VP4 vs FM3

Tons and tons of reports of the FM3 not being adequate enough in 4-cable-method. Enough to scare me away in the past. I'm sure I read that the secret sauce isn't the same in FM3, so maybe that is the reason why?
I had hiss-issue with AX8 in 4CM. I try FM3 in 4CM with a couple of amp, way less hiss. But I prefer to use FM3 in front of an amp or even better in the amp fx return, with the amp block on and cabs off. No hiss/hum/quality-issue at all.
 
Of course it has relevance.

If the input1 doesn't have the secret sauce, and thus has a higher noise floor, then the entire system noise-floor level is necessarily higher, because that noise at the input is amplified by your real amplifiers front end, looped back around through the effects loop back into the FM3 into another input that won't have secret sauce, and then back into the amps return. You've got two points of digitization there that can be sources of noise. Any noise upstream from the amplifier is going to make the system noisier.

Semi-related, but I did a bunch of measurements on noise in 2022, and this is how a bunch of my stuff came out:
View attachment 146861

These aren't 4-cable-method measurements. So any of this gear in a 4-cable-method setup - or more traditional effects out front and in the loop type setup - are going to be noisier. To what degree, it is hard to say. But clearly, noise floor is something that raises (sometimes very significantly) when you introduce AD/DA conversion.

Recently I compared the Quad Cortex, Helix, and Axe3 in front of an amp too. And that is exactly the ranking - Quad Cortex is the loudest, and definitely requires some kind of noise gate when hitting the front of a high-gain channel, Helix is the middle child, and Axe3 is the quietest; for my amp I have to use the boost/pad feature at 18dB.

Now I've never heard the FM3, so I can't comment too much. All I can say is, I've seen a lot of reports about it being noisy and finnicky to setup in 4-cable-method. I believe Cliff has even said that it isn't truly designed for that purpose, and that people are better off using the FM9 or Axe3... or now... VP4.

I could be wrong on that last point, but it is my recollection at the moment.
Point well taken on noise prior to the connection between FM3 and external amp input, but it seems to me that if this were the main cause it would be more consistent (some people don't have the issue, some more than others, and a lot of those reports sound beyond the "hiss" I hear when I test for noise floor in my amps in 4CM). With my Ax3, across the 5 or 6 amps I've 4CM'd through it, about 1/2 have had noise/hum issues I could not figure out. Currently, of the 2 tube amps I use, the higher gain Blackstar is dead quiet compared to the lesser gainy and brighter Hughes Kettner which has some hum I have to use an isolator to get rid of (strange - I'd've expected the opposite). So the point I was making above is that, from my experience, different tube amps behave differently in 4CM - I wish I knew the exact mechanisms at play so I'd know, when considering an amp purchase, whether or not it would work well in 4CM.

Also I'm not sure everyone is defining 4CM related noise in the same way (not to mention peoples' widely varying perceptions of what's "noisy"). For me, it's the difference between guitar straight in with guitar volume all the way down, and 4CM with guitar volume all the way down (gates off and using a confirmed unity gain loop, a confirmed quiet + properly shielded guitar, and humbuster cabling for 4CM). And, I'm checking for noise in 4CM that's present regarless of amp channel or settlngs. Though I can detect the additional hiss inherent in 4CM I don't count it as a problem because I always expect a certain amount of that with 4CM - but ya, if noise floor is waay worse on FM3, I guess that's definitely an issue with FM3 compared to Ax3 - just does not seem to be any definite confirmation that FM3's input causes consistently bad external amp connection, and peoples' reported experiences I read does not seem to be consistent enough to point to that as the main factor at play. But I have often wondered why the FM3's input setup is designed differently than FM9/Ax3 - seems like an odd choice to me - having one unit's input working differently than the others (on another related note, I'd love to know what's different about VP4 that allows it to get the humbuster benefit without the use of humbusters).
 
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I didn't get a chance to respond to your other post as the thread was locked due to the product release.

My noise issues are not to do with ground loops - it is hiss.
I can reduce this by setting the boost/pad on output 2 but then this clips the output.
yes - using the output boost/pad feature reduces headroom for digital output clipping (at least it does in my Ax3), so, though useful to minimize noise in 4CM configs, one has to keep an eye out for the tradeoff in digital output clipping headroom when using the boost/pad feature on output. I set it to 12 currently, which gives me an audible benefit in reduced 4CM noise while maintaining headroom on digital output clipping even if I engage a boost set up inside Axfx to boost the input of the 4CM'd amp.
 
