Audiolab DAC owners - Filters
- Thread starter Hcanning
- Start date
radamel
Music Fiend
I prefer Optimal Transient XD.
It measures worst in terms of FR but it's the one that sounds best to me. Apparently it does not suffer from pre-ringing.
Purité Audio
Trade: Purite Audio
Is that the one with significant intermodulation?
Keith
Keith
........... 
Yes. (If that's the second OT filter- the 3rd one doesn't suffer) It sounds rolled off to me and less clean, which pretty much is what's happening.
More often than not I am on the optimal spectrum, however it's obvious that someone's preference will depend on the balance of the rest of their system.
Yes. (If that's the second OT filter- the 3rd one doesn't suffer) It sounds rolled off to me and less clean, which pretty much is what's happening.
More often than not I am on the optimal spectrum, however it's obvious that someone's preference will depend on the balance of the rest of their system.
Digital filters represent one of the most readily audible variables in digital audio. There is no free lunch, the 'perfect' frequency response will have an imperfect impulse response. This is why Audiolab are naming their slow rolloff filters as "transient" filters at the expense of frequency response. It's good that people have options, and can choose which one they prefer.
Agreed, listen to what you like not what others recommend.
radamel
Music Fiend
Indeed. To me impulse response is way more critical than frequency response.
How do you know that what you like about the sound of those filters is due to their impulse response?
What about the impulse response of the filers used in the recording? Or any sample rate processing in between the master and the disc/file you buy?
In that respect the system needs to be taken as a whole, however I gather apodising filter may reduce the pre echoes potentially introduced by the above.
What about the impulse response of the filers used in the recording? Or any sample rate processing in between the master and the disc/file you buy?
In that respect the system needs to be taken as a whole, however I gather apodising filter may reduce the pre echoes potentially introduced by the above.
radamel
Music Fiend
Are you familiar with the concept of ceteris paribus?
So I was right, it was an unfounded assumption.
radamel
Music Fiend
Hahaha! You are very funny!
Purité Audio
Trade: Purite Audio
...........
Yes. (If that's the second OT filter- the 3rd one doesn't suffer) It sounds rolled off to me and less clean, which pretty much is what's happening.
More often than not I am on the optimal spectrum, however it's obvious that someone's preference will depend on the balance of the rest of their system.
Interesting isn't it, I wonder as a percentage how many listeners prefer that particular filter?
Keith.
adamdea
You are not a sound quality evaluation device
In this context I cannot see any meaningful application of ceteris paribus. BE's point stands- how does one know that what one is preferring is an impulse response difference? Certainly using an OT filter will affect the impulse response, the frequency response and add spuriae. How are the ceteris to be made paribus (and paribus to what?).
A minimum phase filter might more reasonably be compared with a linear phase filter of similar frequency response, but that's a whole different ball game, and may still depend on the (unknown) impulse response of the A/D filter.
adamdea
You are not a sound quality evaluation device
if it were possible, I would love to see the preferences of people who had not been told what the "right answer" was. Which would exclude anyone who has ever been on the M-dac thread.
radamel
Music Fiend
When everything else is constant (ceteris paribus) that is the recording, amp, speakers, cables, listening position, etc and ONLY the Audiolab filters are considered as a variable I prefer the OT XD.
According to JohnW, IIRC, this filter is better in terms of Impulse Response namely because it has no pre-ringing and performs not as well in terms of Frequency Response.
I'd say it does not take a great effort to conclude that to me Impulse Response is more important than Frequency Response. QED.
Sorry but I can't explain it better than this.
radamel
Music Fiend
Which one do you prefer?
adamdea
You are not a sound quality evaluation device
Yes you consistently prefer the OT filter; but as BE pointed out that does not mean your preference is based on impulse response: you may be responding to the frequency response change and/or the distortion (leaving aside the undoubted persuasive force of John's recommendation).I'm afraid that the reference to ceteris paribus does not take it any further.When everything else is constant (ceteris paribus) that is the recording, amp, speakers, cables, listening position, etc and ONLY the Audiolab filters are considered as a variable I prefer the OT XD.
According to JohnW, IIRC, this filter is better in terms of Impulse Response namely because it has no pre-ringing and performs not as well in terms of Frequency Response.
I'd say it does not take a great effort to conclude that to me Impulse Response is more important than Frequency Response. QED.
Sorry but I can't explain it better than this.
Aside from that it's a shame you're not interested in understanding the point BE is making: you can't meaningfully target the impulse response of the dac's filter only. This is dealt with incidentally in all the MQA papers and in Craven's paper on apodising filters. The OT filter will not optimise the impulse response if there is already considerable pre-ringing from the ADC process: it will faithfully reproduce that pre-ringing. If you want to remove it (assuming that pre-ringing really is a bad thing) then you need an apodising minimum phase filter
JemHayward
pfm Member
I used my wife, who has no knowledge or interest in the technicalities, and blind switching, and we settled on Optimal Transient XD - though the differences are pretty subtle to my ears in my system. I did swap over to Optimal Spectrum, and after a few days felt it was sounding pretty good, only to discover that it was back to OT XD again, as my wife has switched it back as it "sounded off". After that we gave up worrying about them and just listened to more music.