BobWire XLR1 XLR and RCA Switcher Review

[Bob101]

Here is one use case. Suppose you have a 2 channel system - preamp, power amp, 2 speakers. You want to add a HT to your room. You buy another 3 speakers (centre channel + 2 surrounds) and an AVR. How do you use your 2 channel system with your HT AVR?

Answer 1: hook your 3 new speakers to your AVR. Send the line level out from your HT AVR to your 2 ch preamp. Problem: every time you want to use your system for HT, the preamp needs to be powered up and the input changed to HT. The volume control of the preamp needs to be adjusted to a pre-set level.

Answer 2: Buy one of these devices. Insert the device between the preamp and the power amp. Send the line level output for the 2 front speakers from the HT into this device. Now when you want to use the HT, there is no need to power up the preamp and do all the adjustments. This device automatically senses the input and switches to it.

While both solutions work, one of them is a more seamless experience. It is also less confusing for your family.

I can think of more use cases. For example, you could use it to switch between TV and 2ch audio. Or if your subwoofer has only one input, you could automatically switch between 2ch input and HT input. I have to swap cables between my DAC and my interface every time I want to do a measurement. This device will make that automatic.

Thank you.

 

[Rottmannash]

This is a 2 channel automatic bypass. Plug your AVR L/R preouts into the left input and your 2ch music DAC/streamer into the right.
The device autosenses which device, the AVR or DAC/streamer is in use and sends only that content through.

For me, the better way was to buy BobWire RCA1 and SPK1 which together get me the same thing but 2.1 channel.

Thanks. That makes sense.

 

[Rottmannash]

I use RCA>XLR adapters from the AVR line outs to the preamp. Should I incur the "penalty" of SINAD using the RCA ins on this or use the adapters? I assume the RCA>XLR adapters-that way I won't have to rerun Dirac Live. The 2 ch will have XLR from the preamp so this will work for me.

 

[Mort]

I use RCA>XLR adapters from the AVR line outs to the preamp. Should I incur the "penalty" of SINAD using the RCA ins on this or use the adapters? I assume the RCA>XLR adapters-that way I won't have to rerun Dirac Live. The 2 ch will have XLR from the preamp so this will work for me.

If you already have the adapters, I wouldn't go RCA. The downgrade may be inaudible but you have the cables.

 

[AaronJ]

This is a 2 channel automatic bypass. Plug your AVR L/R preouts into the left input and your 2ch music DAC/streamer into the right.
The device autosenses which device, the AVR or DAC/streamer is in use and sends only that content through.

For me, the better way was to buy BobWire RCA1 and SPK1 which together get me the same thing but 2.1 channel.

In my experience using similar devices the auto-sensing can be very fickle. Much better to use the 12V trigger. If your AVR doesn't have one, set up an auto-sensing outlet to run a 12V power supply. The trigger is always going to be rock solid.

 

[Mort]

In my experience using similar devices the auto-sensing can be very fickle. Much better to use the 12V trigger. If your AVR doesn't have one, set up an auto-sensing outlet to run a 12V power supply. The trigger is always going to be rock solid.

I will indeed report back. You are right, this has been true in the past. I'm a hopeful consumer that the price point might mean some better reliability on the auto sense.

 

[syzygy]

I designed a sense circuit with just 3 transistors (BC-5xx), ~32 years ago. No loading of significance with 68-100k per leg (L/R). Used it for a decade switching on and off my bedroom system and shutting it down 10 minutes after the last song finished. Could be used for switching anything in the presence of signal, even composite video.

View attachment 398206

One of the last draw it, etch it, drill it, make it projects from my ferric chloride and broken drill bit era in my 20s. I only dug it out recently to make a new design for my 91yo father, so he doesn't have to worry about leaving his various systems on for weeks at a time in his "HiFi room".

View attachment 398208

That's a very practical approach and solution, and exactly the way I would have done it - if I weren't so broke (back then) and cheap-by-nature that I built mine from salvaged relay, socket, connectors, and case - on solderless breadboard and fly-wiring a few parts.

Yours is superior, restorer-john - I've no doubt!

I do want to point out that, while some of us might say we'd do this or that differently, or in other ways add to the discussion in terms that might seem to 'question' the value/cost proposition, Bob Wire's product is likely much more sensitive, adjustable, including delays, while meeting the CE EMC Directive - which becomes more difficult when the functions are more sensitive.

That, as well as the testing it implies, and usually requires, doesn't come free, and it certainly doesn't happen without solid engineering & planning for commercial production.

Kudos BobWire!



Edit: I want to be clear - I'm NOT suggesting restorer-john was in any way 'questioning' the value proposition of the reviewed product here - I just combined 2 comments

I wanted to respond to restorer-john's build, first of all, because it looked familiar

but then I thought it would be a good place to contrast the 'ad-hoc' approach from a thoroughly developed product.

