Amplifiers with room correction: worth the cost or just a useless tech?

[marX]

Hello guys!
So, I have finally managed to land a full-time job and can afford costlier amps now. I'm looking to buy the AE100 Bookshelf speakers to save space and a decent integrated amp (2.1 or 2.0 channels) to start my journey. But I have come across a lot of posts about Dirac Live and similar competing tech which applies the equaliser as per the room nodes to produce good-quality sound from most speakers.

Given the higher cost, do you guys think it is worth it?

Also, are there any DIY options available in the £1000 region?

 

[radix]

There's a thread on using a Raspberry PI plus and audio interface to do dynamic room correction (DRC). Depending on your audio interface, this could be pretty affordable, if you only need 2 or 4 channels.

RPi4 + CamillaDSP Tutorial

Intent of this thread is to provide a tutorial for setting up CamillaDSP on a RPi4. There is a lot of good information scattered through ASR, DIYAudio and the CamillaDSP GitHub but there also appears to be a lot of apprehension. My goal is to give concrete examples of how to use CamillaDSP with...

www.audiosciencereview.com

 

[digitalfrost]

Room correction has been single biggest upgrade for my sound quality ever. If you factor in cost it becomes even more impressive since it really is not that expensive.

Personally, I would prefer standalone DRC solutions but whatever works for you.

 

[kemmler3D]

Also, are there any DIY options available in the £1000 region?

I do room correction with a mini PC (Windows 10), REW, and EQAPO. The mini-PC was about $120 on Amazon. The software is free... you still need a DAC (I use Topping DX5 Lite because it's got good performance, good output voltage, XLR out, and a remote for volume control) and maybe an ADC or other audio input (I just use a Soundblaster G3 for SPDIF optical in, it might be discontinued but apparently there are other options).

So as far as the room correction itself goes, you're only looking at <$250 for a DIY solution including the UMIK-1 (the go-to home audio measurement mic). There are loads of guides on how to get room correction done with the combination of UMIK-1, REW and EQAPO.

So in this situation you can use whatever amp you please and get the room correction at a low cost. Raspberry pi is also a good way to go, but I find Windows easier to mess with and it's not much/any more expensive.

If you have literally any old PC sitting around (laptop etc) and you don't have space constraints, that will work for EQ also. DSP of this type is actually not demanding on the CPU at all, so you literally just need any functioning computer built in the past 15 years or so. Macs also work but AFAIK there aren't as nice free options for the software on that platform.

 

[CapMan]

Totally agree that careful use of DSP has been a huge upgrade. I only address big room modes below 200Hz but the improvement in balance is massive.

I use REW and a simple UMIK1 to measure and apply the EQ in software (Roon in my case), but there are cheaper options.

 

[Mnyb]

Notice it’s a big deal but for correcting the room , but you can’t save bad speakers with for example directivity issues for several reasons .
I have some success with my old Meridian system on correcting the bass , it works .

So the budget solutions proposed in this tread are really good you can also just try , use the free software and your laptop and test what can be done, the laptop DAC may be subpar but you can test EQ solutions , to see if you want to go further.

Subwoofer(s) are also a great idea .

 

[marX]

There's a thread on using a Raspberry PI plus and audio interface to do dynamic room correction (DRC). Depending on your audio interface, this could be pretty affordable, if you only need 2 or 4 channels.

RPi4 + CamillaDSP Tutorial

Intent of this thread is to provide a tutorial for setting up CamillaDSP on a RPi4. There is a lot of good information scattered through ASR, DIYAudio and the CamillaDSP GitHub but there also appears to be a lot of apprehension. My goal is to give concrete examples of how to use CamillaDSP with...

www.audiosciencereview.com

Thanks guys for the replies!

I happened to have a 'free' RPI 4 lying around but I play games on my PC and would be cool to have it applied globally. And yeah, I have no way of testing currently as I haven't decided which amp to get, hence the question. I do have a Topping NX4 DSD dac which is decent and an earfun portable Bluetooth speaker. So, should I get a cheaper stereo amp and a miniDSP Dirac unit?

BTW, I was looking at the Arcam SA20 but it seems like its software is fucked up. Then there is a whole lot of NAD stuff which uses Dirac live with Hypex amplifier modules.
Those were the ones I was referring to but I no longer follow the HiFi scene and don't know if there is any other option out there.

 

[GGroch]

The Bru5 is an interesting amp with Full Parametric EQ and DSP capabilities. Sadly, it will not help absorb your new excess income. I am using a windows laptop, REW, and a UMik-1 to make the measurements. Wondom, the Ali-Express vendor will send you ACPWorkbench software that programs the DSP chip through a USB-C cable.

