FM9 Problem - Fixed but not what I thought it was

Stratzrus

Roadie
Messages
699
I hadn't used my FM9 for months and decided to fire it up today.

For reasons I don't understand, every preset sounds like the reverb or delay is maxed out and sounds like an amp at the end of a tunnel.

In addition, my clean preset, which I painstakingly dialed in over a period of months and is usually an excellent pristine clean Jazz tone, is now distorting.

What could have caused this and how can I fix it?

I know I'm due for a firmware and preset update and wouldn't mind starting from scratch except I don't want to lose my Studio Clean preset which sadly I didn't back up.

Any thoughts as to how I can get it back to how it was working the last time I used it?
 
@Stratzrus Did you perhaps download an update just before you last switched it off? If you did, then perhaps a "Refresh After New Firmware" would fix it, if you haven't tried that already.
 
@Stratzrus Did you perhaps download an update just before you last switched it off? If you did, then perhaps a "Refresh After New Firmware" would fix it, if you haven't tried that already.

No, I have never connected it to a computer.

Of note, this is through monitoring it using headphones. I can't play it through an amp where I am. That might explain the distortion on the clean preset but doesn't explain the delay/reverb issue.
 
It's probably your headphones @Stratzrus - if they are too low impedance then it could cause audio issues. Do you know what their impedance is?

The FM9 output impedance is 35 Ω, same as the AF3.

Quoting OrganicZed from the FAS forum:

"You want the impedance of your headphones to be about 8x greater than the output impedance of the amplifier they are connected to in order to get proper driver damping. With a near 1:1 match in impedance you will get unusual behavior in the low frequency range and will hear clicking or compression that is not in the original signal."

So if there is compression, it could also make your reverb and delay sound way more prominent.
 
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What about strength of input signal to your signal chain? I'm assuming that this is the exact same guitar you used months ago and nothing has changed there on the input side of things?

Okay. I've thought about this some more and it's probably your headphones @Stratzrus - if they are too low impedence then it could cause audio issues. Do you know what their impedence is?

The FM9 output impedence is 35 Ω, same as the AF3.

No, it's not the same guitar, it's a LP with humbuckers and it has been unplayed for years so it could be dirty pots but that doesn't explain the why the time based effects are now messed up on all presets. I'll try my Strat to see if that's the issue.

It could be the headphones. They're a cheap set of JBLs that I use for watching TV late at night and I have oveloaded them several times but they don't distort when I listen to TV through them.

I did adjust the input signal, it's not in the red. Output knob has to be set higher than usual and still volume is low.
 
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They're a cheap set of JBLs that I use for watching TV late at night and there are times when I have oveloaded them several times but they don't distort when I listen to TV through them

A TV headphone output impedance might only be 2 or 3 Ohms though; so there's a significantly greater potential impedance difference than when connecting the same headphones to the 35 ohms FM9 headphone output.
 
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Also, might be that your headphone is only partially plugged in. That makes it sound all distant and stuff. Or if it’s a cheap headphones with a 3.5mm jack you’re using with a 1/4” adapter, the adapter might be faulty.
 
Also, might be that your headphone is only partially plugged in. That makes it sound all distant and stuff. Or if it’s a cheap headphones with a 3.5mm jack you’re using with a 1/4” adapter, the adapter might be faulty.

It could be the cheap 3.5mm extension cable I'm using. I'll try removing it.
 
Also, might be that your headphone is only partially plugged in. That makes it sound all distant and stuff.

eureka1.jpg


I removed the extension but there was still distortion but after checking I discovered that as you suggested, the cable and headphones were only partially plugged in.

Distortion is gone and time based effects seem normal after a very brief examination. I'll continue to check it out but thanks to everyone for their suggestions.

Truth be told, it's past time that I updated the firmware and started using Axe Edit. I need to get over my fear of bricking the thing.
 
eureka1.jpg


I removed the extension but there was still distortion but after checking I discovered that as you suggested, the cable and headphones were only partially plugged in.

Distortion is gone and time based effects seem normal after a very brief examination. I'll continue to check it out but thanks to everyone for their suggestions.

Truth be told, it's past time that I updated the firmware and started using Axe Edit. I need to get over my fear of bricking the thing.
I knew right away it was a bad headphone cable or poorly connected one. Glad you got it sorted.
 
eureka1.jpg


I removed the extension but there was still distortion but after checking I discovered that as you suggested, the cable and headphones were only partially plugged in.

