the best tremolo I've ever heard.
It's a great "small venue" rock guitar amp in that it will break up at tolerable volume levels yet has a reasonable clean level on lower settings.
This amp uses two 6V6 output tubes in push pull. The tremolo is to die for. It modulates the output tube bias. I think it's easily the best tremolo I've ever heard.
It's a great "small venue" rock guitar amp in that it will break up at tolerable volume levels yet has a reasonable clean level on lower settings.
The 6CA4/EZ81 (6.3V @ 1 Amp Heater) should not be overlooked either.
I built a Tiny Terror Clone using PP 6GW8/ECL86 with a 6CA4 rectifier - glorious
Cheers,
Ian
I built a Tiny Terror Clone using PP 6GW8/ECL86 with a 6CA4 rectifier - glorious
Cheers,
Ian
Receiving tubes are specifically designed to NOT be in danger of cathode stripping when used by non-technical persons.
"Standby" is for taking a break (silently) yet being ready for instant action.
If it were really important, Fender would have used a delay-relay. Dynaco actually did; on their BIG 120 Watt amplifier where the turn-on "tunk" threatened lesser hi-fi speakers.
No rectifier bridge snubber required either to filter out the nasty .7 v edge that happens 100 or 120 times per second.
Enough warnings about cathode stripping out there, I protect my inventory of 78 vacuum tubes by maintaining the tube rectifiers. You can still buy new rectifier tubes, but the 7199's 6267's & ef86's have gone the way of the dodo bird. Even 7591's are about $50 the pair.
5AR4's aren't fragile. I've 4 hammond originals in the 2 home use H100's still putting out nominal B+. The church use H182 came with a new 5U4 instead of 5AR4, but it was because the lazy tech didn't want to replace the B+ electrolytic caps to boost the inadequate volume. Nothing wrong with the 1968 original 5AR4 laying in the back in the 5U4 box. I used to wear out a 5AR4 about every 4 years in my ST70 dynakit amp that was left turned on ~2000 hours per year. I listen to FM radio a lot longer than anybody plays his Hammond. Maybe Jimmy Hendrix would wear out a tube rectifier: he reportedly practiced guitar nearly all the time he was awake.
Enough warnings about cathode stripping out there, I protect my inventory of 78 vacuum tubes by maintaining the tube rectifiers. You can still buy new rectifier tubes, but the 7199's 6267's & ef86's have gone the way of the dodo bird. Even 7591's are about $50 the pair.
5AR4's aren't fragile. I've 4 hammond originals in the 2 home use H100's still putting out nominal B+. The church use H182 came with a new 5U4 instead of 5AR4, but it was because the lazy tech didn't want to replace the B+ electrolytic caps to boost the inadequate volume. Nothing wrong with the 1968 original 5AR4 laying in the back in the 5U4 box. I used to wear out a 5AR4 about every 4 years in my ST70 dynakit amp that was left turned on ~2000 hours per year. I listen to FM radio a lot longer than anybody plays his Hammond. Maybe Jimmy Hendrix would wear out a tube rectifier: he reportedly practiced guitar nearly all the time he was awake.
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5Y3's heat up and start conducting after just 3 or 4 seconds, long before indirectly heated tubes elsewhere in the amplifier do. It's not as abrupt as the SS rectifiers are, but enough to temporarily overvoltage things.
Yes but in a modern design, you can add for low value a timer to avoid powering the lamp before it should: LM555 + Relay for example but I prefer eFuse or Load Switch for that (no mechanical part). It is automatic and you have a solid-state PSU. Say that, I'm not sure a solid state PS would be better than a tube regulator (yes, regulation, noise and so on are better with a solid state PSU BUT is audio sound better in the speaker?)