I have HiVi Swans DIY 2.2 speakers which are similar in size and efficiency to your AE100s, and the TPA3255 amp has more than enough drive for my small room. I have only had the amp for a week and am learning both REW and ACPWorkbench. It is not difficult, and I measured/flashed a very useable RoomEQ curve this morning that convinces me it is very much worth the effort.

 

[RosalieTheDog]

Stereo integrated amplifiers with room correction integrated are quite rare and often expensive (NAD) if I'm not mistaken. The new Yamaha R-N800a shapes up to be an interesting value proposition in this respect. I've heard good things about YPAO, although I guess if offers nowhere near the same possibilities of other options.

 

[Keith_W]

The problem with hardware based DSP room correction solutions is limited computational power and lack of flexibility. If it has 2048 taps (quite typical for an inexpensive DSP), then it has 1024 taps per channel. At 44.1kHz, this means the resolution for correction is (44100/1024) = 43Hz. If you are correcting only below 200Hz, this means you only have five bins to correct this region. If you don't know, a tap is a delay/coefficient pair.

Compare this to software based room correction like Acourate or Audiolense. Both have the ability to have 64k taps (65536), with the option of 128k (131,072) taps per channel if you wanted to. This translates to a resolution of 0.67Hz and 0.34Hz respectively. The problem of course is the cost of the software (about $400 for Acourate, about $500-800 for Audiolense depending on the version), and you also have to pay for a computer, a mic, maybe some additional software, and a DAC. If you don't want to pay for the software, you could find yourself a friend who owns the software to make some filters for you, and then all you have to do is host the filters in a convolver, or use a player that has a built-in convolution engine (e.g. JRiver or Roon). In that case the cost to you is only computer and DAC. But then you probably already own a computer and DAC.

Don't get me wrong, some DSP room correction is better than no DSP room correction. It's a matter of what your budget is and how anal you are about squeezing every last bit of performance out. If you are interested in software based room correction, there are quite a few knowledgeable people on ASR including the authors of both pieces of software I mentioned (even though we rarely see them around).

 

[radix]

Thanks guys for the replies!

I happened to have a 'free' RPI 4 lying around but I play games on my PC and would be cool to have it applied globally. And yeah, I have no way of testing currently as I haven't decided which amp to get, hence the question. I do have a Topping NX4 DSD dac which is decent and an earfun portable Bluetooth speaker. So, should I get a cheaper stereo amp and a miniDSP Dirac unit?

BTW, I was looking at the Arcam SA20 but it seems like its software is fucked up. Then there is a whole lot of NAD stuff which uses Dirac live with Hypex amplifier modules.
Those were the ones I was referring to but I no longer follow the HiFi scene and don't know if there is any other option out there.

The CamillaDSP + RPI tutorial is if you want a "middle box" for the DSP. If you are able to play directly from a computer (or the rpi), you could use Volumio w/ DSP or one of the other solutions people have mentioned for software DSP.

The important piece is to get a decent measurement MIC and have software that can generate the proper filters. DIRAC and ARC Genesis and Audyssey are meant to be simpler for a "regular" person to use. But the sophisticated software solutions (like Acourate or AudioLense) can give better results.

If you want to roll your own filters, you could start looking at some of these resources: https://www.audiovero.de/en/documents-and-tutorials.php. In particular the book "Accurate Sound Reproduction using DSP" is pretty good for a beginner walkthrough. If you search this forum or DIYAudio, you'll find many other threads about it. For example,

Understanding the State of the Art of Digital Room Correction

A deep dive presentation on the fundamentals of "proper" Digital Room Correction (DRC). Includes hands-on DSP FIR Filter Designer demos using Acourate and Audiolense. Having participated in many audio forum discussions, having watched online videos on Digital Room Correction (or DRC), and...

www.audiosciencereview.com

 

[marX]

The problem with hardware based DSP room correction solutions is limited computational power and lack of flexibility. If it has 2048 taps (quite typical for an inexpensive DSP), then it has 1024 taps per channel. At 44.1kHz, this means the resolution for correction is (44100/1024) = 43Hz. If you are correcting only below 200Hz, this means you only have five bins to correct this region. If you don't know, a tap is a delay/coefficient pair.

Compare this to software based room correction like Acourate or Audiolense. Both have the ability to have 64k taps (65536), with the option of 128k (131,072) taps per channel if you wanted to. This translates to a resolution of 0.67Hz and 0.34Hz respectively. The problem of course is the cost of the software (about $400 for Acourate, about $500-800 for Audiolense depending on the version), and you also have to pay for a computer, a mic, maybe some additional software, and a DAC. If you don't want to pay for the software, you could find yourself a friend who owns the software to make some filters for you, and then all you have to do is host the filters in a convolver, or use a player that has a built-in convolution engine (e.g. JRiver or Roon). In that case the cost to you is only computer and DAC. But then you probably already own a computer and DAC.

