Express 5:25/10" Hissing Static on Burn Channel

[Nubbs]

Hi All,

Yesterday I played at church and my setup is as follows. Lead guitar is aTaylor Classic Solidbody w/Analysis Plus 10" cable, direct to the amp. Set on 30watt and not too much gain or master, just enough to be heard over the vocals, drums, piano and bass. In clean mode just w little white noise (hiss), but in the overdrive mode a crackling hiss that changes frequency and loudness. There was even a slight popping happening. Now I have heard this before at home but certainly not as pronounced as yesterday. I could not run the amp on the gain side because of it.

I use a grounded orange 15" extension into the amp cord. I also doubled checked the tubes to make sure they were seated properly. Tubes are OEM and have not been changed. The amp is about two years old and second hand to me. It is in mint condition and this has me baffled.

Any ideas what is going on?

Nubbs.

 

[serolf]

Sounds like tube rattle or a microphonic tube. I just had a power tube go out on me and the burn channel went completely lifeless. I called Mesa and they sent replacements. If the amp is two years old then the warranty for tubes is expired (6 months). Just try replacing the preamp tubes with a couple new ones and see if that rectifies your problem. Start with V2 position, first and then V1.

 

[Nubbs]

Great news!!

I have a local authorized repair facility located in Kissimmee, Florida called Hendrix Sound (407-343-6030/http://hendrixsound.com/[email protected]). I called ans soke with Brian who is very knowledgeable about pro audio and anything related to guitar amps. They are authorized for a number of OEMs.

After my conversation with Brian it was clear the best avenue to start with concerning the hiss and static in the red channel was to replace pre-amp tube V1. This is the closest to the input jack. Note: this is very new to me and I was a bit nervous about digging into the amp. We also determined that if this did not clean up the channel then it needed to be taken in for a look see and possible warranty repair.

Fortunately the tube make ALL the difference. In fact, I was just shocked how much better the amp sounded with the change. I never noticed how overall lifeless the amp had become and how much the harmonics had changed. The static and the hiss are all but gone. I only hear a slight bit of "white noise" when the amp is just one and connected to my Taylor Classic Solidbody. But when I say white noise I mean it is hardly noticeable.

Changing the tube was easy and after a few minutes I had it in and on. The tube that Hendrix sent me was a Mesa 12AX7 JJ. Now I am thinking it may be an opportunity to buy all new pre-amps for 65.00.

We are back to better than normal and I have a gig on the 3rd to give it a real run. I'll let you know how it goes.


Nubbs

 

[J.J]

Hey, glad you got it fixed.

I'd highly reccomend that you get a new pair of power tubes while your at it. Those tubes have a much harder life than the pre amp tubes and generally don't last as long. For any important gigs, I keep a spare set of power tubes and a pre amp tube handy just in case.

 

[Nubbs]

Great advice on the tubes. I will be driving to Kissimmee, FL on Friday to pick up the power tubes and an additional pre-amp tube. I know this what I loved about the 5:25 for sound is back and I am a happy clam.

Nubbs

Taylor T-5/Classic Solidbody
Carvin DC-200
Washburn Prairie Song Acoustic
Garrision CE-20 Acoustic
Digitech GNX 4
Sennhieser e609 Instrument Mic