 

[yewneek]

Hello ASR community, I am Bob from BobWire. Thank you to Amir for taking the time to test my XLR1! I was an engineer/director of product development at Parasound products for 20 years. I left to start my own business (BobWire) last year. The XLR1 is my newest product but I also do make an RCA only version (model RCA1), speaker level (model SPK1) and some audio sensing device to activate 12V triggers (model AAT1 & DAT1). Keeping signal integrity throughout the audio chain has been a top priority in all of my designs and I'm pleased to see that the XLR1 maintains this tradition! (check out my website bobwireaudio.com for more info).

HI Bob!

Fabulous, and please stay that way! Wishing you the very best with your sales and endeavours!

GB

 

[enricoclaudio]

In my experience using similar devices the auto-sensing can be very fickle. Much better to use the 12V trigger. If your AVR doesn't have one, set up an auto-sensing outlet to run a 12V power supply. The trigger is always going to be rock solid.

Knowing now about him working with Parasound for 20 years, then I can tell you that the Auto sensing WILL work. The Parasound P5 I had was set in Auto sensing for the HT Bypass and worked 100% of the time.

 

[BobWire]

And that was the better option over, say, using a pair of high-impedance balanced receiver circuits with a low-power dual opamp and an inverting mixer (the single or dual transistor variety would basically do) plus just one instance of the detection circuit? The circuitry doesn't need to be low noise or distortion just as long as it loads the input as little as possible, so I might tend towards 470k or 1Meg resistors even (compensation for input capacitance likely required in feedback). Opamp wise, you could probably pull if off with an LM358 if you absolutely insist but a 4558 would probably be better.

Hello AnalogSteph,

Thanks for your comments. I hear you about the simplicity of taking this method. During my experiments, I had noise floor issues when trying to combine multiple signals into a single audio detector. The combined noise floor was giving me false triggers unless I raised the threshold voltage which I didn't want to do. I wanted the XLR1 (and all of my products) to have a super sensitive (very low signal level) sound level activation. This is less than 1mV of audio signal. When multiple channels or legs of the balanced signal are active at the same time, the voltage level required to activate my switch drops below 0.5mV. This ensures even the lowest volume levels will active the switch. I have tested several other products, including the old Niles stuff and they require too much of a signal to activate, making listening at very low volume levels impossible(especially with high sensitivity speakers). Some lower cost automatic switchers out there need half a volt to activate, making them useless when you have any volume control before the switch (you would need almost a full line out from your source to get the switch to work). I also made the audio detection work from 50Hz to 10kHz ensuring that no matter what you are listening to, the switch will activate. Going with 4 independent detection circuits seemed like the best way for me to get the really high sensitivity I wanted. Of course there is always multiple ways to solve a problem but this is what I landed on.

-Bob

 

[BobWire]

HI Bob!

Fabulous, and please stay that way! Wishing you the very best with your sales and endeavours!

GB

Thank you Yewneek! Trying to make the dream happen!
-Bob

 

[Rottmannash]

Bought one.

 

[BobWire]

Bought one.

Thank you sir! Let me know how it works for you. Every sale helps me develop more unique new products and fund production.

 

[BobWire]

Knowing now about him working with Parasound for 20 years, then I can tell you that the Auto sensing WILL work. The Parasound P5 I had was set in Auto sensing for the HT Bypass and worked 100% of the time.

Yeah, home theater bypass on the P5 was my idea and work. Actually all of the P5 features were mine. lol

 

[milosz]

You could use this for blind A/B testing, too. Testing of cables, for example. Or of amplifiers, preamps, etc. Maybe even DACs.

 

[pseudoid]

This not unusual for me; I am confused again:
*Output 'male' XLRs as "input"?

My next question would then be, either :
*Which interface provides an output for it?
or
*Does the word "input" refer to the trigger functions... somehow?

I wish this quality BobWire XLR1 leads to a more flexible product, which will switch 1-of-3 Input-pairs to become a 2nd Output-pair... even if that pair will require m<>f adapters!

 

[amirm]

In reverse mode it acts like a splitter.

 

[pseudoid]

Thank you @amirm,

In reverse mode it acts like a splitter.

"And alternative setup would have a single audio source and the XLR1 will switch between two XLR outputs (1 IN & 2 OUT) but this is only possible in 12V trigger mode."

To me: That statement sounds more like an "A/B" (exclusive-or) switch rather than a splitter (with simultaneous outputs).

 

[kelesh]

Cool but $$. Can't help thinking if Behringer made this it would be under $100.

They're probably already working on it.

 

[Mort]

I bought the RCA1, the unbalanced version of this and the auto sensing works very well between ARC/AVR and my 2ch setup. If it remains this consistent, it'll be worth the money to me.