Popping noise

[MassiveBoogers]

Hey guys. Since I bought my Dual Rectifier less than a year ago, there seems to have always been a strange pop when switching from Channel 1 (clean) or 3 (heavy) over to Channel 2 (dirty). It's only Channel 2 that pops when I step on the button and seems to be loudest when switching from Channel 3. Does anyone know what's going on with it?

 

[espboogie123]

I've owned two new boogies, a dual rec solo and roadster. Both pop when entering the orange channel when just fired up. It goes away when cycling through the channel couple times. I believe its normal with these boogies. If it constantly pops, rather than just the first couple times from firing it up, then there's something wrong.

 

[plapnab]

Mine used to do that too. When I'd start up I'd just cycle through the channels and it would do it the first time I'd go to channel Red...then wouldn't do it again unless I turned the amp off and back on again. After a while it just stopped doing it all together...that as well as a variety of other wierd, quirky things. I swear, these amps are built like a tank but they do have a mind of their own it seems. :?

 

[mylo]

I read somewhere to cycle through the channels (ending with hitting the orange channel the second time through) while amp is on standby prevents "the pop". I have started doing this and it has worked for me. Every now and then I still get a small pop when switching to green for the first time.

 

[MesaENGR412]

I have read that the pop comes from the LDRs that are used in the switching system. Sometimes they build up a static charge, and this is released when they are switched back and forth, and after while the charge has dissipated and that is why the pop goes away. I think I read that on here somewhere. Could be wrong, but, the pop seems to be normal on Rectos, and it goes away for me free a first couple cycles ( I also do the cycle through while on stand by) and when played with a band you don't notice it at all.

-AJH

 

[mikey383]

I have read that the pop comes from the LDRs that are used in the switching system. Sometimes they build up a static charge, and this is released when they are switched back and forth, and after while the charge has dissipated and that is why the pop goes away. I think I read that on here somewhere. Could be wrong, but, the pop seems to be normal on Rectos, and it goes away for me free a first couple cycles ( I also do the cycle through while on stand by) and when played with a band you don't notice it at all.

-AJH

The 3 channel Rectos don't use LDRs, they use relays instead. The pop you hear is the contacts making, well, contact.

I think I read there's a fix to it, but it involves much work and money, so the simplest solution is to do as has been said....cycle through the channels with the amp in standby.

 

[msi]

The newer amps (Since around the three channel solo heads) use relays. A relay is a switch and if the contacts of the relays share different voltages they can cause an audible pop. It's the same premise as the noise you hear when plugging a cable in with the amp on. The rectifiers have a circuit to reduce the amount of pop the amp causes by using a quirk of the relays. When the relays go from a charged state to an uncharged state there is a little rush of voltage in the switching circuit. This is routed to the mute circuit I mentioned earlier and briefly mutes the signal and removes any audible pop. The relays need to go from a charged state to an uncharged state though, which is why flipping through the channels usually resolves the issue. The mute circuit isn't perfect and sometime a pop will get through. If the pop is loud though and happens every time you switch a channel you may have an issue.

I remember calling mesa about this and they felt that as the pop is usually inaudible when playing with a band it wasn't something I should be very worried about. I generally agree with that explanation.