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

Just curious, is it still noisy going into the front of the amp? Just asking because both of my Mesa heads (recto and mark) are both noisy through effect loop and fine through the front
 
I am running an Archon 100 W through a Big Mouth Stealth Cab with a Boss GT-100. This is my second head. Sent the first one back for noise on both channels. Picked up the second one on Saturday, noise issue in the channels solved, plug in my gt100 into the effects loop and surprise surprise, NOISE,NOISE NOISE. Looking for suggestions. Drop down to the Archon 50/25, live with it, the gt 100 works fine in front of the amp, maybe a Custom 50 has all the bugs worked out. What is the best way to contact PRS on these types of issues?
 
Guys, thanks for sharing your opinions. Really, I can't believe that this issue is marked as "normal behavior" by the PRS amp department...We all know it is not! And buying different equipment that may work for a specific amp is not a solution, at least for me. With an amp like this (regarding price and prestige of the company), you should only accept perfection. So I have sent yet another mail to PRS...Let's wait and see. Maybe we all should raise their awareness to this issue and all send them mails?
 
I am running an Archon 100 W through a Big Mouth Stealth Cab with a Boss GT-100. This is my second head. Sent the first one back for noise on both channels. Picked up the second one on Saturday, noise issue in the channels solved, plug in my gt100 into the effects loop and surprise surprise, NOISE,NOISE NOISE. Looking for suggestions. Drop down to the Archon 50/25, live with it, the gt 100 works fine in front of the amp, maybe a Custom 50 has all the bugs worked out. What is the best way to contact PRS on these types of issues?

Well, it seems like the effect loop is the issue...Putting effects in front of the amp seems to not cause any issues. Best way is to contact them is via their customer service if you are in the US or your local distributor everywhere else...
 
iR4lf - I feel everyone's pain, I was an early adopter of this amp when it first came out, and immediately discovered the issues. I have done my due diligence in trying to get help from PRS but, their answer is that this is normal and to be expected.

Their main customer service rep is Matt, From what I have read, his responses to Archon amps owners have been consistent about this being a normal. It is something you may want to tell Paul himself. Paul is often making guest appearances at some of his larger dealers, and I'm sure he would listen to anyone of our feedback. But I think the cold hard fact is that this amp has tradeoffs. All of us who love PRS equipment are shocked as we thought PRS does not compromise. No way am I making an excuse for them as I think it is shameful, and the reason why I no longer own an Archon.

I think it will truly be telling if the Archon 50 has the effects loop issue.

Please keep up the fight, I will be rooting all of you guys on!!
 
For someone like myself, it has not been a big issue because I run a wet/dry rig and don't use the loop. My time based effects(delay & verb) that absolutely have to be in the loop on the high gain channel are in between a Suhr ISO box and a tube power amp. I also have a 2nd Archon a home now, so when I get more time I'll try to experiment more with what works and what doesn't. It seems by all accounts so far, line level fx like rack effects seem to work better. Bottom line is not many people run rack fx anymore and that seems to be where the problem lies for "the common user". It certainly seems like an oversight by PRS. As I said in another thread, I don't remember hearin of issues with the loop in the custom 50/100 and am curious if it uses a different type of loop. I hate to see this amp get a bad rap because of the issue, as it is a great amp in all other respects. We will see what transpires I guess.
 
Hey all, I just registered an account here to provide support to y'all in getting this fixed or at least properly recognized by PRS. I bought an Archon off a forum member and have experienced terrible hiss/hum when the effects loop was on. I also get radio interference when the loop is on. Totally unusable. I've sent the amp back to PRS via Matt and we'll see what their response is. Based on everything I've read so far, I'm not optimistic that they'll do much of value for me and my amp :(

This really is a huge bummer because the amp sounds fantastic. I recently bought my first PRS guitar and was blown away by the fit, finish, and attention to detail. Not so with these amps, it seems...

Btw, the only thing that kept the loop noise level even remotely 'quiet' was to jump the loop with a 3 inch cable. Putting any pedal, even a Strymon, in the loop caused unusable amounts of noise and RFI (possibly this is due to the fact that the cables were longer than 3 inches).
 
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The Archon is such a good amp, the loop noise is a real shame.

I just wish PRS could at least admit there's an issue. It seems lots of people's concerns have been disregarded or deemed insignificant.

To imply it's more user error than design flaw is off-putting and doesn't make you feel warm and fuzzy about your investment. Like Steve Jobs saying people were holding their phones wrong.
 
