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Choices of eq+cossover device that is as good as direct DAC to amp?

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Pdxwayne

Pdxwayne

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The problem is that it is not reliable at all.
You need to have someone switch between devices for you and do a proper blind test.
I know it's hard to believe, but sighted tests have fooled many people already.
Yeah, I know. In my case there is just one DAC that output both RCA and xlr at the same time.

Since I am comparing xlr out to two amps directly vs RCA out to minidsp to amps, this will require shut down and on of my amps constantly to switch cables, flip switch behind the amp to switch between balance vs unbalance, then adjust volume on my dac due to difference in voltages. Too much work for my family members and not good for my amps. The amps also need a little time to settle down once off and on. Thus not suitable for quick switch blind tests.

This is just not as simple as switching two DAC via RCA quick switch for blind tests, which I already done twice. Yes, I fully realize sighted listening can be very unreliable.

BTW, did you have a chance to try the steps I mentioned in post #16?
 
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Pdxwayne

Pdxwayne

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Did you do proper level matching for all tests?
BTW, when Amir measured Marantz 8805, the sinad is about 91db.

This is what Amir said:
THD+N is dominated by the third harmonic which means that it will peak above the noise floor of 16 bit CD content (96 dB dynamic range). So we lack transparency there let alone for high-resolution content.

So it seems we can just look at measurements and make judgements.

If you see post #77 picture, you will see analog in to minidsp is noisier than digital in.

I measured 1khz into analog of minidsp a while back and it looks like it has about 91db sinaq too, just like the Marantz.

Again, I have been using analog in of minidsp. Are there any measurements I can show you to make you agree that what I heard is likely correct?
 
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Easternlethal

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The problem I think is that you're looking for an external crossover solution that measures as well as one in a commercial speaker but afaik the passive crossover networks in commercial speakers are designed and built to match the specific properties of that speaker and external solutions just aren't at that level yet (even digital filters or electronic versions).

I have also been looking to integrate a mid range horn into an existing 3 way and am settling on an shd ->topping dac -> purifi.
 
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Pdxwayne

Pdxwayne

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This is one measurement from a while back using my loopback chain for minidsp hd 2x4. Note that the volume level is not exactly at 0db. Also, I am not sure how to properly interpret the chart. Someone helps to comment? Can one calculate the sinad of minidsp analog in based on the graph?

I see that 1khz tone is at ~-6db? 2khz harmonic ~-93db? Thus, sinad of minidsp analog in is at 87db?

Thanks!
matched_spectra_left_minidsp_hd.PNG



As a reference of my loopback chain quality, here is Gustard x16 measurement using same loopback chain:
matched_spectra_gustard.PNG


Edit:
I am not 100% sure, but I believe the minidsp got analog output from E30. Here is the E30 capture I did for different purpose, but I think still can provide a baseline to judge the chain vs minidsp added noise.
matched_spectra_left_e30_minus6.6db_peak.PNG
 
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Pdxwayne

Pdxwayne

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The problem I think is that you're looking for an external crossover solution that measures as well as one in a commercial speaker but afaik the passive crossover networks in commercial speakers are designed and built to match the specific properties of that speaker and external solutions just aren't at that level yet (even digital filters or electronic versions).

I have also been looking to integrate a mid range horn into an existing 3 way and am settling on an shd ->topping dac -> purifi.
How do you like your shd so far? Thx!
 

daftcombo

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This is one measurement from a while back using my loopback chain for minidsp hd 2x4. Note that the volume level is not exactly at 0db. Also, I am not sure how to properly interpret the chart. Someone helps to comment? Can one calculate the sinad of minidsp analog in based on the graph?

I see that 1khz tone is at ~-6db? 2khz harmonic ~-93db? Thus, sinad of minidsp analog in is at 87db?

Thanks!
View attachment 128064


As a reference of my loopback chain quality, here is Gustard x16 measurement using same loopback chain:
View attachment 128067

Edit:
I am not 100% sure, but I believe the minidsp got analog output from E30. Here is the E30 capture I did for different purpose, but I think still can provide a baseline to judge the chain vs minidsp added noise.
View attachment 128073
Those differences should be inaudible.
At which SPL fo you listen to?

