Added an Archon 100 and Stealth Cab to the arsenal but....

[Shawn@PRS]

Great news Shawn! This explanation makes sense as to why with my Strymon Timeline is very quiet in the loop(what I would consider acceptable...can barely tell pedal is on, but doesn't introduce much noticeable noise) while maybe the T-Rex verb pedal I have produces the loud hiss that others are talking about. It's also nice that there is the option to not have to send the amp back, as shipping is costly and of course time without the amp. Hopefully this takes care of the issue for everyone. Thanks!

:top:

 

[rising farce]

Hey Guys,

We are aware of the “hissing” issue that some people are having with the effects loop and we have been actively digging into it.

Let me see if I’m able to explain how the effects loop works:

The signal level comes into the amp at a fairly high level, the level is then dropped before it is sent to the pedals (this is done to keep the signal from being too hot, which might fry some pedals). On the return side (when the signal passes back into the amp), the amp boosts the signal up substantially to drive the phase inverter and power tubes. The level we set for the pedal phase is so low (again to prevent any pedals from being fried) that any noise from the pedal will be magnified when the signal is sent from the pedals back into the amp. If the pedal doesn't add much noise, the amp doesn't have much noise to magnify when sending the signal back to the amp. If the pedal introduces a great deal of noise, then the amp will more significantly magnify that noise in the return line level. This issue has been tested with several pedals; it will not happen with all makes and models of pedals. Actually, this is only happening with a handful of pedals. Please keep in mind that the loop circuitry is always active, even when it is bypassed via the footswitch.


So, if this is making sense at all, we do have a simple modification that basically adjusts the send/return levels so that the amp sends more signal to the pedals, and boosts less on the return side. This will greatly reduce any pedal noise while retaining overall signal level if your particular pedal is causing this issue. The modification is a simple resistor value change, and only requires the replacement of one small component. If you feel comfortable making this change on your own, or if you have a trusted amp tech, we’ll be happy to send you the replacement parts and wiring diagram for free. If you’re uncomfortable making these mods, please contact your dealer so we can make arrangements to have the amp sent back to the factory so the work can be performed (for free). Please keep in mind, this is only necessary if your particular pedal setup is causing an unusable amount of background noise. Please also bear in mind that a small amount of hiss coming from pedals is normal (just as hiss coming from cascading tube gain stages is normal).


Cheers,
Shawn

This is great news. Thanks for the update and information.

A couple of questions from a not-terribly-tech-savvy owner:
1. Is there any way to know which effects will function relatively noiselessly in the Archon loop? For example, will most or all rack effects be comparatively noise-free, whereas most pedals will not?
2. Does the corrective modification you mention affect the tone of the amp in any way, either with the loop engaged or not?

Basically I'm trying to figure out whether it makes more sense for me to simply purchase a different delay unit, or to send the amp in for the mod. I would prefer to take the former route, if possible.

Thanks again.

 

[Shawn@PRS]

This is great news. Thanks for the update and information.

A couple of questions from a not-terribly-tech-savvy owner:
1. Is there any way to know which effects will function relatively noiselessly in the Archon loop? For example, will most or all rack effects be comparatively noise-free, whereas most pedals will not?
2. Does the corrective modification you mention affect the tone of the amp in any way, either with the loop engaged or not?

Most pedals and most rack mounted effects won't cause any problems. Honestly, the only pedal that gave us any trouble (we tested about 20 or so units), only the Boss GT-100 gave us any significant noise.

The effects loop mod will not change the tone in any way.

 

[13bats]

Most pedals and most rack mounted effects won't cause any problems. Honestly, the only pedal that gave us any trouble (we tested about 20 or so units), only the Boss GT-100 gave us any significant noise.

The effects loop mod will not change the tone in any way.

Awesome news!! So Shawn would you say that the New 50 watt head combo and 25 watt head/combo will ship with this new loop mods out of that gate to be prevent issues out of the gate .

 

[stillcenter]

Great to hear Shawn! Perhaps this info regarding the mod can be stickied? I'd be very interested to hear people's experience with the loop after implementing the mod.

 

[Michael B]

This is great to hear, my Archon has been perfect and quiet. Running rack chorus and delay only thru my loop and have no problems with noise, hope this resolves a lot of issues for folks because the Archon is an amazing amp!

 

[alantig]

Thanks for the explanation, Shawn. Always good to know what goes on with the innards of this stuff.

 

[LJD]

Those daisy chained (powered) pedals can't be helping the noise issue. Have you looked into a proper power supply?

 

[vchizzle]

Those daisy chained (powered) pedals can't be helping the noise issue. Have you looked into a proper power supply?

The hiss will occur with a single pedal that's properly powered. Not all pedals cause an issue. I've tried Earthquaker Devices the Depths, Red Witch moon phaser - normally I'd run these in front of the amp but for test purpose the hiss was present. T-Rex Whirly Verb also had the hiss. Strymon timeline and Rocktron intellifex were both fine. All were plugged in one pedal at a time.