Out of curiosity, has anyone tried using a line-level shifter, like an Ebtech? It's not an ideal solution, obviously (I typically don't like chasing inherent problems by deploying more gear), but it might save some of the pedals-in-the-loop folks from having to sell off their amps.
 
Out of curiosity, has anyone tried using a line-level shifter, like an Ebtech? It's not an ideal solution, obviously (I typically don't like chasing inherent problems by deploying more gear), but it might save some of the pedals-in-the-loop folks from having to sell off their amps.
I had thought about ordering one just to see if it helps.
 
Egnater has a huge problem with loops and this is what fixed it ..

I also think FWIW that JJ preamps tubes go bad fast so changing out the preamp tubes especially the one in PI and loop may be beneficial
 
Well, they are pretty inexpensive so it's probably worth a shot. I thought I heard the loop was made to be used with pedals, but it seems line level devices work better, so maybe the Ebtech thing would help. Cheap fix if it does. I looked on PRS site and the Archon loop and the 2 ch CU50 loop are both series loops. The 50 has send/return level knobs. Not sure if anything else is different. Going to start a thread about the 50 loop.
 
Egnater has a huge problem with loops and this is what fixed it ..

I also think FWIW that JJ preamps tubes go bad fast so changing out the preamp tubes especially the one in PI and loop may be beneficial


So let's collect the options...The Ebtech Line-Level Switcher seems like a good idea. Maybe the Archon produces a "hot" send level signal that causes problems with the pedals. Any chance someone can try that?
Maybe changing preamp tubes might help, well I got no spare tubes here...Let's see what that brings to the table if anyone can try that...

I have sent another mail to my local distributor and he is aware of the problem but said that the guys at PRS still think this is normal and that there will be no modding or help from their side. It seems like once the amp is designed they are not willing to change it.
But he has a tube amp technician that will take a look at the Archon effects loop issue. Don't know what to expect, but I'll keep you posted guys...
 
My recording studio experience tells me that line level vs instrument level differences can often cause problems with noise, hiss, hums and buzzes.

I had a box that changed levels, but I recently tested it, and hadn't used it in so long that it no longer works. If I could have gotten it going, I'd have sent it to one of you to test with your amps.

In fact, I had this very problem with the loop on my old Tremoverb back in the rack days...it worked fine with line level rack gear, but was noisy with pedal gear.

Ya know, the Radial SGI might be a solution as an alternative to the Ebtech. And the reason I mention it is that the Ebtech isn't really an instrument-level to line-level shifter, it's really a consumer to pro-level shifter. Guitar instrument level output is much lower than consumer electronics level.

The SGI is apparently designed specifically for guitar levels, and it's not a passive device, which might be a good thing. On the other hand, you'd need XLR>>TR cables, etc, so that adds even more to the expense. For a pro solution, however, it might be worth talking to a tech person at Radial, because they do mention going back and forth from pedalboard to amp effects loops as an application on their site.

My solution back in the 90s was to simply use an Eventide H3000 rack box in my amp's loop.
 
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So let's collect the options...The Ebtech Line-Level Switcher seems like a good idea. Maybe the Archon produces a "hot" send level signal that causes problems with the pedals. Any chance someone can try that?
Maybe changing preamp tubes might help, well I got no spare tubes here...Let's see what that brings to the table if anyone can try that...

I have sent another mail to my local distributor and he is aware of the problem but said that the guys at PRS still think this is normal and that there will be no modding or help from their side. It seems like once the amp is designed they are not willing to change it.
But he has a tube amp technician that will take a look at the Archon effects loop issue. Don't know what to expect, but I'll keep you posted guys...

I'll be interested to see what the tech says.

Just to reiterate, changing the PI and/or loop tubes does not help with the noise; I tried. Experimenting with preamp-tube swaps for the purpose of effecting tonal changes, on the other hand, can be a rewarding exercise.
 
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
 
The loop in my SE amp works great - the amp does hiss a good bit on the gain channel, but seems to be independent of the loop. Strange that the Archon has that issue, I have to believe for how well the other PRS amp loops work, it must be a pedal issue, like Shawn said. Don't see why they would change the circuitry if it works so well in the other amps.

Has anyone tried a 4-cable type noise gate, like the Decimator G String or MXR Noise Clamp? I have a Noise Clamp in my loop and it works like a charm to cut the hiss when I'm not playing. If anyone's interested in how to set one up that way, I'd be happy to share.
 
Has anyone tried a 4-cable type noise gate, like the Decimator G String or MXR Noise Clamp? I have a Noise Clamp in my loop and it works like a charm to cut the hiss when I'm not playing. If anyone's interested in how to set one up that way, I'd be happy to share.

Does not work.
 
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
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!
 
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