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yes - using the output boost/pad feature reduces headroom for digital output clipping (at least it does in my Ax3), so, though useful to minimize noise in 4CM configs, one has to keep an eye out for the tradeoff in digital output clipping headroom when using the boost/pad feature on output. I set it to 12 currently, which gives me an audible benefit in reduced 4CM noise while maintaining headroom on digital output clipping even if I engage a boost I may have set up inside Axfx to boost the input of the 4CM'd amp.
the only other thing I may try is to see if a reamp box would work inbetween the output 2 of the fractal ant the input of the preamp
 
the only other thing I may try is to see if a reamp box would work inbetween the output 2 of the fractal ant the input of the preamp
Putting this isolator box just in front of the problem amp's input helped in my case - but its a crapshoot on what will work, and imo a bandaid to some mysterious underlying issue that happens with some amps in 4CM and not others.
 
Of course it has relevance.

If the input1 doesn't have the secret sauce, and thus has a higher noise floor, then the entire system noise-floor level is necessarily higher, because that noise at the input is amplified by your real amplifiers front end, looped back around through the effects loop back into the FM3 into another input that won't have secret sauce, and then back into the amps return. You've got two points of digitization there that can be sources of noise. Any noise upstream from the amplifier is going to make the system noisier.

Semi-related, but I did a bunch of measurements on noise in 2022, and this is how a bunch of my stuff came out:
View attachment 146861

These aren't 4-cable-method measurements. So any of this gear in a 4-cable-method setup - or more traditional effects out front and in the loop type setup - are going to be noisier. To what degree, it is hard to say. But clearly, noise floor is something that raises (sometimes very significantly) when you introduce AD/DA conversion.

Recently I compared the Quad Cortex, Helix, and Axe3 in front of an amp too. And that is exactly the ranking - Quad Cortex is the loudest, and definitely requires some kind of noise gate when hitting the front of a high-gain channel, Helix is the middle child, and Axe3 is the quietest; for my amp I have to use the boost/pad feature at 18dB.

Now I've never heard the FM3, so I can't comment too much. All I can say is, I've seen a lot of reports about it being noisy and finnicky to setup in 4-cable-method. I believe Cliff has even said that it isn't truly designed for that purpose, and that people are better off using the FM9 or Axe3... or now... VP4.

I could be wrong on that last point, but it is my recollection at the moment.
Input 1 on the FM3 has the secret sauce just like the others (it's a limiter and emphasis/de-emphasis noise reduction as I understand it?), just not the variable impedance to mimic some fuzz pedals. Input two is line level, so make sure your amp's master or send level is correct.

Output two should be sending whatever the amp's FX return desires, adjust with the block level.

A relatively noisy guitar goes into a relatively quiet digital device, then the signal goes into a noisy tube preamp, then the preamp's noise is again returned to the relatively quiet digital device, and finally sent to a noisy tube power section.

So, the Input two Noise Gate is your best friend, and using Input one's NG in addition can help as well depending on the pups and environment. IME with a large number different tube preamps it's been fine, though I'm not dealing with full tube amp's FX Loops either, and these can of course be a big variable depending on the amp's designer.

So, which amp(s)?
 
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I'm not going to search for it so maybe @Admin M@ or @FractalAudio could chime in to comment on the VP's I/O optimization for use with an amp in 4CM vs the other products.

I've been asking this question both in forum threads and through PMs to @Admin M@ and no one has answered me yet .... Maybe you'll have better luck !?!

Given that humbusters aren't needed ..., it makes me wonder if Cliff came up w/ some sort of 'new' magic that improves on what's already pretty damn great ?
 
I have also read several times that the analog path of the FM3 differs from the other products. I would be particularly interested to know whether this also affects the main input (which, at least according to Wiki, should have the same secret sauce as the other devices) or only the other inputs and outputs, so that there is only a difference when using the 4-cable method.
 
Could someone cite an actual hard reference to these statements being read "somewhere" that the FM3 is not designed for 4CM the way the other units are
 
Could someone cite an actual hard reference to these statements being read "somewhere" that the FM3 is not designed for 4CM the way the other units are
I have not used the VP4, but I suspect it works similar to how the FM3 works with 4CM. Some amps will be noisy and some will be relatively quiet. Same with Line 6 gear, and other pedals
 
Could someone cite an actual hard reference to these statements being read "somewhere" that the FM3 is not designed for 4CM the way the other units are

I'm not doing an exhaustive search. Here's a few from users:
https://forum.fractalaudio.com/threads/new-fractal-product-coming.207160/page-23#post-2588557
https://forum.fractalaudio.com/thre...rm-factor-im-begging-you.184652/#post-2298534
https://forum.fractalaudio.com/threads/fractal-4cm-club.173106/page-3#post-2140998
https://forum.fractalaudio.com/threads/fractal-4cm-club.173106/page-3#post-2159674
https://forum.fractalaudio.com/threads/best-add-ons-for-your-fm9.182461/page-3#post-2246196

There are multiple threads about noise and hiss with the FM3 and 4CM. I have had mixed results myself when using the FM3 in 4CM.

