The FRFR Bible Thread

[EBS_freak]

@Frank Blank suggested that a FRFR thread akin to the IEM one (found at https://www.basschat.co.uk/topic/389429-the-iem-bible-thread/) So I'm currently setting up a thread and empty posts to start authoring... so it's currently very much a work in progress so standby...!

 

 

WELCOME TO THE FRFR BIBLE! - a beginner's guide to FRFR.

 

After another recommendation, I decided that I would start a new thread that is born out of the multitude of FRFR posts across the site.

Those threads contains a whole wealth of information – however, over time it has naturally become quite fragmented. A lot of information may have been superseded and of course, recommendations change. This thread, I'll summarise everything and try and keep all the important stuff in the first few posts of the thread. I'll do a few posts on FRFR, speakers, hardware, etc.. and build it up from there and keep chopping and changing stuff in the main posts as it happens - SO PLEASE DON'T QUOTE THE MAIN POSTS AS THE INFORMATION MAY GET CHANGED AND REFINED OVER TIME - thanks 

What I’ll do, is try and keep the opening posts updated with all the relevant bits and try and tie in any bits of interest. This should make it easier for people looking to quickly digest information around FRFR than reading all the other thread and no doubt bailing out before getting what they need out of it. I'll try and keep it at a fairly high level to make things easy to consume for the complete starter... so let me know if things aren't clear and I can refine them. Happy for contributors! Just PM content that you may deem suitable and I'll update as appropriate (I'm not precious about who writes this stuff)

So, without further ado...

 

SECTIONS

 

1. FRFR (https://www.basschat.co.uk/topic/418551-the-frfr-bible-thread/?do=findComment&comment=4079162)

2. Preamps and Modellers (https://www.basschat.co.uk/topic/418551-the-frfr-bible-thread/?do=findComment&comment=4079163)

2. Backline replacement (or can we get smarter?) (https://www.basschat.co.uk/topic/418551-the-frfr-bible-thread/?do=findComment&comment=4079164)

 

 

Edited April 9, 2020 by EBS_freak

[EBS_freak]

1.       FRFR

OK, so you are here probably because you are interested in finding out more about FRFR or have decided to purchase something FRFR and are looking for additional information.

 

1.1   WHAT IS FRFR?

OK, so what does this acronym FRFR actually stand for? Well, that's simple - Full Range Flat Response.

And in layman's terms?

It's a system that is designed to reproduce audio from sub bass through to piercing highs - that's the Full Range bit...

There are no sound characteristics, or eq, introduced into the equation. In other words, it's as neutral and faithful in the reproduction of audio - that's the flat response bit. Unlike traditional guitar and bass power amps and cabs (that tend to have their own sound signature), they are designed to be characterless - a blank canvas if you will.

 

Edited April 9, 2020 by EBS_freak

[EBS_freak]

2.       Preamps and Modellers

 

Edited April 9, 2020 by EBS_freak

[EBS_freak]

3.       Backline replacement (or can we get smarter?)

Edited April 9, 2020 by EBS_freak

[EBS_freak]

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[EBS_freak]

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------------ HERE ENDETH THE MAIN CONTENT - FEEL FREE FOR DISCUSSIONS UNDERNEATH! ------------

Edited April 9, 2020 by EBS_freak

[Lfalex v1.1]

Whilst I accept that an FRFR system will be noticeably less coloured (or have deliberate "voicing") than a traditional bass amp/cab or combo, they still have a couple of issues. One is generic to all sound reproduction using loudspeakers, one is more specific to bass guitar/single instrument amplification;

Achieving a flat response in an anechoic chamber or other controlled environment is one thing. Achieving it on a hollow wooden stage when the system has been shoved over to one side or to the rear because there's no space at the front is another altogether. These systems don't generally lack headroom, so it'd be nice if there were some way of EQ-ing out some of the more severe artefacts and getting back towards the design goal of a "flat response" (but in a real-world scenario) I once experimented with an old Trace Elliot head/cab and used a mobile phone app to produce a corrective curve to EQ out the worst of the room effects. That took about 2 minutes, and the results were surprisingly good.

