1 Topic by Mickster (edited by Mickster 2024-01-30 13:15:22)

  • Registered: 2024-01-30
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Topic: ADI-2 DAC FS with subwoofers

Hi everyone,

I've been trying to find the answer on this forum already but I'm still a little lost. I've ordered a ADI-2 DAC FS and want to make it the centre of my system.

My setup is like this:
RME ADI-2 DAC FS
Boxem Arthur 4215/E2 power amp
SVS SB-1000 Pro 2x
ATC SCM-19 speakers

I will be connecting the Boxem poweramp via XLR. The subwoofers I play in stereo, so left sub to left rca and right sub to right rca. This is how I'm used to it with the Topping D90SE I have now. With the RME the XLR runs 6db hotter than the RCA, which means I need to volume match.

So now my question is what is the preferred way to do this? Can I do this on the RME DAC and if so how or do I need to adjust the volume of the SVS subwoofers to match by ear?

I mostly went for the ADI-2 for the room correction (just want to try it out and see if I can work it out) and because I can use the Boxem on low gain with the voltage the ADI-2 can put out compared to other DAC's. Although that's another question on how to do that.

Thank you in advance for taking the time to read this.

2 Reply by KaiS (edited by KaiS 2024-01-30 22:01:48)

  • KaiS
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Re: ADI-2 DAC FS with subwoofers

The Boxem Arthur 4215/E2’s gain step medium-to-low is 8 dB.

So, if you are on medium gain, just switch to low gain and you‘re close where you‘ve been with the Topping.
Now bring down the subs a hair (2 dB) with their smartphone app and you’re done.

Or:
Leave the sub’s level, use a Room Analyzer (see below) and bring down the strongest room mode a little with ADI-2’s PEQ.
Then enjoy the stronger, but more punchy bass.


For senseful room correction a measurement tool is advisable:

If you have an iDevice, FFT from Andrew Smith / Studio Six Digital is a complete solution, Analyzer+calibrated microphone for 10 bucks:

https://apps.apple.com/de/app/fft/id298840058

KaiS's Website

  • Registered: 2024-01-30
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Re: ADI-2 DAC FS with subwoofers

KaiS wrote:

The Boxem Arthur 4215/E2’s gain step medium-to-low is 8 dB.

So, if you are on medium gain, just switch to low gain and you‘re close where you‘ve been with the Topping.
Now bring down the subs a hair (2 dB) with their smartphone app and you’re done.

Or:
Leave the sub’s level, use a Room Analyzer (see below) and bring down the strongest room mode a little with ADI-2’s PEQ.
Then enjoy the stronger, but more punchy bass.


For senseful room correction a measurement tool is advisable:

If you have an iDevice, FFT from Andrew Smith / Studio Six Digital is a complete solution, Analyzer+calibrated microphone for 10 bucks:

https://apps.apple.com/de/app/fft/id298840058

Thank you! Just got the Boxem as well so didn't realize the gain made such a difference. I do have it on medium right now. Was planning to use low gain with the RME on auto ref level. I think that is supposed to give the best sound quality? So then I will just put the volume of the SVS subs -2DB and I'm done?

Will also try the room correction tool when I'm more used to the sound and device!

4 Reply by KaiS (edited by KaiS 2024-01-31 08:32:12)

  • KaiS
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Re: ADI-2 DAC FS with subwoofers

New info found about the Topping here:
https://www.audiosciencereview.com/foru … ost-936510

This is the same like with ADI-2 DAC:
XLR is 6 dB hotter than RCA.
This means ADI-2 DAC is a 1:1 replacement for the Topping, level-wise.

So, switch Boxem to Low Gain, and set the subs 8 dB down from what they are now.
(Remember, 8 dB is the Boxem’s level step between med- and low-gain).



Or, if it’s all new anyway you might just set the subs’ levels by taste.

