Members nuke_diver Posted February 27, 2008 Members Share Posted February 27, 2008 Have you ever had to replace the tube? I have a feeling mine is going but I don't have experience with them so I'm not exactly sure how they go. I remember that the tubes in our old TV would fade out rather than just blow. I think this is happening to mine. The glow seems much fainter than before and occasionally I've noted some changes in volume. The tube is probably 3-4 years old (I can't quite remember when I bought the amp). Would this be the expected behaviour of how it would go and is this the expected lifespan (amp is used pretty much every day for 1-3 hrs I'd say). Thanks Link to comment Share on other sites More sharing options...
Members Andrewrg Posted February 27, 2008 Members Share Posted February 27, 2008 Have you ever had to replace the tube? I have a feeling mine is going but I don't have experience with them so I'm not exactly sure how they go. I remember that the tubes in our old TV would fade out rather than just blow. I think this is happening to mine. The glow seems much fainter than before and occasionally I've noted some changes in volume. The tube is probably 3-4 years old (I can't quite remember when I bought the amp). Would this be the expected behaviour of how it would go and is this the expected lifespan (amp is used pretty much every day for 1-3 hrs I'd say). Thanks Yep, probably time for a change if you've been using it a lot. You'll notice the electrodes inside the valve (tube) becoming pitted and the silver coating becoming dull. There may be some scorching around the valve base too. Get a new one; they're nice and cheap! Link to comment Share on other sites More sharing options...
Members Rhythm Junky Posted February 27, 2008 Members Share Posted February 27, 2008 Good luck trying to figure out a way to change it. Link to comment Share on other sites More sharing options...
Members drawdeep Posted February 27, 2008 Members Share Posted February 27, 2008 Hmm, might be about time for mine to be changed too... Sorry to hijack the thread, but does anyone know what would be a good replacement for mine (12AX7 in a AD30VT) that would maybe be a little more suited to high-gain sounds? Link to comment Share on other sites More sharing options...
Members Doctor Morbius Posted February 27, 2008 Members Share Posted February 27, 2008 If it's 3 to 4 years old and the amp has seen regular use I would change it simply because those tubes are cheap. I paid $16 for a Sovtek 12AX7LPS, which was probably a bit too much. I've seen Fender preamp tubes for $10 at Sam Ash. DrawDeep, the place I bought my tube from recommended the Sovtek 12AX7LPS for higher gain applications on my AD30VT. I still have the stock Electroharmonix tube in my Vox half stack because it's basically brand new. The AD30 I bought used so I just went ahead and swapped out the tube while I had the amp apart and was putting in cabinet dampening material. Link to comment Share on other sites More sharing options...
Members Doctor Morbius Posted February 27, 2008 Members Share Posted February 27, 2008 Good luck trying to figure out a way to change it. It's not that difficult. Link to comment Share on other sites More sharing options...
Members nuke_diver Posted February 27, 2008 Author Members Share Posted February 27, 2008 Good luck trying to figure out a way to change it. Is it that hard to get too? I was checking a site for Valvetronix stuff and found this Q1) Sometimes the tone/volume quality can drop, or sound only comes out of one channel, or I get crackling. Why is this happening? A1) Although the concept of the Valvetronix amp is superb, they are built to specific budgets. The jack plug sockets used are 'adequate' but they aren't the best. Two problems can occur - (i) the jack socket gets dirty & becomes oxidised, creating a bad contact and lowering sound quality &/or volume (ii) the jack-plug connector pincers inside get 'stuck' and stay open. SOLUTION - just spray some electrical switch cleaner (not WD40) into EVERY jack plug socket, and push a jack-plug in/out several times. This will clean the socket, and release any 'sticking' jack plug. If your amp is older you may need to repeat a few times to get the contacts clean. It's also a good idea to spray some switch cleaner into your guitar jack socket and tone/volume pots if you haven't done this for a while too! In fact, by doing this every 6mths or so, you could save yourself ever having the problem - prevention is better than cure! Any comment? There was a post suggesting that the power tubes would likely last (the word forever was used but that is a very long time) Link to comment Share on other sites More sharing options...
Members Doctor Morbius Posted February 27, 2008 Members Share Posted February 27, 2008 Is it that hard to get too? I was checking a site for Valvetronix stuff and found this Any comment? There was a post suggesting that the power tubes would likely last (the word forever was used but that is a very long time) Did you take shop in high school? If so you can easily swap a tube in the chrome Valvetronix series. It's not difficult. Also, changing that input jack for a decent one isn't difficult either. The guys on that forum are using scare tactics. When you have the amp apart to change the tube double check the input jack. If it looks fine leave it alone. You may want to bend the tension arm a little bit so that it has that 'snap' when you plug in a cable. Link to comment Share on other sites More sharing options...
Members drawdeep Posted February 27, 2008 Members Share Posted February 27, 2008 DrawDeep, the place I bought my tube from recommended the Sovtek 12AX7LPS for higher gain applications on my AD30VT. I still have the stock Electroharmonix tube in my Vox half stack because it's basically brand new. The AD30 I bought used so I just went ahead and swapped out the tube while I had the amp apart and was putting in cabinet dampening material. Cool- thanks! Link to comment Share on other sites More sharing options...
Members nuke_diver Posted February 27, 2008 Author Members Share Posted February 27, 2008 Did you take shop in high school? High School was a very very long time ago. The comment was good luck changing it. Sometimes manufacturers don't consider easy of replacement as part of the design (remembers a water pump replacement that required dropping the engine). If it is easy to change great, if it is only a slight pain no problem I think I can handle it. The real question is does the tube wear out slowly causing loss of volume and tone. If not then its something else like the connection (since the setup is Amp ->wah->guitar the amp gets unplugged less so the connector is more likely to be the guitar) Link to comment Share on other sites More sharing options...
