FM3 into tube amp or solid state power amp?

R

riffsordie

New Member
I just got a new FM3, but I haven't gotten to dive into it yet. I plan to still push air on stage with a real amp and 4x12 cabinet. I want to hear from experienced users about whether the Fractal gear sounds better when amplified by routing to the FX return of a tube amp VS into a clean solid state power amp. Which sounds better? Does anyone notice a difference that's worth mentioning?

If routing to the FX return of a tube amp, is it wise to send the signal without the Fractal amp block's "supply sag"? (I know not to use a cabinet block on the signal that's going to the real amp+cab).

Thanks for your help!
 
For my usage, I use a SS power amp and cab(s), as then I have total control over the SPL, and I'm not dependent on the real tube amp's "sweet spot" SPL, rather I get the "sweet spot" from the modeling.


YMMV?
 
I currently run my FM9 into a Mesa 2:Ninety tube power amp into a full stack. I want to love my Matrix SS power amp through the same cabs, but the Mesa just feels better. Recorded tone comparisons are like 99% between the two, but tubes hit the guitar cabs different IMO. Matrix does sound more clear and clean in my experience, if that makes sense.

In the end, I needed to try both to form my opinion. Forums are typically split 50/50
 
DearMrKev said:
I currently run my FM9 into a Mesa 2:Ninety tube power amp into a full stack. I want to love my Matrix SS power amp through the same cabs, but the Mesa just feels better. Recorded tone comparisons are like 99% between the two, but tubes hit the guitar cabs different IMO. Matrix does sound more clear and clean in my experience, if that makes sense.

In the end, I needed to try both to form my opinion. Forums are typically split 50/50
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I do agree, though you are then trapped by the tube amp's sweet spot SPL if you're using the tube amp as part of your distortion generation, but if you're not or have no SPL limitations, then the tube power amp is the way to go IMHO.

I use SS power amps for convenience sans SPL limitations, not for superior sonics or feel.
 
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A FM3 and a well built solid state amp being run how it was designed can pretty much nail anything you want if you get the right one made with quality components.
 
There are pros and cons to either type of power amp choice.

Tube amp pros:
1. Perfect match of power amp to impedance curve to the speaker cabinet
2. A lot of stored energy to accurately reproduce high energy transients
3. If you use the effects return of a guitar amp, you probably don't need to buy anything to get up and running

Tube amp cons:
1. Poor portability: heavy, large
2. Expensive upkeep (tube prices are insane these days)
3. Stereo requires either two amp heads ($$$) or a dedicated stereo amp such as those from Synergy, Fryette, and Mesa ($$$)
4. Not truly flat response, so they impart their own sound signature onto the tone from your Fractal device
5. You'll have to compromise when deciding how to adjust the impedance curve in the amp block of the FM3 to avoid the additive effects of the amp modeling and the natural impedance curve response of the tube power amp / speaker cab.

SS amp pros:
1. Truly flat response; what your FM3 puts out is cleanly and accurately amplified with a quality SS amplifier
2. light weight and easily portable options are available
3. More durable and less expensive to upkeep than tube amplifiers
4. Stereo is commonly a standard feature
5. No concerns about additive reactive loading effects since solid state amplifiers are impervious to the effects of reactive speaker loads
6. Many high quality options can be purchased inexpensively on the used market

SS amp cons:
1. SS amplifiers will require you to match the FM3 speaker impedance curve to the cabinet manually for more authentic response and feel
2. SS amps vary in quality. Light weight and inexpensive options often do not have much stored energy to accurately reproduce high energy transients and don't sound good at higher SPL
3. There isn't currently a high quality SS power amp on the market that is made with guitarists in mind, so many of the best sounding options are 2 rack space PA oriented amplifiers which are heavy and are best suited to being transported in a rack case.

It all comes down to which compromises suit your use case better.

When I play through a power amp into guitar cabinets I use a QSC RMX2450 that I purchased used locally for $175 and it sounds awesome. I used the DATS V3 to measure the speaker impedance curves of my actual cabinets to better match the modeled speaker impedance curve in the amp block to the response of my cabs. The only real compromise with this setup is that it would be a major pain to transport for live use because the RMX2450 is an absolute boat anchor.
 
Thank you all for your feedback! I've set up the 3 buttons on my FM3 for live use and mocked up the scenes that I will use on an upcoming tour. I'm excited to start the tonequest tomorrow. Cheers, everyone!
 
@OrganicZed :
Very interesting feedback ! Have you tested and have an opinion on the Seymour Duncan SS amp range?
I don't know much about the class D/H technology that equips most of our SS amps adapted to "FRFR" systems.
What differentiates a good class D/H amp from an average or even bad class D amp in terms of design.....
 
