Used to be exdrummer! Looking for help.

[chicks]

Hi folks. Haven't been here in forever and had to re-register.

Don't play guitar or drums much anymore due to severe arthritis in both hands. As such I'm now running live sound and video for a local church.

This morning one of the guitarists plugged his new Alvarez in and got a horrible pulsing sound (kinda like having a flat tire). Even with the preamp turned off and volume off the channel was still pulsing and clipping . Plugged in another guitar and had no problems.

Another player took it home and plugged directly into an acoustic amp and had no problem.

Any suggestions?

[Tamarack]

Hello Chuck!

I am clueless in regard to amplification but it's great to see you back.

[Cosmic Wonder]

What Tam said.

Mike

[epaul]

Guessing time.

I am going to guess that for some reason the cable plug was not seated fully/properly into the guitar's endpin socket. Maybe the player didn't seat it properly, maybe some kind of strange interface issue, or, possibly, aliens.

But, it wasn't the cable or the rehearsal amp as both worked fine with the other guitar. And it wasn't the Alvarez pickup as it worked just fine at the other guy's home. So, somehow, for some reason, the plug wasn't seated right...

Or it was aliens. They are nothing but immature trouble makers, tipping cows and messing with wheat fields. There is no hope in looking to those irresponsible bastards for anything remotely useful.

[epaul]

I should mention that I am a trombone player and, as such, don't use cables or amplification. Nasty, noisy, bothers, the lot of them.

[Dub]

Mar 10, 2024 14:01:03 GMT -5 chicks said:

Hi folks. Haven't been here in forever and had to re-register.

Don't play guitar or drums much anymore due to severe arthritis in both hands. As such I'm now running live sound and video for a local church.

This morning one of the guitarists plugged his new Alvarez in and got a horrible pulsing sound (kinda like having a flat tire). Even with the preamp turned off and volume off the channel was still pulsing and clipping . Plugged in another guitar and had no problems.

Another player took it home and plugged directly into an acoustic amp and had no problem.

Any suggestions?

I like epaul's suggestion.

I have many questions.

1. What is a pulsing sound? A flat tire goes whup-whup-whup if you're driving and psssssssss, if you're not.
2. Are the guitars plugging into DI boxes that are themselves plugged into the house wiring?
3. Did the two guitars use the same guitar cable or did each guitarist have their own cable?
4. Are they using a snake with many inputs or are the house PA system's inputs individually installed as wall outlets or mounted on stair risers?
5. Did the player who took the offending guitar home use the same cable that was used at the church?

There are too many possible variables to answer your question without more detail.

[chicks]

Mar 10, 2024 20:43:02 GMT -5 Dub said:

Mar 10, 2024 14:01:03 GMT -5 chicks said:

Hi folks. Haven't been here in forever and had to re-register.

Don't play guitar or drums much anymore due to severe arthritis in both hands. As such I'm now running live sound and video for a local church.

This morning one of the guitarists plugged his new Alvarez in and got a horrible pulsing sound (kinda like having a flat tire). Even with the preamp turned off and volume off the channel was still pulsing and clipping . Plugged in another guitar and had no problems.

Another player took it home and plugged directly into an acoustic amp and had no problem.

Any suggestions?

I like epaul's suggestion.

I have many questions.

1. What is a pulsing sound? A flat tire goes whup-whup-whup if you're driving and psssssssss, if you're not.
2. Are the guitars plugging into DI boxes that are themselves plugged into the house wiring?
3. Did the two guitars use the same guitar cable or did each guitarist have their own cable?
4. Are they using a snake with many inputs or are the house PA system's inputs individually installed as wall outlets or mounted on stair risers?
5. Did the player who took the offending guitar home use the same cable that was used at the church?

There are too many possible variables to answer your question without more detail.

Yeah, like the whup sound of someone driving on a flat. The guitars run into a DI box then into a 24 channel snake then into the board. 2nd guitar using same cables had no problems.
This is the first time he's used this guitar. The home test didn't use any of the church cables.

[Marty]

Mar 10, 2024 18:24:34 GMT -5 epaul said:

Guessing time.

I am going to guess that for some reason the cable plug was not seated fully/properly into the guitar's endpin socket. Maybe the player didn't seat it properly, maybe some kind of strange interface issue, or, possibly, aliens.

But, it wasn't the cable or the rehearsal amp as both worked fine with the other guitar. And it wasn't the Alvarez pickup as it worked just fine at the other guy's home. So, somehow, for some reason, the plug wasn't seated right...

Or it was aliens. They are nothing but immature trouble makers, tipping cows and messing with wheat fields. There is no hope in looking to those irresponsible bastards for anything remotely useful.

I think Paul nailed it. Cable not fully inserted. 

Many preamp jacks are stereo with the ring connection being the battery ground so it turns on the preamp. If you don't insert the plug all the way in that ground lug makes connection to the hot end of the plug and you get 9v DC in parallel to the amp input.

[chicks]

That may explain it. I'll have him try again Wednesday night. Thanks.

[Dub]

I’ve encountered some cable/guitar combinations that don’t always work well. It the cable has a right-angled connector and the guitar’s input jack is recessed in a certain way, the cable, especially one with RTS wiring, may not connect fully. My Telecaster is that way, I don’t use 90° plugs with it.

[Marty]

Mar 11, 2024 13:13:12 GMT -5 Dub said:

I’ve encountered some cable/guitar combinations that don’t always work well. It the cable has a right-angled connector and the guitar’s input jack is recessed in a certain way, the cable, especially one with RTS wiring, may not connect fully. My Telecaster is that way, I don’t use 90° plugs with it.

Not all cables are the same diameter. Some are 1/4" and some are just over 6mm, same for jacks. So you can have connection problems with the metric ones. Also on acoustics the way the jack is installed is different. It is possible to "short sheet" a jack so the plug won't insert all the way.

[Marshall]

Mar 11, 2024 21:07:38 GMT -5 Marty said:

it is possible to "short sheet" a jack so the plug won't insert all the way.

Yes that's a possibility too. But it's not easy to correct. The person can remove their strap and the outer endpin cover on the endpin. There's still a small nut and washer that hold the endpin to the guitar. If you plug a 1/4" cable into that and an amp and the problem goes away, you know the endpin was not installed properly and needs to extend out further.

But try this first:
Or more likely the endpin cover screw has unscrewed a bit (constantly playing with the strap can cause that screwed piece to loosen). He should try tightening that up. If it's too loose, it will keep the 1/4" cable from penetrating enough to make proper contact with the pickup endpin.

[millring]

Mar 11, 2024 8:38:40 GMT -5 chicks said:

the whup sound

was it a big whup?

[millring]

whup.

there it is.