Here's a post from @FractalAudio discussing the 4CM processing in the FM9.
https://forum.fractalaudio.com/thre...eler-fx-processor.176122/page-25#post-2138853

Here's a post from @Admin M@ confirming that there are some differences between the FM3 and FM9:
https://forum.fractalaudio.com/thre...-curious-about-something.198902/#post-2474704

It would be nice to get a statement from FAS regarding the circuitry of the FM3, FM9, AxeFX III, and VP4 with regards to their optimization for 4CM. A little clarity on that may help some users determine which unit is best for their use case.
 
The VP4 looks like an excellent multi-effects unit, and if I used tube amps I definitely would buy one. However, if like me, you use the FM3, I don't see the value to replacing it with the VP4. The FM3 is more powerful, more versatile, and more flexible. It has amps and cabs. It's very compact. I typically run it into the front of a Quilter Tone Block 202 and speaker cabinet on the Quilter's FRFR setting, and using the FM3's amps, cabs and effects. If the FM3 were to fail, I have the Quilter as a stand-alone back-up amp with reverb. If the Quilter were to fail, I would be able to run the FM3 into a mixer / FOH / PA.
 
i will but vp4 to include it in my pedalboard with quad cortex-vp4-h9-big sky.

i think it is a good idea also to add it to fm3 to have more effects and more quality.

if many people spend 799 euro for a big sky mx why not for a vp4 that it is a multieffect?
 
I figure I could get like $800 for selling my fm3, so wouldnt really save too much with the vp4 in terms of costs, then also not having access to the excellent amp sims, in the event I want them at times, seems like maybe giving up more selling a fm3 than I’d gain with the vp4 ?

If it was like $299, no brainer, would just add one for my synth rig, but at $700, fair price, don’t get me wrong, that is a lot of money for just effects that I basically already have, right ?
 
I agree with your logic. It makes no sense to sell the FM3 to purchase a VP4. The only case where I could see doing that is if I was using the FM3 100% of the time for effects only with an amp and it I was 100% sure that I would never need more than 4 effects at a time.
 
I would be tempted to get one to free up CPU and have four more switches, but my USB is busted so I'm more inclined to upgrade to a FM9.
 
I would guess that the FM3 users who are flirting with getting a VP4 aren't doing so in order to replace the FM3... they're considering it for the utility and pragmatics of using it in tandem with the FM3.
That's fine. For me, the FM3 does everything that I need.
 
I'm not doing an exhaustive search. Here's a few from users:
https://forum.fractalaudio.com/threads/new-fractal-product-coming.207160/page-23#post-2588557
https://forum.fractalaudio.com/thre...rm-factor-im-begging-you.184652/#post-2298534
https://forum.fractalaudio.com/threads/fractal-4cm-club.173106/page-3#post-2140998
https://forum.fractalaudio.com/threads/fractal-4cm-club.173106/page-3#post-2159674
https://forum.fractalaudio.com/threads/best-add-ons-for-your-fm9.182461/page-3#post-2246196

There are multiple threads about noise and hiss with the FM3 and 4CM. I have had mixed results myself when using the FM3 in 4CM.

Here's a post from @FractalAudio discussing the 4CM processing in the FM9.
https://forum.fractalaudio.com/thre...eler-fx-processor.176122/page-25#post-2138853

Here's a post from @Admin M@ confirming that there are some differences between the FM3 and FM9:
https://forum.fractalaudio.com/thre...-curious-about-something.198902/#post-2474704

It would be nice to get a statement from FAS regarding the circuitry of the FM3, FM9, AxeFX III, and VP4 with regards to their optimization for 4CM. A little clarity on that may help some users determine which unit is best for their use case.
I’m one of the users quoted here, and I can give a little more info on my experience. I have a bunch of Mesa heads, and I’ve used the FM3 with those and a few other brands as well (EVH, Synergy, Victory, and PRS). The FM3 is a stellar unit and it can be used competently in 4CM and will make most people happy. I just noticed the sound of the amps was not quite as good as when I ran my amps with other FX processors, notably the HX Effects in a similar 4CM configuration. I also did not like that I had to run an XLR to 1/4 cable out of output 1 to get 4CM to work correctly.

Moving from the FM3 to an FM9 for the same function all of my concerns dropped. The FM9 sounded better, and I could use standard quarter inch cables for the connections. The FM9 is immaculate as a 4CM option IMO. For the FM3, I can’t fully speak to the converters and I have no scientific tests to show results from, just my ears and experience using a lot of amps and effects processors over the years, I was not fully satisfied running the FM3 as a 4CM effects-only option.

I have a VP4 on order and can’t wait to try it. I am mainly looking to use it in tandem with my amp heads either in the loop or in 4CM mode while my FM9 remains connected to my PC as a utility device for writing and recording. With the recent FM9 updates, especially DynaCabs, it’s really become the most incredible all-in-one writing and recording platform, replacing several of my amps and pedals.
 
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