KaiS's Website

5 Reply by Mickster (edited by Mickster 2024-01-31 12:30:57)

  • Registered: 2024-01-30
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Re: ADI-2 DAC FS with subwoofers

KaiS wrote:

New info found about the Topping here:
https://www.audiosciencereview.com/foru … ost-936510

This is the same like with ADI-2 DAC:
XLR is 6 dB hotter than RCA.
This means ADI-2 DAC is a 1:1 replacement for the Topping, level-wise.

So, switch Boxem to Low Gain, and set the subs 8 dB down from what they are now.
(Remember, 8 dB is the Boxem’s level step between med- and low-gain).



Or, if it’s all new anyway you might just set the subs’ levels by taste.

That's interesting the Topping has the same level! I've only started using the Topping as a preamp for 3 days when I received the Boxem. The sub settings are still from when I used my Accuphase E407 integrated amplifier.

On the website of Boxem the gain settings are described like this: The first is to have the lowest noise, the second the smoothest volume setting as possible. High gain is optimized for sources outputting 2V, medium for 4V, low for gear able to provide 10 V.

I think the RME can do 7V tops? Would it then be best to have the Boxem at medium gain with the RME? And in that case maybe best to do settings for 4V? So instead of using auto ref level use settings within the RME to match the levels of XLR and RCA? If so what would then be the settings?

I saw you explain this for 2V in a different topic but have no clue how to calculate it for 4V (I think it's 3.74V to be fully accurate, going by this on the product page: Input sensitivity 8 Ohm 9.4 / 3.74 / 1.79 V).

Install the upcoming firmware, then you can switch Volume Display to dBu scaling, use +2 dBu for XLR, +8 dBu for RCA.
(Remark: XLR is always 6 dB hotter than RCA).
Meanwhile:
• Switch off Auto Reference Level.
• Use Reference Level +7 dBu and Volume -5 dB for the XLR out.
• Use Reference Level +13 dBu and Volume -5 dB for the RCA out.
Less conservative, if you don‘t need any headroom for DSP functions you could:
• Use Reference Level +1 dBu and Volume +1 dB for the XLR out.
• Use Reference Level +7 dBu and Volume +1 dB for the RCA out.
You end up with 1.95 V, the closest to 2 V that can be set.

Or should I just put on Auto Reference Level have the Boxem on either low or medium (and which one would be best, I think medium looking at the 10V needed for low gain) and then set the subwoofer settings by ear again. I don't mind setting the subwoofers again, just want the best SQ possible in the long run and the 6DB volume level difference threw me a little haha.

Sorry for all the questions but you know your stuff and I'm a little lost.

  • KaiS
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Re: ADI-2 DAC FS with subwoofers

You’re new to ADI-2 and just lately changed a lot in your system.
Possibly read a lot of confusing audiophile mumbo-jumbo about best sounding levels and such.

I’d like to clear this up and give you a good starting point.


1. Switch on Auto Ref Level in ADI-2.
It’s a very clever feature that automatically optimizes the reference level for each given situation.

2. Set the Boxem amp to low gain.
This allows ADI-2 to use the highest level, optimizes SNR and resolution.
ADI-2 can still drive Boxem to full power if you ever wish to make your neighbors call the police.

3. Forget all settings you had before and set the subs to the level that feels right FOR YOU.
That’s all that counts.


That’s all for the basics, done!


4a. For the next step, invest in a room measurement tool (see earlier postings) and optimize sub’s crossover frequency and phase.

4b: Look at the resulting frequency response and bring down the highest room-mode-related bass-peak with ADI-2’s PEQ.

KaiS's Website

  • Registered: 2024-01-30
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Re: ADI-2 DAC FS with subwoofers

KaiS wrote:

You’re new to ADI-2 and just lately changed a lot in your system.
Possibly read a lot of confusing audiophile mumbo-jumbo about best sounding levels and such.

I’d like to clear this up and give you a good starting point.


1. Switch on Auto Ref Level in ADI-2.
It’s a very clever feature that automatically optimizes the reference level for each given situation.

2. Set the Boxem amp to low gain.
This allows ADI-2 to use the highest level, optimizes SNR and resolution.
ADI-2 can still drive Boxem to full power if you ever wish to make your neighbors call the police.

