The grill is easily fixed by buying one at Fliptops Home of Parts for Ampeg Lovers and a little extra money. I'd probably do the one at Sam Ash because it's ultimately way more convenient.
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2013 Ampeg V-4B 100W Reissue Pt2
- Thread starter Chef
- Start date
It's a tough decision but as of now I am headed down to Tampa for work Wednesday so it won't cost me anything gas wise to buy it. For $1,000 I figured it would take care of the expense of new power tubes when compared to the Sam Ash price. If I need new power tubes ($250) in the Sam Ash along with front grill ($42), logo ($15), tax ($78) I am looking at a total cost of $1,685 vs $1,250. Now that is if they need replacement power tubes. I may call down there tomorrow to see if the VR they have was made in the US and if they know the condition of the tubes. Not that it matters much but I do like my US made Ampeg gear.
The one catch of buying at Sam Ash is if there is a problem within 30 days I can return it. Craigslist you're SOL.
If the guy replaced 4 of the 6 tubes with Winged C matching pairs (so not all 4 or 3 for that matter were matching) is there anything with the internals of the amp that can be affected by doing this. I am already going to replace the tubes but I want to make sure using unmatched power tubes does not hurt the amp beyond sound and tube life.
Using the -15db input on the V4b and into the 210AV is about as ideal a low level at home practice amp as can be imagined. I know I asked the question 10 different ways for a few weeks but it really worked out to be the most ideal solution. I am also finding that that I can also make this little sealed beast a little more like a modern tweeter/ported cabinet with the Ultra High engaged and adding the ultra low scoops it for that more modern tone. Really a very versatile little combo that gets pretty darn loud when you move to the 0db input.
It can run the amp unevenly or something. ..Power tubes should be biased by someone who knows (a good tube amp tech) when they're replaced.
I know the tubes themselves can be games of they're outta whack, dunno just how much the amp will suffer.
Ask TBer @B-string he knows a lot re this sorta stuff.
How safe it is depends on the extent of the mismatch. Every amp can handle mismatched tubes to some extent. How much so depends on the amp design.
With the SVT-VR you have two sets of three power tubes. Each trio is connected in parallel and their currents sum. If they are mismatched, some tubes will be working harder than others. The amp basically sees one big tube on one side and one on the other.
If the tubes are badly matched, you may not be able to set the bias. The VR has a balance control on the back. This allows you to equalize the combined current from each power tube trio. By doing this, you help minimize distortion that unequal currents on each side can create. If the tubes are really mismatched you may not be able to set the balance.
Of more concern is the possibility of the tubes going into oscillation. This can happen if the tubes are very poorly matched. An oscillation can damage your amp. The possibility of this happening is rare. Symptoms can be a squealing or a popping sound. If you hear this, shut the amp down.
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So assuming for the past 4 years he used unmatched tubes would you purchase the amp?
If you are worried that unmatched tubes damaged the amp, don't be concerned. Time has shown that it isn't an issue. If the amp sounds fine, it is. Depending on how much the amp has been used, you might need to buy a new set of tubes before long.
Haven't been back here in a while... busy with life. V4B still sounds great, though no gigs lined up till August, which sucks. Also till running mine through Mesa cabs and not sure if I want to continue to do so or get something else. I'd love for everything to match but at the same time the setup I have now sounds great so I don't know if I want to mess with it.
I did order a cover for my V4B from Invalid Link Removed I had them increase the length of the cover 1/4" because what they had for dimensions looked to be a little short. The cover showed up in about 3 weeks and they did a KILLER job with it. I highly recommended them those who want a padded slip cover for their amps. I even had them add a pocket to the back to store the power cable and speaker cable for gig transport (I'm only running my Shure GLXD wireless with tuner into the front of the amp).
I did order a cover for my V4B from Invalid Link Removed I had them increase the length of the cover 1/4" because what they had for dimensions looked to be a little short. The cover showed up in about 3 weeks and they did a KILLER job with it. I highly recommended them those who want a padded slip cover for their amps. I even had them add a pocket to the back to store the power cable and speaker cable for gig transport (I'm only running my Shure GLXD wireless with tuner into the front of the amp).
Burwabit
Likes guitars that tune good and firm feelin women
That's an interesting cover. Never seen those. I usually shy away from buying this kind of thing because I inevitably trade out amps. However, I feel like the V4B is here to stay. I see a long term relationship developing.
Did you get the Clamshell or Slip Cover?
I tired these 5751's in V1 of my V-4B RI to see if I get a little more clean volume. The Sylvania went in first and I loved the sound. It was a great deal warmer than the stock JJ, and with the gain all the way up and the master at 4, it was super clean. The Philips had the same cleanliness, but it was as bright as the JJ. I'm going to give them a try in my SVT-CL also.
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Back to having this problem again. Checked all the tubes and none were loose this time (last time one pretty much fell out on its own). Doesn't seem like any tubes are having problems firing up and getting warm either. Anybody else experience this problem? If a tube goes bad does your amp turn into a distorted mess? This is my first tube amp (bought used from a member here) and i'm starting to worry there might actually be a problem with the amp.
You can try to narrow down where the issue lies. If you have another preamp, feed it into the power amp in and see if you get the distortion. If no, the issue is most likely in the V4B preamp.
If the tube V4 in the power amp, the 12AU7 is weak, it can cause this type of distortion. Try changing it.
Try slipping the tubes out and then in. It should take a certain force to do this. If they are coming out too easily, the tube sockets are not tight enough on the tube pins. The sockets need to be pinched closed a bit, this is called re-tensioning. This could cause the problem that you are describing. It can happen if different tubes with larger pins were inserted into the amp. The socket contacts can get stretched open and prevent good contact.
Thanks for the replies guys! I will try those suggestions beans but i'm not understanding the "If the tube v4 in the power amp, the 12au7 is weak, it.....". The power amp uses all 6l6gc i thought. Did you mean preamp? Also, I don't think the 12au7 is the v4 slot (the v # is referring to slot i'm guessing cause I honestly don't know). A bit mixed up now.
The 12AU7 in your amp is the driver tube. While it's a small signal tube and these are typically preamp tubes the driver tube can more accurately be thought of as part of the power amp. If the 12AU7 is bad you would get distortion coming through as Beans said.
Ah, thank you for clearing that up for me. I actually don't have another 12au7 around (only a 12ax7 I can grab from a different amp). I just took the amp out of the chassis and checked to make sure all the tubes were seated properly. They seemed to be so I put it back together and will order a 12au7. Hopefully it is just a bad tube.
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