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Review and Measurements of REL Wireless Subwoofer Transmitter

pkane

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#41
My pleasure. I have a way to wire surround speakers but requires drilling holes so I may test the full bandwidth solutions there. Anyone wants to suggest one? I saw one from SVS I think.
Do you mean this one https://www.svsound.com/products/soundpath-wireless-audio-adapter?

Looks like it should work, but a bit disappointing THD+N spec of -60dB :) Frequency response looks good, and claims low-latency 16/48K transmission. Should be sufficient for surrounds.
 
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#42
If the transmission is digital can the experts here explain to me how wifi interference with a digital signal could cause distortion. Or is the measured distortion composed of the clicks and hiccups you would expect from interference with a digital signal?
And secondly, could other wifi based streaming devices also be susceptible to this type of interference?
That would open a whole new can of worms...
 

RayDunzl

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#43
My pleasure. I have a way to wire surround speakers but requires drilling holes so I may test the full bandwidth solutions there. Anyone wants to suggest one? I saw one from SVS I think
Here's a cheap pair, $58:

https://www.parts-express.com/dayto...ireless-audio-transmitter-receiver-s--300-594

A (similar/same?) pair came with one of my Cheezewoofers, I used them to send signal to Mother's room. I didn't notice a defect, but didn't measure them. There was a small delay.

The main idea was to permit the receiver in her room to play whatever might be playing loudly in the adjoining room, so she'd get the main sound instead of the probably annoying muffled bump-bump that would otherwise get in there.
 

NTK

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#44
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restorer-john

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#45

pkane

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#46
Ordered IFinity Wireless transmitter/receiver: https://www.amazon.com/gp/product/B00SJ49ZJQ/ for HT surrounds.

Cheap price, cheap looking, tiny two plastic boxes that are not much bigger than the tiny SMPS that come with them. Also comes with two sets of RCA-terminated wires.

Hooked them up to a DAC and to the back of JBL 306P Mk2 speakers... Pressed play, and it worked! Nothing to fuss with, transmitter and receiver automatically discovered each other. Music is playing, and sounds just fine, especially for HT surrounds. Needs RCA to XLR converter to connect to 306P, but I had those on hand.

Some quick measurements before installing this in the HT. THD+N is OK: 1KHz sine wave:

1570041596059.png


Frequency response, good to about 20kHz:

FR.png



If someone is interested in using this with a sub, here's the FR below 20Hz:
LF.png




Cross-talk seems good, around -90dB:
crosstalk.png


Jitter is also not awful for side channel speakers:
jitter.png


I'll try to set this up later and do some listening :)
 
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restorer-john

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#49
0.365 ms according to REW:
Did you see the amazon reviews where it clocked in around ~20mS? The A/D-Tx Rx-D/A will be more than 356uS...

The reason is the upper end of the FR plot will be otherwise measuring a lower frequency than indicated due to the delay.
 

pkane

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#50
Did you see the amazon reviews where it clocked in around ~20mS? The A/D-Tx Rx-D/A will be more than 356uS...

I have that one I pictured above, but I haven't measured delay.
The transmitter/receiver were on the same desk, about a couple of feet away. But that's what REW measured. In follow-up sweep, it came to around 1ms.
 

pkane

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#51
Ordered IFinity Wireless transmitter/receiver: https://www.amazon.com/gp/product/B00SJ49ZJQ/ for HT surrounds.

Cheap price, cheap looking, tiny two plastic boxes that are not much bigger than the tiny SMPS that come with them. Also comes with two sets of RCA-terminated wires.

Hooked them up to a DAC and to the back of JBL 306P Mk2 speakers... Pressed play, and it worked! Nothing to fuss with, transmitter and receiver automatically discovered each other. Music is playing, and sounds just fine, especially for HT surrounds. Needs RCA to XLR converter to connect to 306P, but I had those on hand.

Some quick measurements before installing this in the HT. THD+N is OK: 1KHz sine wave:

View attachment 34982

Frequency response, good to about 20kHz:

View attachment 34985


If someone is interested in using this with a sub, here's the FR below 20Hz:
View attachment 34995



Cross-talk seems good, around -90dB:
View attachment 34988

Jitter is also not awful for side channel speakers:
View attachment 34992

I'll try to set this up later and do some listening :)
All set up and working perfectly, took no time to hook this up. No issues whatsoever. No delay detectable by ear, but this is only there for HT 5.1 setup.
 
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