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Lolo-G said:
@OrganicZed :
Very interesting feedback ! Have you tested and have an opinion on the Seymour Duncan SS amp range?
I don't know much about the class D/H technology that equips most of our SS amps adapted to "FRFR" systems.
What differentiates a good class D/H amp from an average or even bad class D amp in terms of design.....
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I have the Seymour Duncan PowerStage 700. I think that it doesn't sound quite as good as the QSC I mentioned, but it weights something like 7 pounds and still puts out a healthy amount of power. If I were going to run a cab on stage that amp would be my choice because of the weight. The differences in sound are subtle and would be negligible for live use.

I am not an engineer, so my understanding of the various amplifier topologies is pretty shallow. I do not have sufficient knowledge of the design aspects to provide you with a useful opinion about what makes one amp good or bad. Here's a few quotes from Cliff about the subject.

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OrganicZed said:
I have the Seymour Duncan PowerStage 700. I think that it doesn't sound quite as good as the QSC I mentioned, but it weights something like 7 pounds and still puts out a healthy amount of power. If I were going to run a cab on stage that amp would be my choice because of the weight. The differences in sound are subtle and would be negligible for live use.

I am not an engineer, so my understanding of the various amplifier topologies is pretty shallow. I do not have sufficient knowledge of the design aspects to provide you with a useful opinion about what makes one amp good or bad. Here's a few quotes from Cliff about the subject.

View attachment 141212

View attachment 141213
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This type of info should be pinned or something. This way people can truly understand the how and most importantly the why.
 
@Sixstring It would be pretty helpful if Cliff did a Tech Notes thread on the topic of solid state power amps.

Here's a link to the thread that the previous quotes came from. Another notable quote from that thread when Cliff was asked to recommend a good SS power amp:

FractalAudio said:
There are plenty of good solid-state power amps but they aren't cheap. The QSC GX are very good. Crown are probably good but not sure about latency.
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My own personal experience from A/B'ing the SD PS 170 against a Fryette PS 2A and, then later on, a Fryette LXII.

- To my ears the SD PS 170 and the PS 2A did not sound that much different - especially in a mix. Definitely not worth the price different unless you want to use the other killer features that the PS-2A offers, which I did not.

- The SD PS 170 and the Fryette LXII had more of a difference with me preferring the LXII. In one situation I am routinely in, the other guitarist uses a dual rec racktoverb, and I felt the PS 170 did not keep up well, but the LXII shines.

- I definitely prefer the LXII for just playing by myself, to me it just makes me smile and inspires me. In a band/mix situation... I d k. When I need an amp, I'd still prefer the LXII, but I often use the PS 170, due to its weight and ease of transport. Plus the PS 170 is on my pedal board and ready to go.

Most of the time, I have no amp at all anymore when playing live. Straight to FOH and our IEM system.

IMHO, nothing beats trying options, as everyone has different metrics they use for deeming what sounds good. GC's return policy is great for this. Good luck!!!
 
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tobafett said:
My own personal experience from A/B'ing the SD PS 170 against a Fryette PS 2A and, then later on, a Fryette LXII.

- To my ears the SD PS 170 and the PS 2A did not sound that much different - especially in a mix. Definitely not work the price different unless you want to use the other killer features that the PS-2A offers, which I did not.

- The SD PS 170 and the Fryette LXII had more of a difference with me preferring the LXII. In one situation I am routinely in, the other guitarist uses a dual rec racktoverb, and I felt the PS 170 did not keep up well, but the LXII shines.

- I definitely prefer the LXII for just playing by myself, to me it just makes me smile and inspires me. In a band/mix situation... I d k. When I need an amp, I'd still prefer the LXII, but I often use the PS 170, due to its weight and ease of transport. Plus the PS 170 is on my pedal board and ready to go.

Most of the time, I have no amp at all anymore when playing live. Straight to FOH and our IEM system.

IMHO, nothing beats trying options, as everyone has different metrics they use for deeming what sounds good. GC's return policy is great for this. Good luck!!!
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Interesting. Have always wondered the difference in sound and feel of the LXII vs the PS2. Maybe something in the design causes this. Can you elaborate?
 
Matt007 said:
Interesting. Have always wondered the difference in sound and feel of the LXII vs the PS2. Maybe something in the design causes this. Can you elaborate?
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To my ear, the difference between the SD PS 170 and the PS-2A just wasn't that much, and I could be wrong but I don't think the PS-2A wasn't designed to be a neutral power amp. The PS-2A has a lot of cool features (FX loop, attenuation, direct out, etc) that I already had covered, so the cost just wasn't worth it to me. Don't get me wrong, its a cool product, I just have the majority of the bases covered with other tools.

