Solved Desktop DAC/AMP with build-in PEQ

I have to ask where the M-Audio line stacks up these days. I know its old but it was good.I bought one right after this and it works great to this day even on Arm.

M-Audio MobilePre Digital Recording Interface
 
I have a FiiO Olympus 2 and it works with FreeBSD out of the box.
Basically what has been stated before: If it shows up as a USB audio class endpoint you're good to go.

If you want something more fancy with EQ settings and what not you might be able to set the values using a different operating system and then still use the device as a USB audio interface under FreeBSD. That is if those settings are retained by the device itself.
That is also good to hear that another FiiO device works out of the box.
I searched again, and my device have a USB-B, USB-C input port, and even bluetooth support so, if one option does not work the other one should, I think.

Regarding EQ there is no need for the device to have that option (and it has no EQ hardware wise) as I already have parametric EQ applied to my headphones through MPDs config file.
 
it is unfortunate that Motu M2 does not work in bitperfect mode. However, it is also expected. Not all or maybe most of USB devices do not. I wonder, whether manufacturers do some weird things with their USB protocols or FreeBSD USB stack needs some quirks. I tend to think it is the first. linux kernel ding some hackery to support wide range of devices. And it had to be the other way around - there should be strict UAC2 implementation across all the devices. And why it is not? Maybe we do not know the details? Reading https://forum.headphones.com/t/mis-understanding-usb-audio/6719 to get more about this topic.
 
reading this article also explains why old cards, specially that are based on Envy24HT are truly bit-perfect. These are PCI or PCI-ex devices that do not have usb transfer bottlenecks and pci transfer rate is enough to send/receive data uncorrupted. I was lucky to had ESI Juli@ PCI card many years ago ( they also upgraded the card for PCI-ex support but i forgot it's name, maybe ESI Juli@ Xte? ). It was fantastic sound quality.
FreeBSD has support for this devices
So, i maybe going to build a mini-PC, get a second hand ( or maybe new if lucky ) ESI Juli@. Get output from it to headphone amplifier ( and only amplifier ) And that's it. Everything else are the smoke, clouds and lot of fraud produced by audiophiles.
 
I have now tried the Motu M2 audio interface, too.
Sadly it does absolutely not work in bitperfect mode, it does not matter what I did.
I have a MOTU M2 laying around that I haven't used in some time. But it has always been a good audio interface for my own uses provided the OS had proper drivers (I've used it on Windows 7 and Gentoo mostly).

For anyone trying to get it to work you should be aware that there were several patches in the Linux kernel a few years back to bring proper support for the device. Here is the main one I had bookmarked from my attempts to get it going with Gentoo around the 5.x kernel series: https://web.git.kernel.org/pub/scm/.../?id=73ac9f5e5b43a5dbadb61f27dae7a971f7ec0d22

It needs a 2~ second delay and a couple of non-standard control messages sent before and after the delay. Would not be very hard to port I think.

Also this one to fix crackling: https://web.git.kernel.org/pub/scm/...t&id=c249177944b650816069f6c49b769baaa94339dc

There is/was a bug in the firmware that requires the 2-5 second delay. They never fixed it in firmware as far as I know preferring to hard code a delay into the drivers. So if your sound sub-system attempts to interact with the device before it's "ready" it will crash. This is also why there is a 2-5 second delay on it any time you change sampling rates.

Perhaps those tweaks simply haven't made it into *BSDs yet. I'll play around with this later when I have time to take my machine workstation down after I finish a production I'm working on. It's a really good device. Probably the best in that price range for what you're getting (the built-in LCD monitor is basically unique to it in the 2-4 input devices). The DAC in it is fine and can drive 250ohm headphones with plenty of power to spare. I often suggest it to people that want an audio interface for Windows/Apple devices.

Its been awhile but the company that produces it has always been pretty quick to respond to emails. Perhaps you should try contacting them to see if they'd be willing to bring driver support on freeBSD up to what it is on Windows, MacOS and Linux. They don't bother supporting platforms that people aren't making noise about.
 
I have a Focusrite Scarlett 2i2 gen3. I never tested whether it works in bitperfect mode.
Bitperfect mode is for me of uppermost importance, because it delivers the sound as it is.
It is loud enough, and I hear everything.
The problem for me is, and it took some time to realize it, the absence of space.
With my onboard chipset, no way, I hear a 24bit/96kHz flac and the poppings, cracklings, and distortion just appears.
During my test with the SMSL DO400 I noticed that with HPA set on, some instruments played, but for a short period, the flute just did not play, but it should.
The device overheated, though so, I do not care.

Today I opened a thread on the ASR forums just to ask whether I should get the FiiO F9 ESS Pro or the FiiO F19 Pro, both high end devices with clean lows, clean mids, and clean highs with superb sound without any negative comments on 4 reviews I read.
The person recommended my a $99 DAC the Topping DX1 with the comment that it should drive my focal utopia 2022 just fine.
I ordered it, too.
Now the FiiO F9 Pro ESS and the SMSL Topping DX1 should arrive next week, and I am quite suprised which DAC/AMP sounds better with the focal utopia 2022 headphones.
I think both should work in bitperfect mode, but I will report once I have tested both DAC/AMPs.
 