Members Doctor Morbius Posted February 27, 2008 Members Share Posted February 27, 2008 High School was a very very long time ago.It was for me too, but still, changing the tube in the chrome Vavletronix series is no more difficult than building your own time/space dimensional teleporter, a crystalline multi-phasic storage device or an Interociter. Link to comment Share on other sites More sharing options...
Members _pete_ Posted February 27, 2008 Members Share Posted February 27, 2008 It was for me too, but still, changing the tube in the chrome Vavletronix series is no more difficult than building your own time/space dimensional teleporter, a crystalline multi-phasic storage device or an Interociter. Wow. First fire, then the wheel, and now this? You cavemen rock. Link to comment Share on other sites More sharing options...
Members cratz2 Posted February 27, 2008 Members Share Posted February 27, 2008 Well, usually preamp tubes last basically forever, but since this is a preamp tube acting in more of a power tube emulator capacity, maybe they need to be replaced more often. I've had my AD30VT apart a few times and I think I could change the tube in about 5 minutes with a drill. Unplug it, let it sit for a couple minutes. Take the back off, take the chassis out, slide the chassis out, remove the tube, insert the new tube and put it back together. It's a lot of screws... about 16 I guess of two different sizes. But they don't give you a lot of room between the top of the tube and the chassis to get your hand in there. And it's almost impossible to see the pin holes on the socket once the tube is out, so it will benefit you to see where the skipped space is when you're pulling the old tube out. Actually, as noted, I'd probably remove the tube and re-insert it several times (no middle jokes here ) before installing the new tube. That should do a decent job of cleaning the socket. In all honesty though, I think they planned on the tube never having to be replaced. Link to comment Share on other sites More sharing options...
Members balthazarr Posted February 27, 2008 Members Share Posted February 27, 2008 Once you get the tube out, mark the space between the pins with whiteout, carefully.IT will make it easier to orient the tube when replaced. Providing you can see the socket, that is. Link to comment Share on other sites More sharing options...
Members paul6string Posted February 27, 2008 Members Share Posted February 27, 2008 I seperated the circuit boards to make it easier. Mine came with a defective tube, and acted up after two weeks. Without taking the board apart, there's virtually no room to maneuver your hands in there. Link to comment Share on other sites More sharing options...
Members nuke_diver Posted February 27, 2008 Author Members Share Posted February 27, 2008 It was for me too, but still, changing the tube in the chrome Vavletronix series is no more difficult than building your own time/space dimensional teleporter, a crystalline multi-phasic storage device or an Interociter. Well you're way ahead of me then, I can't get my transmogrifier to work at all Link to comment Share on other sites More sharing options...
Members bungholio281 Posted February 27, 2008 Members Share Posted February 27, 2008 I know a guy who used a tube from a Mesa Roadster in it, and he says it now has more body and a more full sound. I might try it Link to comment Share on other sites More sharing options...
Members cratz2 Posted February 28, 2008 Members Share Posted February 28, 2008 I will say that I tried different tubes in both my AD30VT and in my original Tonelab. They made VERY little difference. The stock tubes are about the worst tubes on the market though so it would be virtually impossible for a tube swap to make it sound any worse. I tried the stock tubes, Groove Tubes Gold 12AX7, Groove Tubes Gold 12AT7 Groove Tubes Silver 12AX7 and a Tung Sol from Guitar Center. In my Peavey Prowler, they each made a pretty noticable difference... In the AD30 and in the Tonelab, not so much. Still, I couldn't bring myself to put the stock tube back in the Tonelab (which is part of my main rig) so I left the Gold 12AX7 in there. Overall, it won't make much, if any, of a difference. On the other hand, it's only a $10 to $20 swap so why not. Link to comment Share on other sites More sharing options...
Members tlbonehead Posted February 28, 2008 Members Share Posted February 28, 2008 I will say that I tried different tubes in both my AD30VT and in my original Tonelab. They made VERY little difference. The stock tubes are about the worst tubes on the market though so it would be virtually impossible for a tube swap to make it sound any worse. I tried the stock tubes, Groove Tubes Gold 12AX7, Groove Tubes Gold 12AT7 Groove Tubes Silver 12AX7 and a Tung Sol from Guitar Center. In my Peavey Prowler, they each made a pretty noticable difference... In the AD30 and in the Tonelab, not so much. Still, I couldn't bring myself to put the stock tube back in the Tonelab (which is part of my main rig) so I left the Gold 12AX7 in there. Overall, it won't make much, if any, of a difference. On the other hand, it's only a $10 to $20 swap so why not. My AD30 came with an EH, which I like as a preamp tube. Link to comment Share on other sites More sharing options...
Members tlbonehead Posted February 28, 2008 Members Share Posted February 28, 2008 Well, usually preamp tubes last basically forever, but since this is a preamp tube acting in more of a power tube emulator capacity, maybe they need to be replaced more often. I've had my AD30VT apart a few times and I think I could change the tube in about 5 minutes with a drill. Unplug it, let it sit for a couple minutes. Take the back off, take the chassis out, slide the chassis out, remove the tube, insert the new tube and put it back together. It's a lot of screws... about 16 I guess of two different sizes. But they don't give you a lot of room between the top of the tube and the chassis to get your hand in there. And it's almost impossible to see the pin holes on the socket once the tube is out, so it will benefit you to see where the skipped space is when you're pulling the old tube out. Actually, as noted, I'd probably remove the tube and re-insert it several times (no middle jokes here ) before installing the new tube. That should do a decent job of cleaning the socket. In all honesty though, I think they planned on the tube never having to be replaced. V1 especially needs to be replaced periodically in my amps. I work them pretty hard. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.