Ok so I’d have to check this outside of HQPlayer then, if plot bandwidth is limited to 20kHz ?
I run the measurement at 48kHz, so just checking correction filter (PCM353kHz) response in REW to see it doesnt drop off before 24kHz ?
You should check that the correction filter response doesn’t drop off until 176.4k, which is Nyquist frequency of 352.8k filter sampling rate.
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If it drops off before, this is what the “Expand HF” in Matrix Profile is for? I forget the exact name because I’m not home
Is there any harm in leaving that enabled always ?
It only works beyond Nyquist of the filter. If the filter response drops off before Nyquist it won’t help…
Not really… In some cases it may make the filter longer, so it may increase processing load. If your filter is 352.8k, it covers 176.4k frequency range (when correctly generated) which should be enough for music content…
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So I can now comment on Acourate vs Audiolense XO
Acourate has a really quirky workflow if you are used to Audiolense
But I’m now quite used to this quirky workflow and i can generate frequency correction filters very quickly
driver time alignment is a different beast and is much more automated in Audiolense. More time consuming with Acourate
One thing I really like with Acourate is the ability to do a verification measurement right there inside Acourate itself
With Audiolense you need a separate convolver plus REW. Not a bad thing at all but just more steps
If trying to iterate multiple times, all that extra time adds up
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So, based on your many runs of Audiolense and verification with REW, how accurate is the Audiolense prediction to the actual? I use and like Audiolense but have taken @Mitch_Barnett on his word that the two match up. Your take? Thanks. JCR
Yes Audiolense excellent. If you keep the mic in the identical same position and re-measure at same SPL with REW+correction , you will get the Audiolense simulated response.
If you move the mic, well anything can happen depending on speakers and room and their interactions
Best to start with speakers with great off axis response
I used REW’s RTA to verify the FIR filters produced by ALXO once. The results were excellent!
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RTA works great but you can’t use it to see step response.
I use REW’s normal measurement chirp - since I can feed PC output through HQPlayer , it goes :
REW → HQPlayer pipeline matrix + filtering etc → NAA → speaker output → Earthworks mic → REW
I use the acoustic timing reference feature of REW, so the delay going through HQPlayer is irrelevant.
I learned a very slick way from Uli to avoid having to leave Acourate to test a filter without having to use REW. In ‘File’, select ‘Save Multiway Filter WAV’. Then select ‘Cor1L48.dbl’. Then all you have to do is add the multiway wav file in the logsweep recorder as a filter file and simply repeat the measurement.
Steve
Yes I’ve used that for the iterative process of creating better filters. It’s fast.
But in the end I also like to measure completely outside of Acourate, using my normal playback chain (with HQPlayer etc).
It’s also a good way to check if there’s any bugs in the playback chain, including HQPlayer! (have not found one yet 
)
Yes, see Jason’s biamped JBL M2’s with 4 subs using Audiolense XO:
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I have contacted HQP support several times, but I am beginning to get the idea that your knowledge here extends further.
As far as I know HQP is the only software with ‘digital’ inputs. Now my situation is also somewhat unusual, but I hope HQP will provide a solution for me.
The third party software I want to use is only available on macOS and I don’t want that in my audio environment. Furthermore in the third party software I need to assign an output e.g. a USB dac or other audio device which is recognized in MacOS.
I could use Blackhole software to reroute the sound to HQP, with the ultimate goal of getting the sound on a dedicated streamer or Windows audiophile PC with Lpsu etc…
If I am correct, you do have to manually change the samplerate via this route. Is there a better method?
Can I send the sound from HQP through the server function to another device (over the Ethernet)?
What is the best way to inseet the sound of the third party software in HQP?
Yes you’d need to manually change the sample rate in Audio MIDI for Blackhole and then switch in HQPlayer’s input also.
If you have an RME ADI-2 you can pipe any TOSlink or digital coax source (even if it means coming out of your Mac) through HQPlayer, and the sample rates will switch automagically - I do this even with iPad as my source.
Absolutely, like Roon has Roon endpoints, HQPlayer has NAA
With a Mac you would need something like 2x Raspberry Pi4s. One to be the HQP input from RME and the other would be your endpoint, connected to your (USB?) DAC
It would better help if you say what this mysterious 3rd party program is on your Mac 
And Are you already using HQP ?
And what DAC are you using
Also this is the Audiolense thread - are you using that too ?
Apologies for being somewhat mysterious about the specific 3rd party software, but this is for the good of the company itself. This is because they offer a software solution that requires the Mac, in addition they offer a plug and play hardware solution whose price is 5x higher.
With the above reason I wanted to send you a pm, but your account is public hidden. Hence, I also approach you here in another topic. Is there a way I can send you a pm? Than Im happy to mention the 3rd party software name + this thread stays proper.
I haven’t purchased HQP yet because I want to map out my route first. I was first considering a high-quality ddc with masterclock in conjunction with the Mac. But I prefer to send the output sound of the 3rd party software via a method to a dedicated streamer or audiophile PC over the ethernet as endpoint which is connected to my dac.
(Btw I already have one Rpi which now functions as a Diretta endpoint).
I have an Audio Note Dac3.1x/II that is limited to Spdif coax and Aes/ebu. Would I go for HQP or a DDC reclocking unit it gives double benefits since my dac does not use any kind of filtering, upsampling or shaping.
I wonder if for convenience I can’t choose the Rpi as the output device on the Mac? (To date, I don’t have a Mac yet, otherwise I would have already tried this option).
But only when ADI-2 is connected to a Linux based device.
If you have RME HDSPe AIO, same applies for Window based devices. So I have one Windows server with HDSPe AIO, and iPad connected through USB → AES → HDSPe AIO. Automatic rate switching works.
BACCH?
HQPlayer has it’s own endpoint protocol, called NAA.
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Ha we both guessed the mystery third party software. The price was the clue for me .
I continued this in the "any source " thread since this has nothing to do with Audiolense
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