Try two things:
- be sure that there is no EQ settings in the miniDSP that make the highest sounds reach more than 0dB; even more, put a pre-amp so that the highest sound reaches -1.1 dB (even if it seems overkill to avoid clipping)
- put a brickwall at 20 kHz in your playback software to avoid potentiel IMD of ultrasonics down the chain.
 
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Pdxwayne

Pdxwayne

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Those differences should be inaudible.
At which SPL fo you listen to?

Try two things:
- be sure that there is no EQ settings in the miniDSP that make the highest sounds reach more than 0dB; even more, put a pre-amp so that the highest sound reaches -1.1 dB (even if it seems overkill to avoid clipping)
- put a brickwall at 20 kHz in your playback software to avoid potentiel IMD of ultrasonics down the chain.

Thanks for the tips!

Typical prefer average listening level is 80 to 90 dbc, as measured from my seat, about 10 ft away from speakers. Peaks can be 95+dB, rarely would go over 100 dbc.

When I setup minidsp in the chain, I listened with minidsp app turned on and connected to minidsp. I have yet to see the output levels reach peak of the range, even when go loud. So the 0db peak thing so far not a concern.

Since I am using node2i as source, I don't think I can do brickwall.....Maybe I can try different filter on the dac?
 

daftcombo

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Typical prefer average listening level is 80 to 90 dbc, as measured from my seat, about 10 ft away from speakers. Peaks can be 95+dB, rarely would go over 100 dbc.
If you perceive a harshness even when you listen "only" at 85 dB SPL (which is very already loud), then it is theorically impossible that you hear harmonic distortion with any of the devices you provided graphs for (provided SNR is the same at higher frequencies than at 1kHz, which is not sure).

I am not used to the miniDSP app you talk about. Mine is only for setting the desired EQ and pre-amps, but not for playback listening.
 
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Pdxwayne

Pdxwayne

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If you perceive a harshness even when you listen "only" at 85 dB SPL (which is very already loud), then it is theorically impossible that you hear harmonic distortion with any of the devices you provided graphs for (provided SNR is the same at higher frequencies than at 1kHz, which is not sure).

I am not used to the miniDSP app you talk about. Mine is only for setting the desired EQ and pre-amps, but not for playback listening.
Yeah, there are still multiple freqs that are not measured for harmonics that could cause perceived harshness in around 8khz.

If you connect the app to the minidsp after you set it up and then play music, you can see the input and output levels live.
 
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Pdxwayne

Pdxwayne

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If you perceive a harshness even when you listen "only" at 85 dB SPL (which is very already loud), then it is theorically impossible that you hear harmonic distortion with any of the devices you provided graphs for (provided SNR is the same at higher frequencies than at 1kHz, which is not sure).

I am not used to the miniDSP app you talk about. Mine is only for setting the desired EQ and pre-amps, but not for playback listening.
BTW, since you commented on the measurements for minidsp, would you please comment on the measurements for other alternatives?

Please see https://www.audiosciencereview.com/...e-as-preamp-for-gustard-x16.21438/post-711214

I didn't use the Yamaha option due to ground loop issue I encountered when using external amps. But I think maybe I could solve it if I spend more time to adjust my chain.

Thanks!
 

Weeb Labs

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Have you considered a cheap ADAU1701 board with a USB-I2S interface? That would enable you to retain a digital signal chain between PC and DAC while simultaneously offering greater flexibility than a MiniDSP.
 
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Pdxwayne

Pdxwayne

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Have you considered a cheap ADAU1701 board with a USB-I2S interface? That would enable you to retain a digital signal chain between PC and DAC while simultaneously offering greater flexibility than a MiniDSP.
Thanks for the suggestion.

I have thought about digital DSP between source and my DAC.

However, there are two issues.

1. MQA. To enable mqa, node2i needs to be in fixed volume mode and directly connect to DAC. Even adding ADAU1701 in between, the DSP output would still need to be in max mode for my dac to decode mqa. Thus, volume control option is still from DAC side or from preamp ahead of DAC, which means crossover to the sub can't be in the ADAU1701.

2. BT. I like BT capability of my DAC. I sometimes connect my phone directly to DAC. In that case, ADAU1701 will not be helping.

Thanks again!
 
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