3. Forget all settings you had before and set the subs to the level that feels right FOR YOU.
That’s all that counts.


That’s all for the basics, done!


4a. For the next step, invest in a room measurement tool (see earlier postings) and optimize sub’s crossover frequency and phase.

4b: Look at the resulting frequency response and bring down the highest room-mode-related bass-peak with ADI-2’s PEQ.

Thank you will do it like this! Boxem to low gain, auto ref level on subwoofers by ear like I always do as I don't like overpowering bass anyway and then enjoy. :-) Do you know if the low gain changes the power of the Boxem by any chance compared to medium (maybe more watts in medium?)? Think it tops out 220w in 8ohm and ATC do like a lot of power.

8 Reply by KaiS (edited by KaiS 2024-01-31 18:31:50)

  • KaiS
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Re: ADI-2 DAC FS with subwoofers

As mentioned, even with Boxem set to lo-gain, ADI-2 DAC can drive it to it’s full power.

ADI-2 max. XLR output: +22 dBu.
Boxem sensitivity for full power of 220W @ 8Ω: 21.7 dBu
This is a perfect match.

In reality you will hardly ever use more than 1W, so…
1 W would be at a ADI-2 DAC setting of -20.5 dBr (*1) with music running full scale - have a look what value you dial the volume to!


This “high power sounds better” is a improper generalization that made it’s way into the catalog of audiophile myths.

High power is better if it’s really used, e.g. in a club or PA system, taxing the amps to max.
Most real high power amps for this purpose (1-2 kW) sound like sh** when running at home hifi levels.



(*1):
The “r” in dBr denotes that Auto Ref Level is on, and the dBr value is referenced to ADI-2’s nominal full output of +19dBu.
ADI-2’s real full output is 3 dB higher, as there is some headroom built in for ISPs - Inter Sample Peaks.

KaiS's Website

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Re: ADI-2 DAC FS with subwoofers

But ATCs DO like a lot of power, like the OP said. Their drivers are heavily damped and very inefficient. My active 20s each have a biamp pack with 50w for each tweeter and 200w for each mid/woofer.

https://musicwall.app/hermetech

Babaluma's Website

10 Reply by KaiS (edited by KaiS 2024-01-31 18:54:09)

  • KaiS
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Re: ADI-2 DAC FS with subwoofers

Repeating a myth over and over again doesn’t make it true.

The ATC SCM19 have a sensitivity of 85 dB/W.
This is 3 dB more than typical Hifi.

Running them in the recording studio monitoring original dynamics live instruments I’d recommend the power you have.

For readily mixed and mastered music tracks at home this is of no concern, unlike one really listens loud, even louder than in the studio.

In this case (and only then!) I’d consider the subs underpowered.

KaiS's Website

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Re: ADI-2 DAC FS with subwoofers

KaiS wrote:

As mentioned, even with Boxem set to lo-gain, ADI-2 DAC can drive it to it’s full power.

ADI-2 max. XLR output: +22 dBu.
Boxem sensitivity for full power of 220W @ 8Ω: 21.7 dBu
This is a perfect match.

In reality you will hardly ever use more than 1W, so…
1 W would be at a ADI-2 DAC setting of -20.5 dBr (*1) with music running full scale - have a look what value you dial the volume to!


This “high power sounds better” is a improper generalization that made it’s way into the catalog of audiophile myths.

High power is better if it’s really used, e.g. in a club or PA system, taxing the amps to max.
Most real high power amps for this purpose (1-2 kW) sound like sh** when running at home hifi levels.



(*1):
The “r” in dBr denotes that Auto Ref Level is on, and the dBr value is referenced to ADI-2’s nominal full output of +19dBu.
ADI-2’s real full output is 3 dB higher, as there is some headroom built in for ISPs - Inter Sample Peaks.


Thank you, very helpful and insightful! Then I'll definitely use low gain for the best SQ. Getting the RME tomorrow if there's no delay with DHL. Very excited!