I do agree that a voodoo pedal power would clean up the supply, just not likely solve the issue.

 

[rising farce]

I even tried "jumpering" the loop with a short cable last night, just to eliminate all the equipment-based variables, and there was some hiss with that configuration (along with the same, old "pop" from the footswitch when activated). As a result, I'm going to conclude that the mod is necessary to fully eliminate the issue.

 

[iR4lf]

Hey Guys,

We are aware of the “hissing” issue that some people are having with the effects loop and we have been actively digging into it.

Let me see if I’m able to explain how the effects loop works:

The signal level comes into the amp at a fairly high level, the level is then dropped before it is sent to the pedals (this is done to keep the signal from being too hot, which might fry some pedals). On the return side (when the signal passes back into the amp), the amp boosts the signal up substantially to drive the phase inverter and power tubes. The level we set for the pedal phase is so low (again to prevent any pedals from being fried) that any noise from the pedal will be magnified when the signal is sent from the pedals back into the amp. If the pedal doesn't add much noise, the amp doesn't have much noise to magnify when sending the signal back to the amp. If the pedal introduces a great deal of noise, then the amp will more significantly magnify that noise in the return line level. This issue has been tested with several pedals; it will not happen with all makes and models of pedals. Actually, this is only happening with a handful of pedals. Please keep in mind that the loop circuitry is always active, even when it is bypassed via the footswitch.


So, if this is making sense at all, we do have a simple modification that basically adjusts the send/return levels so that the amp sends more signal to the pedals, and boosts less on the return side. This will greatly reduce any pedal noise while retaining overall signal level if your particular pedal is causing this issue. The modification is a simple resistor value change, and only requires the replacement of one small component. If you feel comfortable making this change on your own, or if you have a trusted amp tech, we’ll be happy to send you the replacement parts and wiring diagram for free. If you’re uncomfortable making these mods, please contact your dealer so we can make arrangements to have the amp sent back to the factory so the work can be performed (for free). Please keep in mind, this is only necessary if your particular pedal setup is causing an unusable amount of background noise. Please also bear in mind that a small amount of hiss coming from pedals is normal (just as hiss coming from cascading tube gain stages is normal).


Cheers,
Shawn

Shawn, really thanks for the information. Great to see that you guys take this forum seriously and do not leave us hanging with this problem I will contact PRS Europe to see if they can perform the mod for us here in Europe as I have no amp tech close to me that I would trust to perform the mod!

Are the new Archons modded?

PS: Now I must say: PRS is the king of customer support! Despite the issues we were having Thanks again!

 

[iR4lf]

Just wanted to let you know that my Archon will be shipped to PRS EUROPE next week and they will perform the mod on my amp. They said they have successfully modded a stock Archon and now will mod customer amps. Let's wait and see! Hopefully this will get the issue fixed...

 

[stevan5150]

Shawn , Can I send it back to the Maryland office to get it modded? I purchased mine from sweetwater. If not could you guys provide schematics with the part so I could have my electrical engineer friend do the mod? Do I just call and request the part and diagram?

 

[stevan5150]

I called and left a message for a customer service rep named Matthew , to see if i could get the component and the diagram sent to me....

 

[stevan5150]

Just got my email from Customer service, the emailed me the diagram and are sending out the resistor .

 

[jcha008]

Just got my email from Customer service, the emailed me the diagram and are sending out the resistor .

Awesome! Let us know how this turns out. Hopefully this fixes the issue.

 

[vchizzle]

I got the email as well, unfortunately no time until after this weekend to have the mod done. Hoping for the best and watching this thread in case someone gets it done before I do.

 

[Shawn@PRS]

Are the new Archons modded?

Yes we've made a flying change, so all Archons in production now will automatically get the mod.

Shawn , Can I send it back to the Maryland office to get it modded? I purchased mine from sweetwater. If not could you guys provide schematics with the part so I could have my electrical engineer friend do the mod? Do I just call and request the part and diagram?

If anyone would like to have the mod done at the factory, please contact the dealer you purchased the amp from. They help you make arrangements to have he amp returned to us for the work. Anyone who would like to do the mod locally, please contact customer service. Matt will send out the new capacitor and the diagram.

I got the email as well, unfortunately no time until after this weekend to have the mod done. Hoping for the best and watching this thread in case someone gets it done before I do.

It's a very simple mod. One capacitor gets snipped out and one capacitor is swapped for a different capacitor with a lower value. Almost anyone with a soldering iron should be able to handle it.

 

[andy474x]

PRS amp team are a great crew!

 

[stevan5150]

I am really impressed by their response time to handling this. I just really hope it quiets it down lol I have faith in em!