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pedals 4 pv
Platinum Member
Canada
1351 Posts |
 Posted - 12/03/2007 : 22:38:26
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I have been studying tube amp schematics to find out if I could add a standby switch to my Classic 30, this leaves me couple of questions. As this amp has a solid state rectifier, would the addition of a standby switch even be worthwhile? If I turn all the volumes to 0, reducing the grid voltages to 0, does this not do the same as the standby switch?
Is it better to turn the amp on and let it warm up with all volume controls at 0? Because it seems to me that would extend tube life if you dont have a standby switch. |
Edited by - pedals 4 pv on 12/03/2007 22:39:49 |
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jack
Platinum Member
USA
1418 Posts |
Posted - 12/03/2007 : 22:50:39
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If your amp has no standby switch, make sure to turn all volumes and gains down to zero before turning the amp on or off. When you turn it on, let it warm up for about a minute or so before turning up. I think this will save your tubes a bit. As far as whether a standby swicth is needed, for my 5-watt Epiphone Valve Junior heads, its a bit overkill, but might not be a bad idea for a larger wattage tube amp. I'm sure others will have more to say on this as well, but thats just my view of it.
Turning the volumes down to zero is sort of like a standby switch, but not exactly. Here's a couple of articles on Standby Switches and what they do, and whether they are needed:
http://www.musictoys.com/gearhead/gear14.php
http://www.rru.com/~meo/Guitar/Amps/Kalamazoo/Mods/standby.html |
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FRANZONI
Double Platinum Member
Ireland
3543 Posts |
Posted - 12/04/2007 : 01:42:44
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i have standbys on two of my amps and none on the selmer 15 watt combo..i find the selmer goes through valves little quicker than the others even when turned on with the volume down..but then it is class A and gets very hot..it has in total,nine valves in it between the preamp,rectifer,tremolo and output stages and it's about 46 years old...... ...... i only use it in the house these days...but it would be a very cool amp for a quiet blues session,i suppose i could always mike it if i needed to be a bit louder with it but it still packs quite a punch for such a small amp..i'll try to posts some pics soon.. |
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 12/04/2007 : 04:19:21
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Those are good links Jack, thanks they are very informative.
Franzoni, post those pics so we can see your Selmer.
So, without a standby switch what could I reasonably expect for tube life, if I always turn it down? I play 1 to 2 hours in a day, but in 3 or 4 little sessions. If I am planning to take a break for 15 or 20 minutes I just turn everything down, but longer than that I shut it off. Could I take a longer break without shutting it off, or is this to long, and how long should you let the tubes cool before you restart it after you do shut it down?
It probably doesn't need a standby or it would have had one when it was made, but, I tend to fret about such matters and I am a cheap old bastard so I want the tubes to last as long as possible. |
Edited by - pedals 4 pv on 12/04/2007 06:45:24 |
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Big Boss Man
Gold Member
USA
564 Posts |
Posted - 12/04/2007 : 12:48:54
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| pedals 4 pv, I am not that knowledgable on the technical stuff but I did have a Classic 30 for about 10 years. I always kept the volume at zero when turning it on and off. I never had to change the tubes during the entire 10 years I had the amp. I did not really use the amp extensively or play at very loud volumes so that may have extended the tube life as well. |
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 12/04/2007 : 22:20:59
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Thanks Big Boss Man it's good to get feedback from someone who has actually owned one, and has no axe to grind. I could read Harmony Central or one of the other sites that have owners revues but it's always some guy that thinks his $400 dollar Blues Jr. should sound just like a $6000 Marshall stack, or I got took on this American Strat, my two chords don't sound any better than they did on my Squire.
Ten years sounds like a good long while for the tubes to last and I'll be happy to get half of that, so the standby switch idea can be put to rest. I am a firm believer in the concept of "if it ain't broke don't fix it". |
Edited by - pedals 4 pv on 12/04/2007 22:26:56 |
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FRANZONI
Double Platinum Member
Ireland
3543 Posts |
Posted - 12/05/2007 : 02:49:38
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Sorry if i gave the wrong impression about the power amp valve life question..my belief is with my selmer the amp because it has such small wattage it tends to get driven that bit harder..i used to use it for rehearsing all the time and even went through a phase of only using it and my squier strat with the clapton mid boost system installed..no pedals... it really is a great sound to try sometimes controlling the amp with the guitar and no effects....but the cost of this is power amp valves...i reckon i got about two years out of the last pair and that was running the amp nearly full tilt for about two/three hours,one or twice a week for a couple of years previous..... all the preamp/rectifer/tremolo valves seem to be ok..so i'll probably order a couple of el 84's off the 'net soon for it...i also need to get some power amp valves for the musicman because the way my amp is designed,it has a 12ax7 as a phase splitter but has a solid state preamp and a valve power amp to keep it clean(musicman amps were originally designed for country players)but the down side of this is,as i have found out is when the phase inverter goes south it can take the power amp valves with it in this type of amp design..... and worst case scenario it takes the output tranny as well..... as it turned out musicman recalled a lot of these amps in the 70's and reissued them with a fully solid state preamp/inverter stage but they aren't supposed to be a sweet sounding as the one i have.... and i can't really complain i have this amp 20 years and i've only changed the splitter valve twice..... and the power amp valves the same..... and it has been my main 'go to' amp for gigging... BTWthe amp itself is over 30 years old.......... |
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 12/05/2007 : 06:56:56
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No, you didn't give me the wrong idea, Franzoni. I am just trying to learn what I can about my amp
quote:
Originally posted by FRANZONI
it really is a great sound to try sometimes controlling the amp with the guitar and no effects....
I have hardly used my distortion or overdrive pedals since I've got my tube amp. However, I found a good deal on a FZ-2 today so I guess I'll fool around with that tonight.
It's like going from single coil pickups to humbuckers, the pedals act totally different. The difference in the way my CS-3 works with the tube amp is amazing.
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Edited by - pedals 4 pv on 12/05/2007 08:31:04 |
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Standby switch on tube amp