Having done our best to achieve an appropriately flat in-room response, do we then have to start "chopping out" the undesired frequencies >12kHz probably doesn't have much useful content in the context of bass guitar save for some harmonic content. Conversely, gently rolling off the LF below about 30-35Hz helps take the strain off of the drivers and amplifier/s, leaving more clean headroom for any big peaks.

Then, of course, there's the signal chain before the FRFR system, which in many cases may deliberately compress, distort and mess with the phase or frequency content of the original signal... But that's another story.

The point being- I understand the design goals and breadth of applications for such systems. They may also be more compact and portable than traditional bass-specific amplification solutions, but it seems that, on the one hand, we are applauding the designers' efforts and on the other doing a significant amount to undermine them by the way in which we use the product..

[EBS_freak]

2 hours ago, Lfalex v1.1 said:

Achieving a flat response in an anechoic chamber or other controlled environment is one thing. Achieving it on a hollow wooden stage when the system has been shoved over to one side or to the rear because there's no space at the front is another altogether. These systems don't generally lack headroom, so it'd be nice if there were some way of EQ-ing out some of the more severe artefacts and getting back towards the design goal of a "flat response" (but in a real-world scenario) I once experimented with an old Trace Elliot head/cab and used a mobile phone app to produce a corrective curve to EQ out the worst of the room effects. That took about 2 minutes, and the results were surprisingly good.

There is. It’s called tuning your setup to the room and is what a 31 band is used for.

What you describe however, is the same for FRFR and traditional setups... so it’s a moot point.

2 hours ago, Lfalex v1.1 said:

Having done our best to achieve an appropriately flat in-room response, do we then have to start "chopping out" the undesired frequencies >12kHz probably doesn't have much useful content in the context of bass guitar save for some harmonic content. Conversely, gently rolling off the LF below about 30-35Hz helps take the strain off of the drivers and amplifier/s, leaving more clean headroom for any big peaks.

Most digital amplifiers will HPF at circa 40hz out the box anyway. As for the higher content, well, if you are using something like a modeller, all that EQing will be done in the model. If you aren’t using a modeller, then yes, your reasoning with regard to high end detail is right - if that is what you are looking for.

2 hours ago, Lfalex v1.1 said:

Then, of course, there's the signal chain before the FRFR system, which in many cases may deliberately compress, distort and mess with the phase or frequency content of the original signal... But that's another story.

What preamp or modeller you choose is up to you. Not every modeller does this - and given the amount of time purists out there, if this truly was the case (it isn’t) then the sales figures of these systems would fall in line with that argument (they don’t)

2 hours ago, Lfalex v1.1 said:

The point being- I understand the design goals and breadth of applications for such systems. They may also be more compact and portable than traditional bass-specific amplification solutions, but it seems that, on the one hand, we are applauding the designers' efforts and on the other doing a significant amount to undermine them by the way in which we use the product..

We can’t hold the designers responsible for shortfalls if the end user is not using the systems in the manner for which they are intended.

Edited April 10, 2020 by EBS_freak

[Lfalex v1.1]

1 hour ago, EBS_freak said:

There is. It’s called tuning your setup to the room and is what a 31 band is used for.

What you describe however, is the same for FRFR and traditional setups... so it’s a moot point.

Most digital amplifiers will HPF at circa 40hz out the box anyway. As for the higher content, well, if you are using something like a modeller, all that EQing will be done in the model. If you aren’t using a modeller, then yes, your reasoning with regard to high end detail is right - if that is what you are looking for.

What preamp or modeller you choose is up to you. Not every modeller does this - and given the amount of time purists out there, if this truly was the case (it isn’t) then the sales figures of these systems would fall in line with that argument (they don’t)

 

 

We can’t hold the designers responsible for shortfalls if the end user is not using the systems in the manner for which they are intended.

Alas that I don't own a 31-band EQ! Nor would my bandmates relish the time it'd take to set  up... I'd prefer a system that plays a bit of pink noise and calibrates itself..