The LXII is designed to be neutral and does it quite well in my opinion. As others have noted, the fan is pretty loud, but I have never noticed it during performance. My only WTF is the location of the trim pot controls for the presence and depth. If you want to change them - it would be a PITA - if the unit was racked. Since I only use it as neutral amplifier that does not cause me any issues. Just a weird design decision I guess.

So to sum it up, I believe that the PS-2A wasn't really designed to be used with a modeler specifically, and will color the sound. The LXII is designed to be used with a modeler (or not) - you can leave the power amp modeling on in the fractal products. Lastly, the LXII can be stereo, mono or bridged, so you can have 100 watts of power in a single rack space, whereas the PS-2A is 50 watts and is an odd size and shape for rack mounting.

Of course, it is all about individual taste, so I am sure some people run the PS-2A with the power amp modeling on, and love it.
 
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I only use my amps live for my personal feedback, so I don't have huge requirements on the subject. On the other hand, the subject interests me to have a global understanding of the audio chain.
Of what will contribute to having a quality sound or not..... In all the known brands (I won't give the name so as not to cause controversy) and used by "digital" guitarists I have never seen a manufacturer give an impulse response characteristic of its amplification system (do PA amplifier manufacturers do this?), it's a bit the same thing with the frequency response of FRFR systems, the response curve is not always available, while the linearity of the curve seems more important to me than the high and low cutoff values of the amplification......

If there are experts on the subject, their comments will be welcome to help understand the audio chain
 
Congrats on your new FM3! When amplifying Fractal gear like the FM3, the choice between a tube amp's FX return and a clean solid-state power amp depends on your preferences:

  • Tube Amp FX Return: Offers a warmer, more responsive tone with tube characteristics. It enhances dynamics and adds tube warmth.
  • Clean Solid-State Power Amp: Provides a neutral, transparent amplification without tube coloration, ideal for accurate reproduction of Fractal's tones.
Regarding "supply sag," many find bypassing this feature when using a tube amp's FX return can sound more natural, as tube amps already provide natural sag and dynamics.

Remember not to use a cabinet block on the signal going to your real amp and cabinet to avoid issues.

Ultimately, it's about personal preference and experimentation to find what suits your sound best.

Enjoy exploring your FM3!
 
OrganicZed said:
@Sixstring It would be pretty helpful if Cliff did a Tech Notes thread on the topic of solid state power amps.

Here's a link to the thread that the previous quotes came from. Another notable quote from that thread when Cliff was asked to recommend a good SS power amp:
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Thanks for linking that thread. I didn't want to necro that thread, but something I noticed is Cliff suggesting to turn output mode to "SS Power Amp + Cab" as well as turning off Speaker Drive and Thump. That sounds like you should have the Amp block set for either FOH or for an Amp+Cab, but not both.

I got a Matrix GT1000 for my Axe FX III rack. Haven't dialed in any tones yet, but the idea was to have an amp onboard that I could use to drive a backline cab at the gigs where they don't want to use my band's IEM rig and tell us to "just put your amp on the cab." I'd like to be able to still have a FOH send and a cab send. I planned on having one output go through a cab block and to FOH and another Output skip the cab block, but now it sounds like it may not be that simple.

The gist of my question is: does that mean I should have a 2nd Amp block for the cab output that mirrors my main amp block but with the tweaks Cliff mentioned in that thread? I know that doesn't apply to FM3 where THIS thread is in, but is that someone with an FM9 or FX3 should try to do?
 
I run two separate amp chains. One to feed a tube power amp/cabinet and another to feed FOH signal. I haven’t been able to dial in a single chain that feeds FOH and breaks off to output 3 (pre cabinet block) feeding matrix/cab that I’m happy with for both applications (yet).

This way, I’m 100% satisfied with both sound sources, regardless of what is needed. Ken Susi just released a video on YouTube and a post on the forum with a very similar setup, worth checking out!
 
DearMrKev said:
I run two separate amp chains. One to feed a tube power amp/cabinet and another to feed FOH signal. I haven’t been able to dial in a single chain that feeds FOH and breaks off to output 3 (pre cabinet block) feeding matrix/cab that I’m happy with for both applications (yet).

This way, I’m 100% satisfied with both sound sources, regardless of what is needed. Ken Susi just released a video on YouTube and a post on the forum with a very similar setup, worth checking out!
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Ken's video is what actually started my curiosity of using 2 different amp blocks for it. This thread is now getting me closer to doing it :)
 
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