Distortion is gone and time based effects seem normal after a very brief examination. I'll continue to check it out but thanks to everyone for their suggestions.

Truth be told, it's past time that I updated the firmware and started using Axe Edit. I need to get over my fear of bricking the thing.

It’s been quite stable over the last year, the only update I ever had an issue with was the very first one, after that it’s been smooth sailing on my side and overall for everyone reporting in the update threads. Even the betas have been pretty strong in regards to not shutting down units or having units locking up or anything.
 
Stereo effect’s doing weird …first suspect: phase issue.
volume dropping for weird reasons: phase issues.

check cables, trs adapters etc..
 
As it turns out, the problem isn't what I thought it was.

Once I plugged the headphones in firmly the problem disappeared so I thought it was solved, but when I put the extension cable between the headphones and FM9 it came back.

I looked at the plugs and noticed that the headphone plug had four segments but the plug on the extension cable only had three. The plug on the adapter also only had three.

53189193997_f1daac2946_c.jpg


If anyone knows the details of how this stuff is wired please let me know. But one way or the other I can't use that cable between the phones and adapter.

I wouldn't be using an extension cable but the cord coming from the inexpensive JBL headphones is only about four feet long and that's not long enough to use with the FM9 on the floor.

Out of frustration I ordered a new set of Sony MDR 7506 headphones to replace my old set which I can't currently locate since I moved and were heavily worn and needed to be replaced anyway.

Lesson learned about paying attention to how many segments are on a plug.
 
As it turns out, the problem isn't what I thought it was.

Once I plugged the headphones in firmly the problem disappeared so I thought it was solved, but when I put the extension cable between the headphones and FM9 it came back.

I looked at the plugs and noticed that the headphone plug had four segments but the plug on the extension cable only had three. The plug on the adapter also only had three.

53189193997_f1daac2946_c.jpg


If anyone knows the details of how this stuff is wired please let me know. But one way or the other I can't use that cable between the phones and adapter.

I wouldn't be using an extension cable but the cord coming from the inexpensive JBL headphones is only about four feet long and that's not long enough to use with the FM9 on the floor.

Out of frustration I ordered a new set of Sony MDR 7506 headphones to replace my old set which I can't currently locate since I moved and were heavily worn and needed to be replaced anyway.

Lesson learned about paying attention to how many segments are on a plug.

Out of curiosity, if you pull that 4-segment jack out one segment, does that change anything?
 
That center connector is for headphones with a built in microphone.
I wondered about that.

I ordered these headphones online for a friend who was in the hospital so that she could listen to TV at late night hours so I wasn't really familiar with them. I only used them for the first time with the FM9 because I couldn't find my Sonys.

Never knew they had a mic and never noticed the 4th segment until trying to troubleshoot the source of the problem. I guess that means I can use them with my phone right?
 
As it turns out, the problem isn't what I thought it was.

Once I plugged the headphones in firmly the problem disappeared so I thought it was solved, but when I put the extension cable between the headphones and FM9 it came back.

I looked at the plugs and noticed that the headphone plug had four segments but the plug on the extension cable only had three. The plug on the adapter also only had three.

53189193997_f1daac2946_c.jpg


If anyone knows the details of how this stuff is wired please let me know. But one way or the other I can't use that cable between the phones and adapter.

I wouldn't be using an extension cable but the cord coming from the inexpensive JBL headphones is only about four feet long and that's not long enough to use with the FM9 on the floor.

Out of frustration I ordered a new set of Sony MDR 7506 headphones to replace my old set which I can't currently locate since I moved and were heavily worn and needed to be replaced anyway.

Lesson learned about paying attention to how many segments are on a plug.

While it is true that some devices do not work correctly when a T/R/R/S is plugged into them instead of a T/R/S, in most cases it should work fine.

Your adapter in this picture -- the piece furthest to the right -- is that threaded inside at the top? It looks like the style of adapter which screws onto a specially-made plug. If that's the case, it probably won't work with other plugs except the one it was made to thread onto, because they won't go deep enough inside to properly connect.

That's probably your real issue, and the reason why you were able to force the headphone connector far enough into it to work, but not the extension which has a slightly thicker body on the plug.
 
Out of curiosity, if you pull that 4-segment jack out one segment, does that change anything?
No it doesn't - the tip and Second Ring connect for stereo - and the 3rd & 4th ring connect to ground - question - Why are you using 1/8" plugs instead of 1/4" TRS plugs? - And I know this is dumb - but are you plugged into the Headphone in or the PDL3 in?
 
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