Rocker 32 Scratchy Sound

[Speegman]

I bought a new Rocker 32 and have recently started experiencing a scratchy sound on the clean channel when I power up the amp. After a about a minute the scratchiness goes away. It sounds like kinda like radio static. Anyone experiencing this?

Also, to get the dirty channel to any sort distortion the volume has to be fairly significant. This volume is too loud for home use. I do have a Caitlin Bread dirty little secret to get a good overdriven tone but I was hopping to use only the dirty channel.
Thanks for any feedback!

[Jondog]

Symptom of bad tubes

[Speegman]

That's a bummer! I've only played the amp about 15 times since purchasing it earlier this year. I got it from Sweetwater and I'll get them to take a look at it. I don't have the knowledge to change the tubes myself.

[PBA]

...I got it from Sweetwater and I'll get them to take a look at it. I don't have the knowledge to change the tubes myself.

Firstly - yes get Sweetwater to fix the problem, it after all new equipment and should be expected to function correctly.

Secondly - Do disrespect intended. Do get the knowledge. Go watch youtube videos, read online articles whatever it takes. If you own a valve/tube amp you really do need the small amount of knowledge it takes to swap out the valves/tubes.

I would also recommend buying some replacements so that you are ready for the next time you encounter a valve/tube problem.

You will need to check but I think you would need a matched pair of EL84 power valves.tubes and one or more 12AX7 pre-amp valve/tube. That would be the minimum. I suspect most of us will have more than one complete set of valves/tubes ready and waiting.

Oh - also get a packet of the right type of HT fuses. The HT fuse will inevitably blow at some point.

Good luck - it's generally worth it!

[Rlw59]

Tubes usually last a fairly long time, but they can go bad suddenly at any time. Rarely, a brand new tube can be bad before you take it out of the box.

Your amp is cathode biased so you don't need to do any electrical adjustments when replacing tubes. Tubes plug into sockets. Just unplug the old tubes, line up the pins on the new tubes, plug them in. (There are some minor fine points but in essence it's that simple.)

Having said that, I've known people who have no mechanical aptitude whatsoever. I've got a neighbor who can't hook up a dvd player to her tv.

There's nothing wrong with being like that. There are lots of things I've tried really hard to learn how to do but still can't do.

But if you can't change tubes, a tube amp will leave you stranded sometimes, and will cost you time and money to get it back up and running.

[Speegman]

Thanks all for the response - I'll give Sweetwater a call and look into changing the tubes. I can usually follow instructions.

Regarding lowering the speaker volume - can a power attenuator be installed on this amp?
Best regards!

[Rlw59]

Attenuators can be used with combo amps. It can be a little awkward because the speaker wires tend to be short, but it can be done.

Shouldn't need to use an attenuator though. Your gain, master, and selectable power levels should let you get tons of distortion at low volumes.

Your needing to crank it to get distortion is most likely due to a weak preamp tube.

[Rlw59]

Oh, the Rocker 32 has stereo power amps -- each speaker has its own power amp.

So you'd need to use two attenuators.

[Speegman]

Oh, the Rocker 32 has stereo power amps -- each speaker has its own power amp.

So you'd need to use two attenuators.

Update: I put in Tung Sol's for both preamp tubes and the scratchiness is gone. The amp sounds great and I can get nice gain at low volume. The clean channel is now breaking up as It should. Very happy as this amp cost way too much money to not sound good. Based on what I'm hearing now, the JJ's that were originally in the amp weren't really producing a good tone.

[Rlw59]

JJ's are a little darker sounding than most tubes, but a lot of people love them.

Rough handling during shipping can knock the internal parts of tubes out of alignment. And like most electronic components, sometimes tubes suddenly go bad for no apparent reason (usually either when they're pretty new or pretty old -- once they make it through the first month or so they're likely to last a good long while).

Good JJ's sound much better than defective JJ's. Since you like the Tung Sol's there's no reason to ever go back to JJ's, but don't assume they all sound like that.

[Speegman]

JJ's are a little darker sounding than most tubes, but a lot of people love them.

Rough handling during shipping can knock the internal parts of tubes out of alignment. And like most electronic components, sometimes tubes suddenly go bad for no apparent reason (usually either when they're pretty new or pretty old -- once they make it through the first month or so they're likely to last a good long while).

Good JJ's sound much better than defective JJ's. Since you like the Tung Sol's there's no reason to ever go back to JJ's, but don't assume they all sound like that.

There are good reviews on JJ's and I am open to using them in the future. I have have Groove tubes in my Fender Super Champ X2 and they sound incredible. This was a good opportunity to try something different and Guitar Center had them in stock - I really didn't want to mail order this time.