The acronym "FRFR" means "full range, flat response" and may apply to any class of audio devices: preamps, power amps, headphone amps, cabs, headphones, cables...). It indicates the fact that all the input signals of a same level (volume) in the 20-20k Hz range (the theoretical audio sensitivity range of a human being) are outputted at the same level regardless of their frequency.
The acronym doesn't correspond to any technical, industrial or scientific standard and has no meaning in itself (unlike, for example, the "HD-ready" standard for TV screens): it's nothing but an invention dedicated to the world of electric guitar players, to introduce them to the difference between a guitar amp\cab (which must not be FRFR in order to play good) and other kinds of amps\cabs: the growing success of digital modellers has created the need for the electric guitarists as well to look at flatter response, fuller range amps and cabs for better exploiting their modellers\profilers capabilities.
As a matter of fact, tho, no audio device in the real world is able to perform 20-20k Hz within 0 dB (that is, without differences in volume among different same-level input frequencies). Listen to 10 different studio monitors and you'll hear 10 (very) different sounds! But the best ones go as much as possible close to this ideal target.
Apart from guitar cabs, fx and amps, it would be advisable that any audio device had a very extended - and the flattest possible - amplitude response. These aspects are not enough for a device to sound great (others being the phase coherence, the transient response, the various distortions, the pattern of off-axis response...), but are both necessary.
So an audio device's quality is proportional (among other things) to the flatness and extension of its amplitude response. These qualities don't depend on the device class (that is, being it a PA monitor, a studio monitor, a Hi-Fi cab...), but can be measured in themselves.
As a final note, the frequency range of a given device has no meaning if the specs do not state at which amplitude (volume) a certain freq is outputted. For example, the Atomic CLR goes as down as 70 Hz @ -2.5 dB. This is an outstanding performance for the kind of device and its price class. Knowing that a cab goes down to 40 Hz doesn't mean anything if they don't tell you at which volume that frequency is returned. The CLR goes down to 40 Hz too (that is, it plays that back, at a lower volume), but Jay Mitchell is too serious to sell BS.
The accepted standard for amplitude response measurements in professional audio is +\- 3 dB, and the specs of the CLR being referred to a narrower range (+\- 2.5 dB) is nothing but a signal of extreme seriousness and professional commitment from Mr. Mitchell to anyone able to interpret it.
It might be worth mentioning that a device can have FRFR even tho it's not 20-20,000 +/- 0 dB: it's not perfectly linear in an absolute sense, but it may be linear with respect to human hearing sensitivity: differences in dB become less meaningful as far as you move towards the ends of the hearing range. So that, a difference of say 2 dB @ 20 Hz or 19,500 Hz is completely negligible.
In the words of Jay Mitchell, designer of the CLR:
QuoteDisplay MoreA speaker's response can be "flat" relative to the ability of human hearing to hear deviations from flat. That is all that matters.
1. "The flattest of speakers" deviate from the ideal by less than +-3dB.
2. The ability of human hearing to detect deviations within a +-3dB range only exists within a portion of the audible spectrum. Outside of that range, the ability to detect response deviations is substantially less. Awareness of the capabilities and limitations of human hearing is a key piece of the ability to make credible observations about loudspeaker performance criteria.
Most people can hear below
200Hz and above 10kHz. But they cannot detect deviations from flat
response nearly as well below 250 Hz or above approximately 4kHz as they
can within that band.
3. Transparency in a monitor (which includes flat response as defined above) is more critical (IOW, more easily audible) for use with a modeller than for general PA use.
IOW, the CLR can be considered an FRFR device 
HTH 
Viabcroce,
That is, by far, the best definition and argument for FRFR I've read on this forum. It should be memorized by all Modeler users! Thanks.
bd
Agree, should be wikied (the real one) under FRFR. 
Thanks guys! Glad you like it.
I've added something and edited my post a bit.
You've written "Atomic CLS"....is not a Mercedes.....
Agree, should be wikied (the real one) under FRFR.
My exact thought, and I know they guy who does the wiki, so I think I can get it done!
@ Davide: so funny! They're actually something more... a Ferrari, maybe?
(Thanks for the hint dude) 
@ Larry: thank you as well!
Studio monitors do not have enough wattage for live use and would not survive 1 month on the road. Different products
so why would i choose something like the CLR rd hd1221's over equivalent quality studio monitors? If i understand you correctly, if sonically they are more or less the same, its purely about the package they come in, wedges being considerable easier to transport and use live for instance?
Hey Alexander,
there are several kinds of studio monitors.
Those that stay close in front of you (within a meter more or less) are called close-field monitors, they usually exhibit a low wattage.