I don't really like modellers, and the compression, distortion and phase anomalies I mentioned was an oblique reference to FX messing everything up again.

I think my issue is that I've spent so long playing exclusively though good quality headphones fed from a small mixing desk that nearly everything sounds a bit skewed by comparison.

[EBS_freak]

9 minutes ago, Lfalex v1.1 said:

Alas that I don't own a 31-band EQ! Nor would my bandmates relish the time it'd take to set  up... I'd prefer a system that plays a bit of pink noise and calibrates itself..

But that is something that is not relevant to FRFR explicitly. There are systems that do that - but they aren’t exactly perfect, especially because an empty room doesn’t respond the same way to a room with people in. Pink noosing a room with people in is pretty antisocial.

19 minutes ago, Lfalex v1.1 said:

I don't really like modellers, and the compression, distortion and phase anomalies I mentioned was an oblique reference to FX messing everything up again.

That’s personal opinion. Plenty of people do like modellers. Plenty of people like mic pres into a FRFR cab. In a blind test, most people can’t tell the difference between a traditional or modelled setup. Those that proclaim that they can are usually kidding themselves.

23 minutes ago, Lfalex v1.1 said:

I think my issue is that I've spent so long playing exclusively though good quality headphones fed from a small mixing desk that nearly everything sounds a bit skewed by comparison.

Ok. I’m not sure what you are asking or trying to achieve in this thread then...? If you are used to a desk into headphones, assuming that your headphones are fairly flat (or reference) and not a set with some crazy baked in response, then a channel strip (eg no modeller) into a FRFR cab would make perfect sense.

[molan]

I thought the purpose of this thread was to try and avoid all the random fragmentation already available across the site?

Padding it out with criticisms and personal opinions about why NOT to use an FRFR based setup seems very counter-productive 🤦‍♂️

[Chienmortbb]

On 10/04/2020 at 04:55, Lfalex v1.1 said:

Whilst I accept that an FRFR system will be noticeably less coloured (or have deliberate "voicing") than a traditional bass amp/cab or combo, they still have a couple of issues. One is generic to all sound reproduction using loudspeakers, one is more specific to bass guitar/single instrument amplification;

Achieving a flat response in an anechoic chamber or other controlled environment is one thing. Achieving it on a hollow wooden stage when the system has been shoved over to one side or to the rear because there's no space at the front is another altogether. These systems don't generally lack headroom, so it'd be nice if there were some way of EQ-ing out some of the more severe artefacts and getting back towards the design goal of a "flat response" (but in a real-world scenario) I once experimented with an old Trace Elliot head/cab and used a mobile phone app to produce a corrective curve to EQ out the worst of the room effects. That took about 2 minutes, and the results were surprisingly good.

Having done our best to achieve an appropriately flat in-room response, do we then have to start "chopping out" the undesired frequencies >12kHz probably doesn't have much useful content in the context of bass guitar save for some harmonic content. Conversely, gently rolling off the LF below about 30-35Hz helps take the strain off of the drivers and amplifier/s, leaving more clean headroom for any big peaks.

Then, of course, there's the signal chain before the FRFR system, which in many cases may deliberately compress, distort and mess with the phase or frequency content of the original signal... But that's another story.

The point being- I understand the design goals and breadth of applications for such systems. They may also be more compact and portable than traditional bass-specific amplification solutions, but it seems that, on the one hand, we are applauding the designers' efforts and on the other doing a significant amount to undermine them by the way in which we use the product..

If you are going to put an HPF in thhe system, the best -3dB point depends on the cabinet response  and it need to be quite vicious (24dB/Octave) to protect the drivers and take out the low end waffle.

[BassmanPaul]

I use 4Ω Acme B2 cabinets. They are a 2x10 three way box. Aside from bass I have used them as PA mains and also as subwoofers in my larger PA. Everything that I throw at them is reproduced cleanly and without effort. Playing a Low B through them is a pants flapping revelation. I use a pair of these with my bass in a vertical 4x10 stack driven by a 2KW Class D power amp. I own four and when I use all of them it's delightful!!

Edited April 26, 2020 by BassmanPaul