Help me choose a DAC for my Open Baffle system

[DavidVicente]

Hi, I think this is my first time posting, so please be nice!
I’ve been reading a bunch here, and learned a lot too during my modest hifi journey, so first big thanks to ASR and the community.
I’d like to respectfully pick members' brains on a new system choices for source and DAC as amps will be mostly chosen by the need of their onboard DSP. I’m leaning towards using two Crown XLS 1002, unless members suggest another 4 channel amp with DSP (Behringer NX4-6000 or NEXT A504 DSP 4-channel ?) as I don’t really want to add a miniDSP (and the learning curve). Amp budget would allow for the equivalent of 2 x Crown XLS 1002.

First I've had a simple open baffle design fabricated with twin 18" drivers from LiiAudio (the historical brand), without any design research, just trying to make my own following the usual OB designs. The drivers are on top a coaxial C1802, and bottom the W18 for lower frequencies.

I've been using the WIIM amp to feed the C1802 and the sub out feeding two Fosi ZA3 amps (in mono) for the W18, but not without issues (not sure what's wrong but some tracks show bad distortion for the bass).

I will relocate the WIIM Amp in my office, using an other pair of OB (being made now, with the F18) and a powered sub.

Regarding the twin drivers OB system, and suggestions are appreciated :
- Streamer : WIIM Mini (since I already have the WiiM Amp and don’t need Pro+) unless better solution but I think it’s hard to get any better here?
- DAC with balanced out (XLS or TRS) :
Topping E50, D30 Pro
SMSL RAW PRO DAC, M500, DO 100 Pro, DO 200Mk2, DL 200Mk2, DO400, SU-9 (the list seem to grow as I research)
Fiio K9, K7
Xduoo MU640
Schiit Modius
Loxjie D40 Pro
- Amps with DSP : a pair of Crown XLS 1002… or one XLS for bass and one tube amp for the mid/high?

What do you think of this combination, since the idea is to keep it affordable too?

Technically, the idea is to go from WIIM Mini to DAC via optical, then DAC to the Crown amps via balanced. The XLS back panel connections offer a TRS out to hook the second Crown amp. One amp will be feeding the W18 (using the onboard DSP to get the high pass filter) and the second Crown amp will the feeding the C1802 via his own low pass filter DSP.

Side question: does a DAC with tubes be a good idea to add in the chain? Or should I look into a regular tube amp with a sub out (like the Dayton Audio HTA100BT), to feed the W18 via one Crown XLS1002?

PS: I'm located in SEA and I'm also thinking of a power plug thing to isolate from potential surges (there's often power outage).
PS2: I might also need a WIFI box to boost signal if going for the WIIM mini…

 

[JeremyFife]

Sounds sensible: WiiM Mini => Optical => DAC => Balanced => DSP Amplifiers

Choose your DAC based on features, like having a remote if you want that, and get the cheapest one that does what you want (and that you don't mind the look of). Any Amp with DSP will digitise the input anyway - so all you want from a DAC is a clean signal to work from - your are basically looking for a pre-amp / volume control. Or find a DSP amp with digital inputs and skip the DAC.

Surge protection sounds sensible for you. Look at whole house protection if you can and don't fall into any 'audio' rabbit holes. This is electrical safety, not audio.
My WiiM Mini has pretty good wi-fi reception, no issues, so you might not need a booster. Easy to add in later.

I don't get the point of a tube amp in your setup - especially since you have made sure that you get a transparent signal. If you want added 'warmth' then you have DSP in the WiiM and in your Amps anyway. It's personal preference if you want this, but it's the one thing I wouldn't do.

 

[AnalogSteph]

I've been using the WIIM amp to feed the C1802 and the sub out feeding two Fosi ZA3 amps (in mono) for the W18, but not without issues (not sure what's wrong but some tracks show bad distortion for the bass).

Honestly, I would expect an OB setup to have some issues with (deep) bass. It's just one step above having your woofers floating in thin air after all, and I could not find an Xmax spec for the W-18 either (nor any specs that would allow deducing Xlin, like winding / pole plate height). Things are going to be severely excursion limited down low, with a 4th order acoustic dropoff in response. I would recommend having baffles as wide and tall as you can possibly accommodate and placing them near side walls, plus a high-order (maybe 4th) highpass in the signal path... try around 50 Hz or something. I would also want to have a measurement setup as I doubt the response will be particularly flat without some tweaks. The WiiM Amp should have quite sufficient PEQ capabilities for applying those.

 

[DavidVicente]

Or find a DSP amp with digital inputs and skip the DAC.

Thanks...
Oh, well yes, that's another can of worms...
No idea what DSP amp has also a good DAC integrated... A quick search show Behringer amps or the Minidsp SHD Power Amplifier that is quite expensive...

a high-order (maybe 4th) highpass in the signal path... try around 50 Hz or something.

Thanks, I'm pretty useless when it become too technical... What you mean here has to do with EQ or the DSP/filter?

 

[voodooless]

No idea what DSP amp has also a good DAC integrated

You do realize that every DSP amp has DACs, don’t you?

 

[DavidVicente]

You do realize that every DSP amp has DACs, don’t you?

Yes, that's why I added the adjective "good" before.

 

[voodooless]

Yes, that's why I added the adjective "good" before.

Yes, but that doesn’t make logical sense. You can’t skimp on your DSP amp just because you have one “good” DAC. This requirement therefore should be a generic one, not just for an all-digital connection. The DSP amps have an ADC to convert to digital. Generally, this is the weakest link in the chain. Then again, amp SINAD will probably drown whatever the DACs and ADCs produce, so I wouldn’t worry too much about it. Noise would be my biggest concern here.

 

[DavidVicente]

Yes, but that doesn’t make logical sense. You can’t skimp on your DSP amp just because you have one “good” DAC. This requirement therefore should be a generic one, not just for an all-digital connection. The DSP amps have an ADC to convert to digital. Generally, this is the weakest link in the chain. Then again, amp SINAD will probably drown whatever the DACs and ADCs produce, so I wouldn’t worry too much about it. Noise would be my biggest concern here.

Yes I hear you, the ADC step in the amp is redundant. Going from digital (streamer) to convert to analog (XLR to the amp) to get converted again in digital for the DSP in the amp seems counterintuitive. But I'm not sure if this really affect the final sonic results nor if it's worth searching for a full digital solution here, if it exist and at what price...
What power amp with DSP has a good DAC to connect via optical (or toslink/usb) at an affordable price, that is the question...

Edit: after checking with the MiniDSP (2x4 HD) I realised that it has optical in and could be connect like that with the WIIM Mini and feed a regular (rear RCA plugs) 4 channel amplifier. Any feedback on a similar set-up?

 

[DavidVicente]

Quick update, I got a Wiim Mini (and Umik-1) hooked to the Mini DSP 2x4 HD (still digging into the installation!) feeding four channels out of 5 of the AdCom GFA 5705. Will report back on finalizing the system if there's any interest.
Picture showing the two Fosi ZA3 that are replaced by a slightly less discrete box (north of 42kg for that beast)...