Depending on the application, for on-stage use you should consider mid-field (for monitoring purposes) or far-field monitors (for backline-FOH). These are suited for outputting a higher amount of decibels. I believe that such monitors (of equivalent quality and sonic transparency) would cost several times the CLRs.
Generally speaking, studio monitors are not built with the on-the-road life in mind, they are not as sturdy as PA cabs.
Why would you consider going on-stage with studio monitors? In order to use the same cabs at home and outside?
If this is the case, and your studio may benefit of mid-field or far-field monitors (you need space for this), you might consider going the other way round: a couple of CLRs could be the stone that kills the two birds for you. They are much more linear and transparent than many studio monitors, and play very well at low volumes.
I like how my Mackie MR8's sound for the KPA. And I could probably hang with a drummer with 2 of them.
But they have no grill over the cones, as most monitors don't. And when I move them, I'm afraid of puncturing the cone.
As said before, they are not "road ready" by any stretch.
So while you can get monitors that deliver on response and volume, they are built to hang in a studio and are more fragile in their construction and cone protection.
Wow, this is an excellent thread. Thanks viabcroce!
Well my main reason was im in the market to pick up some intermediate quality studio monitors (say Genelec 8030's for example). Not just for mixing purposes but to make playing with my Kemper even better. My intention was to only have these at home, as far a gigging is concerned, well id probably have to use my Boogie for now. But i keep reading various threads about the CLR or Mackie HD1221's and i notice alot of players i follow use the Mackie HD 1221's with their axe fx's. I figured it was for playing/touring purposes for the same reason you mentioned about taking studio monitors on the road. I just wanted some clarification that sonically they were more or less the same.
Basically, i'm trying to decide to how best split my budget between some studio monitors so i can mix my tracks but also something like the CLR or HD1221 so i can just plug and play with my kemper and also use it live in the studio. I already have some Sennheiser HD650 headphones which im currently mixing on right now, my crappy roland monitors are used mainly for my kemper and tracking, so i was thinking it might be best to get a cheaper monitor (say yamaha HS50) and but the majority on a CLR or likewise. Id rather save for longer spend the money wisely. Based of what you mentioned about the CLR's, a pair of those could solve both issues?
Well, while it's not opportune to take close-field monitors on stage, the possibility to use the CLRs in studio depends of the factors I've specified in the last part of my previous post. They take space, and you can't keep them 2 feet from your head. I'd say 6-7 feet is the minimum, and it would be better to not keep them against a wall or (specially) in the corners. So it all comes down to your studio's size and "sound".
Generally speaking, I'd advise you not to split your budget at all. If you need both cabs for studio and a solution on stage, I'd start with what I have: I'd buy a couple of great sounding studio monitors (saving on monitors\cabs\loudspeaker is IMO the biggest mistake a musician can do), use my amp live for now and save more to get the CLRs later. This would also allow you to buy just one CLR.
The main point implied by switching to the "FRFR" concept is that choosing a cab is not a matter of "sonic tastes" as it uses to be in the guitar cabs world. While one might prefer the Greenbacks over the Black Shadows for a guitar cab, when it comes to high fidelity in sound reproductions things become a lot tighter and objective. Unlike guitar cabs, with modellers the best amplification system is the most transparent, the most phase-coherent, the most headroom-gifted one.
From my personal perspective, it's advisable to spend at least 50% of the overall gear budget on a loudspeaker system (instruments excluded). For a 2k bucks digital device, spending 1k for an active cab is correct IMO.
I'm fully aware that many don't share this POW, and you'll always find people happy with their 199 $ couple of Behringer monitors... just to see their jaw drop when they're exposed to a professional sound reproduction system (and properly-translated patches).
As I wrote somewhere else, I don't buy the "I'm happy with my XXX, I can't see how my KPA\Axe\11R\YYY could sound any better!" attitude.
Ultimately tho, what matters most is that you're happy with your music and your sound, and receive positive feedbacks from people
Wow, this is an excellent thread. Thanks viabcroce!
Thank you BigB, glad you appreciate it
Thats great advice Viabroce. I actually didnt see this reply and just edited my previous response to make a little more sense of what i was thinking. And yes, im with you on this way of thing this way of thinking. I definitely agree on spending on monitors. Your only as good as your weakest link as they say. It definitely makes sense to spend at least 50% of your budget on the monitor side - as people most definitely do when buying a cab for their £2000 head. Actually i saw a pensado's place with Joe baresi and he was asked what he would buy if he only had $1000. I forget the specifics but he basically allocated 600 or 700 on the monitors.
Thanks for your great advice and your explanation of FRFR
Think ahead, and make wise choices!
