active subwoofer upgrade without having sub out

[anonyless]

my current setup:
laptop playing from Navidrome server --> SMSL PO100 (DDC) --> toslink to WiiM Pro input --> toslink output to SMSL SU1 --> RCA to 3e Audio A5 --> Q-Acoustics 5010s
very happy with the sound, specially with the WiiM room correction while streaming to it and from direct connection to the laptop.

Having said that, I'm thinking about adding an active subwoofer but I don't have sub out on the DAC or anywhere else -
my first thought is upgrading the SU1 to SMSL D200 , connect it the A5 with TRS cables instead of RCA, and use the D200's RCA outputs to the active sub, as from what I understand it outputs to RCA and TRS at the same time.
will this do the trick? for some reason I fear the D200 wouldn't sound as good as the SU1.
Also, the setup would force me to place the A5 above the D200, and the WiiM on top. will this affect the heat dissipation of the A5?

another reason I consider getting the D200 is its headphones amplifier, as I have a pair of HD600x near by that I hardly use, and currently I can only connect them directly to the laptop

 

[staticV3]

will this do the trick?

Yes.

Another option would be a Sub with Speaker level inputs, or a Sub with pass-through Satellite Line outputs.

Then you could keep your current setup.

 

[DVDdoug]

A lot of subwoofers have left & right inputs so all you need is a couple of Y-splitters. (It's OK to connect two inputs together this way but it's NOT OK to connect two outputs together.) Or if the subwoofer only has one input, you can use one Y-splitter with either the left or right since the bass is usually mono (the same in both channels).

Most subwoofers have a low-pass filter but a full crossover would have a complementary high-pass filter for the main speakers. The standard way of doing that is with the "bass management" on an AVR. (An AVR can also decode the "point one" LFE channel in moves for the subwoofer.) Or the miniDSP seems popular around here as a crossover or for room correction.

 

[anonyless]

A lot of subwoofers have left & right inputs so all you need is a couple of Y-splitters. (It's OK to connect two inputs together this way but it's NOT OK to connect two outputs together.) Or if the subwoofer only has one input, you can use one Y-splitter with either the left or right since the bass is usually mono (the same in both channels).

Most subwoofers have a low-pass filter but a full crossover would have a complementary high-pass filter for the main speakers. The standard way of doing that is with the "bass management" on an AVR. (An AVR can also decode the "point one" LFE channel in moves for the subwoofer.) Or the miniDSP seems popular around here as a crossover or for room correction.

I completely lost you here -
where do the Y-splitters come in with my current setup ?
the sub I was looking at has low pass filter, volume control, L&R RCA inputs - https://www.qacoustics.co.uk/products/q-acoustics-q-b12

 

[anonyless]

Yes.

Another option would be a Sub with Speaker level inputs, or a Sub with pass-through Satellite Line outputs.

Then you could keep your current setup.

thanks. could you give me an example of a sub with speaker level inputs? i assume that would mean i'd need to split the A5 speakers output

 

[staticV3]

where do the Y-splitters come in with my current setup ?

could you give me an example of a sub with speaker level inputs?

REL subwoofers often come with speaker level inputs.

i assume that would mean i'd need to split the A5 speakers output

Such subwoofers usually either come with cables that simply clamp onto your Amp's output connectors, or they have Speaker level pass-through outputs so that you can do Amp->Sub->Satellites.

 

[anonyless]

View attachment 449460 View attachment 449457

oh now i get it. thanks for drawing this for me. are there any downsides of splitting the signal from the DAC like this?

 

[staticV3]

oh now i get it. thanks for drawing this for me. are there any downsides of splitting the signal from the DAC like this?

Yes. You cannot apply a high-pass filter to your Mains, so you're stuck with running them full-range and have to adjust the sub to them as best as possible.

This is fixed by either a DAC with dedicated Sub output (e.g. WiiM Amp/Amp Pro/Ultra), or a Sub with pass-through Line outputs and Satellite filter.

 

[waynel]

my current setup:
laptop playing from Navidrome server --> SMSL PO100 (DDC) --> toslink to WiiM Pro input --> toslink output to SMSL SU1 --> RCA to 3e Audio A5 --> Q-Acoustics 5010s
very happy with the sound, specially with the WiiM room correction while streaming to it and from direct connection to the laptop.

Having said that, I'm thinking about adding an active subwoofer but I don't have sub out on the DAC or anywhere else -
my first thought is upgrading the SU1 to SMSL D200 , connect it the A5 with TRS cables instead of RCA, and use the D200's RCA outputs to the active sub, as from what I understand it outputs to RCA and TRS at the same time.
will this do the trick? for some reason I fear the D200 wouldn't sound as good as the SU1.
Also, the setup would force me to place the A5 above the D200, and the WiiM on top. will this affect the heat dissipation of the A5?

another reason I consider getting the D200 is its headphones amplifier, as I have a pair of HD600x near by that I hardly use, and currently I can only connect them directly to the laptop

I think you are going down the wrong path here. Proper subwoofer integration with bass management (including a high pass filter for the mains) is critical. I suggest getting rid of the WiiM Pro, and SMSL SU1 and replacing all that with a WiiM Ultra.

