4CM again - lot of hiss and unity gain question

Owczar

Owczar

Member
Hello!

I'm trying to integrate my axe with tube amp - I've got hum buster cables - they help a lot with hum, but still there is serious hiss...
I've got Cornford MK50h - it's not high gain monster, it's dead quiet when i plug guitar straight in, or with axe just in loop, but in 4CM - unusable.
I've found info about some kind of output2 mod which removes hiss, also that FAS made this mod as standard feature some time ago - is it true?
I've bought my axe in july 2013 in g66, how can I check if my axe have mod onboard?

Another question - what's about unity gain procedure? I turned up Output 1 and Output 2 knobs - so in theory it should maintain the same volume?
With amp it's ALOT louder, I've got to turn Output 1 knob to about 12 o'clock for similar volume to guitar and amp only.

Thanks in advance,
Cheers!
 
What Axe FX do you have? There were issues with the earlier models & this has now been resolved with the XL. I run 4CM with my Friedman amp & it's dead quiet!
 
Owczar said:
I've found info about some kind of output2 mod which removes hiss, also that FAS made this mod as standard feature some time ago - is it true?
I've bought my axe in july 2013 in g66, how can I check if my axe have mod onboard?
Click to expand...

yes that is true. Not sure exactly when the mod became a standard feature though. I think units from your date should have the mod already. I have a first gen Axe fx (without mod) and also experience a lot of hiss when using pedals (no amp) in the fx loop. That's why I stopped using it all together.
See also this topic: http://forum.fractalaudio.com/axe-f...g-effect-pedal-behind-axe-fx.html#post1101838
 
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Owczar said:
Hello!

I'm trying to integrate my axe with tube amp - I've got hum buster cables - they help a lot with hum, but still there is serious hiss...
I've got Cornford MK50h - it's not high gain monster, it's dead quiet when i plug guitar straight in, or with axe just in loop, but in 4CM - unusable.
I've found info about some kind of output2 mod which removes hiss, also that FAS made this mod as standard feature some time ago - is it true?
I've bought my axe in july 2013 in g66, how can I check if my axe have mod onboard?

Another question - what's about unity gain procedure? I turned up Output 1 and Output 2 knobs - so in theory it should maintain the same volume?
With amp it's ALOT louder, I've got to turn Output 1 knob to about 12 o'clock for similar volume to guitar and amp only.

Thanks in advance,
Cheers!
Click to expand...

Less hiss with Output 2 Mod on Axe II (all model i tried) but still too much to be usable with high gain ... I ll try today with the XL (i bought recently) and come back to you
Output 1 knob to about 12 o'clock for similar volume is normal , output 2 must be maxed
 
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Make sure that you set Output 2 Boost/Pad in the I/O menu at 18dB - that increases the S/N ratio for me enough to reach an useable level.

Mike
 
Hello!

I'm a Cornford Mk50h II user and i'm very interested to buy an axe fx II mark II as you.

Do you found any cause and solution at your problem?
 
Can anyone confirm that the new FX-8, which is designed for the 4cm, will have less hiss and hum than the current axe fx 2 -xl?

I would be willing to buy the fx-8 and use it with my tube amps, and reserve the axe fx 2- xl for foh/recording applications. This is of course assuming it has less noise than the axe fx -2 xl in the 4cm setup.
 
gibsonash said:
Less hiss with Output 2 Mod on Axe II (all model i tried) but still too much to be usable with high gain ... I ll try today with the XL (i bought recently) and come back to you
Output 1 knob to about 12 o'clock for similar volume is normal , output 2 must be maxed
Click to expand...

Both output knobs must be set to maximum in 4CM. If you don't you will get lots of hiss.
 
FractalAudio said:
Both output knobs must be set to maximum in 4CM. If you don't you will get lots of hiss.
Click to expand...

But then i have more overall volume and a little different sound - why more volume if this mode is called "unity gain"?

I've got Mark II, Output 2 boost/pad set at 9db (if I remember correctly) - output clipping on higher setting.
With noise gate activated after fx loop block it works with overdriven tones, but on quieter parts with "cleaned" sounds (I play alot with volume pot) hiss in background is really annoying :(
 
I bought my Axe-Fx II Mark I in March 2012 and had the Output 2 Mod done last year and it made 99% off the hiss go away with a Mesa Boogie TriAxis and Marshall JCM 2000 DSL100. The hiss sounded like white noise and wasn't dynamic like the noise you get from lights or old computer screens.
 
Owczar said:
But then i have more overall volume and a little different sound - why more volume if this mode is called "unity gain"?
I've got Mark II, Output 2 boost/pad set at 9db (if I remember correctly) - output clipping on higher setting.
With noise gate activated after fx loop block it works with overdriven tones, but on quieter parts with "cleaned" sounds (I play alot with volume pot) hiss in background is really annoying :(
Click to expand...

At what value is your input 2 (in IO)? I've got mine at 9 oc (1/4) to match the signal levels. Both output knobs 1 and 2 at max BTW
 
I thought it's better to set input levels as high as possible (touching red leds)? With input 2 set about 17% ( 9 o'clock ) and both output knobs cranked there is similar volume, but hiss is still audible :(
 
Sorry to revive this thread but I'm having a similar issue, albeit the complete opposite haha. This is a new adventure for me, I've always used my Axe as a standalone unit, never in the loop of an amp. Did a lot of reading around and I'm getting this issue that I couldn't find anything on:

I've got a Jet City amp that I just got hold of - trying out running the Axe in 4cm with it. Got an absolute load of noise, even with hum busters, but I've now hooked up an Eb Tech Hum eliminator into the mix and it is much much better.

However, the overall volume is now quieter than when using the amp on its own (guitar into head) - and I also have less gain - it kinda sounds like I've rolled off the volume on the guitar a touch.

With my Gibson, instrument input 1 level is set about 25%, input 2 set at 20% (any more and I get some serious red light action). My output 1 level is down by about -5db too, again any more and I get some hideous audible digital clipping. Both my output 1 and 2 knobs are up to the max (\m/)

My connections are as follows:

Axe Out 1 -- TRS cable -- Eb Tech Channel 2 input -- Eb Tech Channel 2 Output -- Instrument Cable -- Amp Fx Return

Axe Out 2 -- TRS Cable -- Eb Tech Channel 1 input -- Eb Tech Channel 1 Output -- Instrument Cable -- Amp Input

Axe In 2 -- Humbuster cable -- Amp Fx Send

Again, sorry to revive an old thread but I thought my issue was similar and didn't wanna clutter up stuff with a new thread :) Thanks in advance!
 
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Are you sure you described those connections correctly? Out 1 & Out 2 are opposite from the correct 4CM. Your listed connections would just go through the first group of blocks, to Output 2 via FX Loop, to your amp's FX return.

Also state what your Out 1 & Out 2 boost/pad values are. This (the Out 1 value to be exact, but it's good to have complete info) may or may not be the cause of Out 1 clipping with lower volume than you'd otherwise have.
 
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