With my onboard chipset, no way, I hear a 24bit/96kHz flac and the poppings, cracklings, and distortion just appears.
That is caused by electrical interference on an analogue audio signal. That is why you shouldn't have analogue audio signal inside a computer casing. If you connect an external USB DAC to your computer, your computer will send digital signals to it. The analogue audio signals will be created inside the DAC without such interference. Bitperfect mode doesn't matter for that.
 
I've got some nice results with this setup. Mini pc with on-board realtek ALC269 codec, which is nothing special. Douk U3 headphone amp from ali, I haven't changed the op-amp, it comes with NE5532 installed. The amp is powered from a regulated 12V power supply. Drop HD 6XX headphones. I get no digital noise breakthrough, no hum, only very slight audible hiss from the cheap amp if I turn the volume up to the max, but I never have it that loud for listening to music. No crosstalk or distortion that I am aware of, good sound stage with nice separation/resoution of different instruments. Takes up very little space. Most of the time I don't bother with bitperfect just because it's more convenient to have multiple simulaneous sound sorces on the PC working. I have tried bitperfect, I think the difference is small. I'm quite pleased with the little amp, I wasn't expecting much but it actually seems pretty good. I think choosing a decent quality regulated power supply for the amp instead of a 2 dollar wall wart helps. No messing around with USB audio when using the onboard DAC. Maybe I just got lucky with the audio hardware implementation on this particular mobo, although it's only a bog-standard N100 mini pc.

It doesn't sound as good as my audio innovations valve amp with tannoy monitors, but it's pretty good for a low-cost setup on the desk. Very compact.
sound-setup.jpeg
 
I have solved my core audio problem.
Today I just realized that I need parametric 10 band equalization with every audio output capable software I use (games, movies, music).
To achieve that I searched for DAC/AMPs which support at least 10 bands on the hardware level.
I found the FiiO K19, read about it very carefully, and ordered it.
It should be USB compliant, and work in bitperfect mode, too.

On Tuesday or Wednesday it should arrive.
Once arrived I will try it out, and see how it performs.
If it performs well enough, I will recommend it.
 
I tested out the FiiO K19 today until now, and I am quite impressed.
Its DAC chips (ES9039SPRO) are both working fine with OSS bitperfect mode enabled.

For setting up the parametric equalization I needed to switch to Windows, downloading the DSP executable, and setting up a custom PEQ profile there.
Saving the custom profile, switching back to FreeBSD, and loading that custom profile on FreeBSD worked.
After doing some tests, there is indeed now PEQ enabled in every audio output capable application.

However I still got audio pop-ups so, I did the following to fix them:
-> Set hw.snd.latency=2
-> Set hw.snd.vpc_0db=49
-> Change audio volume to 78% on the FiiO device.

After 5 hours of testing the device, I cannot confirm that it runs hot, like stated in some reviews.
However, I am using that device vertical like it is intended so, both head sinks do not get blocked.
Audio quality wise compared to all the other DAC/AMPs I had until now, I am considering it to be clearly an endgame for headphones.

Regarding the SMSL Topping A70 Pro, I asked in the ASR forums, and a member said that it is an AAC (Analog to Analog Converter).
 
Nice headphones... :)

Yes, they are nice, but only with the right DAC/AMPs, and right sound settings or else you will encounter pop-ups and clicks.
I must say this headphones are the most petite ones I have ever had.
I also saved for like 7 months just to get them 😅

I also searched for a DAC/AMP which lets me adjust PEQ without being dependend on software for EQ. So, I can avoid pipewire, pulseaudio, jack and what not while having only one sound driver, and the strengths a EQ can give.
For example getting near to the Harman target curve.
 
Frequency response 5Hz - 50kHz (50k !!!)

Headphones that can reproduce down to 5Hz... very impressive.

I did a frequency sweep hearing test recently... was a bit sad to find I can no longer hear much above 13 kHz :'‑(. I think I can remember being able to hear 18 kHz when I was about 17 or 18, playing with a calibrated audio oscillator. Or it might be a thingumbob of my memory. Reelin' in the years...
 
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Turns out they still make them... a bit out of my price range, sadly! A very nice piece of equipment.

Ok, the Focal Utopia cost 4.999€ (out of my price range), but 15,950.00€ are way to much.

Headphones that can reproduce down to 5Hz... very impressive.
I have very good hearing that is why I decided to give them a try.
If you would ask me whether I would buy them again, I would say no, and eventually recommend Audeze LCD-5 headphones as they have a more accurate sound stage according to this review, and they seem to cost less.
But the Focal Utopia 2022 rev. was not a choice I regret I made.
 
I used digital camcorders and this walkman for recording beach events. MAudio DIO-2448 for capture. It was Bit-Perfect to me.

Sony charged alot because it had no digital protection. It was a pro-line model.
 
I rememember visiting one studio that was using DAT for recording, they had a rack with a stack of Sony DAT recorders in it. It was very good stuff. I suppose tape is history. Revox is top notch though, it's good to see they have gone back into production with the B77, it's a work of art.

And for analog freaks, this is the amp you need to go with your B77... (just don't look at the price, you need to be working at a crypto exchange). And you need a nice pair of Lowther loudspeakers to go with it :)

 
Yes I had a friend who was an audio nutjob. He had the double rack mount decks for DAT and would make copies of my recordings of his band.
He did soundboard recording and I had audience recording. Site at Mid-field right in the middle. Tripod Speaker Stand as microphone stand and pan/tilt camcorder location.
RIP Elwood.
 
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