 

[anonyless]

I think you are going down the wrong path here. Proper subwoofer integration with bass management (including a high pass filter for the mains) is critical. I suggest getting rid of the WiiM Pro, and SMSL SU1 and replacing all that with a WiiM Ultra.

i took your advise and bought WiiM Ultra, connected it to QB12 sub and directly to the A5 amp. very happy so far

 

[anonyless]

@waynel i just realized i have "electrical" hum noises coming from the speakers when the A5 is turned on -
started troubleshooting as an electrical issue, then i came to a conclusion the noise appear on the A5 RCA input when the Ultra is turned on . could it be the Ultra's power supply is noisy? couldn't figure out. so "reverted" back and connected SU1 on the Ultra's spdif (and RCA's to the SU1 as well) - noises gone. maybe the RCA output is noisy?
open to any ideas

 

[waynel]

@waynel i just realized i have "electrical" hum noises coming from the speakers when the A5 is turned on -
started troubleshooting as an electrical issue, then i came to a conclusion the noise appear on the A5 RCA input when the Ultra is turned on . could it be the Ultra's power supply is noisy? couldn't figure out. so "reverted" back and connected SU1 on the Ultra's spdif (and RCA's to the SU1 as well) - noises gone. maybe the RCA output is noisy?
open to any ideas

Sounds like a ground loop. Try plugging everything into the same power strip

 

[anonyless]

Sounds like a ground loop. Try plugging everything into the same power strip

thanks , i started noticing the noises when everything connected to the same power strip, which is (unfortunately) connected to another smaller power strip. could that be the issue?

 

[waynel]

thanks , i started noticing the noises when everything connected to the same power strip, which is (unfortunately) connected to another smaller power strip. could that be the issue?

Even the sub is plugged in to the same power strip? Try disconnecting the sub and see if him goes away. I still think this is likely a ground loop.

 

[suttondesign]

a real gremlin, this. I hope you can solve it. The only bulletproof way is to use balanced connections or perhpas one of those wireless sound signal transmitters. SVS sells one.

 

[anonyless]

Even the sub is plugged in to the same power strip? Try disconnecting the sub and see if him goes away. I still think this is likely a ground loop.

yes, the first thing I did is disconnecting the sub's power cord. I didn't mention I have the A5 sitting on top of the Ultra - does this make any difference?

in oder to use balanced, I'll have to buy a new DAC.. too much right now

 

[waynel]

yes, the first thing I did is disconnecting the sub's power cord. I didn't mention I have the A5 sitting on top of the Ultra - does this make any difference?

in oder to use balanced, I'll have to buy a new DAC.. too much right now

try completely disconnecting the sub including the RCA cable from the Wiim Ultra. I think that the WiiM ultra can pass the filtered signal to the digital output so what you are doing now should work fine. To find the ground loop you want to pay attention to all connections including HDMI and 12V trigger ( I had a ground loop once due to a 12V trigger connection which I solved by disconnecting the ground from the cable).

 

[anonyless]

try completely disconnecting the sub including the RCA cable from the Wiim Ultra. I think that the WiiM ultra can pass the filtered signal to the digital output so what you are doing now should work fine. To find the ground loop you want to pay attention to all connections including HDMI and 12V trigger ( I had a ground loop once due to a 12V trigger connection which I solved by disconnecting the ground from the cable).

found it - the second i disconnected the sub's RCA from the Ultra, this noise is gone. I tried 4 different RCA's , including the one that came with the WiiM - didn't change a thing.
back to using the SU1 on spdif out , with the sub connected - no noises.
this is the RCA i'm using right now (only one cable connected) https://www.amazon.com/Stinger-SBTY2F-Bullet-Adapter-Female/dp/B00Q50CABG (Stinger Bullet), it's maybe 1.5m long and seems to work perfectly for me length wise.
what's the next step to solving this?

 

[waynel]

found it - the second i disconnected the sub's RCA from the Ultra, this noise is gone. I tried 4 different RCA's , including the one that came with the WiiM - didn't change a thing.
back to using the SU1 on spdif out , with the sub connected - no noises.
this is the RCA i'm using right now (only one cable connected) https://www.amazon.com/Stinger-SBTY2F-Bullet-Adapter-Female/dp/B00Q50CABG (Stinger Bullet), it's maybe 1.5m long and seems to work perfectly for me length wise.
what's the next step to solving this?

Its not the cable, it's a ground loop. Try powering the sub from the same power strip as everything else.

 

[anonyless]

Its not the cable, it's a ground loop. Try powering the sub from the same power strip as everything else

everything powered from the same power strip.
i suspected the power strip at the beginning of the troubleshoot, as it's new -
so first thing i did is disconnect it and used a smaller 3 socket strip to connect only the Ultra, sub, A5 - didn't help