Don't get me wrong, some DSP room correction is better than no DSP room correction. It's a matter of what your budget is and how anal you are about squeezing every last bit of performance out. If you are interested in software based room correction, there are quite a few knowledgeable people on ASR including the authors of both pieces of software I mentioned (even though we rarely see them around).

Now this is a very interesting point! Haven't thought about this!
But do you have any idea about the latencies involved if using the software method?

 

[marX]

The Bru5 is an interesting amp with Full Parametric EQ and DSP capabilities. Sadly, it will not help absorb your new excess income. I am using a windows laptop, REW, and a UMik-1 to make the measurements. Wondom, the Ali-Express vendor will send you ACPWorkbench software that programs the DSP chip through a USB-C cable.

I have HiVi Swans DIY 2.2 speakers which are similar in size and efficiency to your AE100s, and the TPA3255 amp has more than enough drive for my small room. I have only had the amp for a week and am learning both REW and ACPWorkbench. It is not difficult, and I measured/flashed a very useable RoomEQ curve this morning that convinces me it is very much worth the effort.

That's pretty cool! Would have been great if they had a 2.1 version!

BTW, I used to follow 3eaudio but someone pointed out a hardware design issue and the 3eaudio guy was pretty defensive about it IIRC.

 

[kemmler3D]

Now this is a very interesting point! Haven't thought about this!
But do you have any idea about the latencies involved if using the software method?

The latencies are equal to the number of taps in samples. There is always a trade off between delay and frequency resolution. 1024 samples at 44.1 is 23ms, 65536 is more than one second of delay. So, the disadvantage of FIR filtering is that it eventually becomes incompatible with video playback, if you want to use your system for that.

The threshold for bad lip-sync is usually considered to be around 120-200ms, so you wouldn't want to use more than (say) 8192 taps at the very most, for any gaming or video applications.

 

[marX]

Stereo integrated amplifiers with room correction integrated are quite rare and often expensive (NAD) if I'm not mistaken. The new Yamaha R-N800a shapes up to be an interesting value proposition in this respect. I've heard good things about YPAO, although I guess if offers nowhere near the same possibilities of other options.

Interesting that Yamaha is doing this for their stereo amps. I have an AS500 amp in my country with a pair of Magnat speakers. Good for rocking it loud (speakers are 91 db sensitive).

I guess I need to listen to the Yamaha. Might probably do that tomorrow as the East Midlands area of England has a pretty good collection of hi-fi stores.

 

[marX]

The CamillaDSP + RPI tutorial is if you want a "middle box" for the DSP. If you are able to play directly from a computer (or the rpi), you could use Volumio w/ DSP or one of the other solutions people have mentioned for software DSP.

The important piece is to get a decent measurement MIC and have software that can generate the proper filters. DIRAC and ARC Genesis and Audyssey are meant to be simpler for a "regular" person to use. But the sophisticated software solutions (like Acourate or AudioLense) can give better results.

If you want to roll your own filters, you could start looking at some of these resources: https://www.audiovero.de/en/documents-and-tutorials.php. In particular the book "Accurate Sound Reproduction using DSP" is pretty good for a beginner walkthrough. If you search this forum or DIYAudio, you'll find many other threads about it. For example,

Understanding the State of the Art of Digital Room Correction

A deep dive presentation on the fundamentals of "proper" Digital Room Correction (DRC). Includes hands-on DSP FIR Filter Designer demos using Acourate and Audiolense. Having participated in many audio forum discussions, having watched online videos on Digital Room Correction (or DRC), and...

www.audiosciencereview.com

Thanks mate for the heads-up.
I'll be checking out the resources you mentioned.
I guess I need to do more research.

 

[Rednaxela]

There’s also this.

Audyssey Room EQ Review

This is a review and detailed measurements of the Audyssey Room Equalization. Audyssey is standard technology in a number of Audio/Video Receivers such as the Denon AVR-X3600H I recently reviewed. The standard version in the AVR is mostly all or nothing so I downloaded the Marantz/Denon...

www.audiosciencereview.com

 

[Overseas]

Room correction is worth depending... guess what... on your room.
My YPAO makes the difference in one of my spaces, but not in another.
Then it is the bass management, not my case, I am happy with floorstanders.

 

[marX]

Room correction is worth depending... guess what... on your room.
My YPAO makes the difference in one of my spaces, but not in another.
Then it is the bass management, not my case, I am happy with floorstanders.

Another good point!
I mean the place where I can get a demo, a hifi shop would be having treated rooms and the room correction system might not be pushed to its limits. Anyway, I have never been to a physical shop for ages. I'll pop in today to see how it is now.

 

[Overseas]

Also, usage or how to do it is not for granted. Ypao, Lyngdorf... these go by the push of a button. Not so for the famous Dirac, check it first.