Valve Jr. :(

[Cranium]

I went to the store and finally got my self one, its quite loud for 5w and sounds very nice but now I have a problem! It hums a bit but thats not the biggest problem, the biggest problem is when I hit the low bass notes on the neck pickup (its quite bassy) I hear a little rattling noise, this is quite annoying, does anyone else have this problem, I think Im gonna open the back and make sure nothing is loose but maybe something is wrong with the speaker?

[Tone2TheBone]

No it's probably the tubes rattling in the sockets. Either they're rattling from being vibrated ON the socket or one of the tubes is microphonic. Try grabbing them and moving them around a bit or just take them out and put them back in. You have to figure in a small box there's gonna be a lot of vibration. I found the stock tubes to rattle less than newly replaced ones. I know for sure these guys have fixed this occurence so wait until they post.

[Cranium]

Ok I'll check out the tubes, also what are some good tubes to replace them with? Will I have to bias them or are they fixed?

[Tone2TheBone]

I think J&Js is a good start. You'll get tons of different opinions on tubes here. You might consider all of the options since there are only 2 you'd think of replacing. Try a bunch of different combinations. I'm surprised DVM and Nelskie haven't commented yet. These guys are the VJ pros.

[duhvoodooman***]

Just shoot an e-mail to Eurotubes.com (the e-mail link is on the site) and tell them what you're doing. They will probably recommend a JJ ECC83S for the preamp tube and a JJ EL84 for the power stage. They can give you a graded EL84 for maximum clean headroom, early breakup or something in between, depending on your preference. About $16 + shipping for both tubes, as I recall.

BTW, you do not need a "high gain" ECC83S in the preamp; the normal gain version works great. I mention this because they are out of stock on the high gain version until mid-Sept. or so....

[Nelskie]

I'm surprised DVM and Nelskie haven't commented yet. These guys are the VJ pros.

Not as surprised as I am to hear that I am now being referred to as a Valve Jr. "Pro"!!! But anyways - - -

Cranium, I can relate to your "rattle" issue first-hand. I noticed the exact same thing when I first bought my Valve Jr. As T2TB mentioned, it's most often times a by-product of excess internal cabinet vibration. Even though the Jr. employs a spring-loaded cover for the 12AX7 tube, and a tension-spring type device for the EL84 tube, the outward projection from the rear of the speaker will indeed cause this condtion. And if one (or both) of the tubes is microphonic, this condition could cause it to be more pronounced.

Also, as T2TB and DVM mentioned, new tubes are a good way to start the process of identifying the source of the problem. Even if the tubes are OK, a fresh set of J & J's will improve the sound of your amp significantly. Tone-wise, the stock Sovteks aren't anything to write home about.

The second thing I did to elminate the rattle in my amp was employ the use of silicone ring tube dampers. You'll have to remove the stock tension mechanisms on the tubes to install the rings. As well, if you use these dampers, you won't be able to use the spring-loaded metal cover on the 12AX7 anymore - which I think is a better trade-off anyways. The spring-tensioned mechanism for the EL84 you can still use, though. Overall, I thought these silicone rings did a much better job of preventing the rattling condition than the tension mechanisms did. If you're wondering what tube dampers are - here's a link to the Ebay source where I purchased mine. The photos should be self-explanatory.

http://cgi.ebay.com/8-TUBE-DAMPERS-1...QQcmdZViewItem

You'll also need to make sure you order the correct sizes for the types of tubes you have in the Jr. (12AX7, EL84).

The other thing I did to reduce internal cabinet vibration was use lead tape. Yes, the same stuff golf pros use to weight their clubs. I got the idea from an Ebay auction, and thought it might be worth a try. Anyways - I applied the lead tape (the 1" stuff works the best; cut it into smaller widths if needed) to the amp's control panel enclosure (inside & bottom) & also the speaker chassis, and it helped the rattle situation immensely. The lead also acted as a "deadening" agent, which seemed to take some of the spike off of the amp's high volume tone. At least in my opinion it did. I don't have any real scientific evidence to support that, so whatever you do - take that last statement for face value.

I purchased my roll of lead tape from Golfsmith.com - here's the link:

http://www.golfsmith.com/products/9068

I've attached a couple of photos below to show what areas to apply the tape to. As well, they show what the tube dampers look like installed. These photos are courtesy of the previously mentioned Ebay auction. Good luck!

[Tone2TheBone]

Nelskie - Thats about as professional a response as I've ever seen don't sell yourself short man you are a pro! Great post!

[Nelskie]

Nelskie - Thats about as professional a response as I've ever seen don't sell yourself short man you are a pro! Great post!

*blushing* Awwwww . . . gee whiz. Thanks Tone.