What are the advantages of having a second S1 Pro?

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Hello rodadamowicz@gmail.com ,


"What are the advantages of having a second S1 Pro?"  The three most important to me would be:  Wider coverage, stereo sound, and backup.


Having two S1 Pro's (or L1's, or F1's) let you cover wider side-to-side areas.  Every speaker has its usable range for effective listening.  Using two S1 Pro's sitting right next to each other won't do much for wide coverage or loudness, but spread them twenty or so feet apart, and you will gain a wider sound footprint.  You could even cover a remote area, maybe around the corner of a building.


I love listening to music in stereo.  Although the S1 Pro's 1/8" channel 3 input is a stereo jack, the S1 Pro itself is mono (it just combines the left and right signals into one mono output.)  With two S1 Pro's you can send the left stereo channel to one side and the right stereo channel to the other.  This can be accomplished with a mixer (via cables left and right), or by using the Bose Connect app to transmit a Bluetooth in stereo "party mode", i.e, left to one S1 Pro and right to the other.  Some music really excels in using stereo effects (a great example is "Never Been Any Reason" from Head East), while some just uses it to replicate the placement of instruments, or to separate instruments playing in similar frequencies so the listener can identify them easier.


Whether you are a pro musician or backyard DJ, if your unit fails, you cannot perform.  Having a second unit means the fun (and the job) keeps going, maybe just not covering as big an area.  This is not to say that we should expect the S1 Pro (or any manufacturer's gear) to fail, but unless you have some sort of backup plan and/or equipment (it doesn't necessarily have to be a second S1 Pro) things can come to a grinding halt.


I'm certain there are more reasons, and hopefully others will offer their comments.  As I said, those are the three most important reasons for me.


Does that help?

Hi Fish-54,


Thank you very much for your comprehensive response.


I did own a Bose L1 Mk2 until very recently (and also the S1 Pro) but have now parted with the L1 Mk2 as it was not being used very often and I couldn't really justify keeping it. Probably a big mistake.


Anyway, one or two of the venues that I have played (and possibly will again following the end of Covid  'Lockdown') may require a little more output/volume than a single S1 Pro can provide - hence my question re: "the advantages of having a second S1 Pro".


If I understand you correctly two S1 Pro's will not increase the overall volume/output into the venue/location but will provide a wider area coverage which is something that I believe may be quite beneficial. (e.g. L shaped rooms)


Also, as you have mentioned, another advantage is that two S1 Pro's allows for the opportunity to output in stereo - left channel to S1 Pro (a) and right channel to S1 Pro (b) - that's something that wasn't possible with the L1 Mk2.  I still have a T1 ToneMatch which will be perfect for such a stereo application. I suppose I could also 'daisy-chain' the units if a Mono output was required. 


Thank you once again for your really helpful advice. Will probably purchase another S1 Pro given the advantages you have mentioned - even as a backup. (peace of mind).


Kind regards,




Hello again, rodadamowicz@gmail.com ,


Thanks for coming back with your observations.  Daisy chaining in mono will definitely work.


However, using a T1 will not provide stereo without some special setup -- it is designed as a mono mixer.  It can be accomplished by routing one side to Master out and the other to Aux.  There are some instructions and notes in this link:  T1 Tonematch Audio Engine / Stereo Output to two L1's.  The same techniques apply for S1 Pro's (or F812's for that matter.)


Have fun!

Hi Fish-54,

Thanks once again for your very helpful comments and suggestions. Much appreciated. Will take them on board when I have purchased my second S1 Pro.

I'm sure I will 'have fun'.

Kind regards,


Hi Fish-54,

Can I pick your brains for additional advise re: S1 pro volume/output settings. By the way I have purchased a second S1 Pro since we last corresponded.


Two general/hypothetical questions.


1.  If I use all 3 channels on S1 pro number 1 - say Backing tracks from iPod/Mp3 player into Aux input - Vocal into Channel 1 and Guitar into Channel 2 with all the 3 channel volumes set at just below clipping/red, will the total combined output damage the unit in any way? Will the unit be overloaded and distort?


2. If I daisy-chain to the second S1 Pro using the volume/output settings as above into say channel 1 of S1 pro number 2, will the combined output/volume from S1 pro number 1 cause any overload/damage/distortion to the slave S1 Pro.


I don't ever expect to have settings as described above, I am just trying to understand the how basic  individual and combined volume settings interact with the one another ie limitations / pre distortion levels / possible damage to units etc. 


I hope you understand the above. Look forward to your thoughts when you have time.



Hello again rodadamowicz@gmail.com ,


Congrats on the second S1 Pro!


  1. The S1 Pro won't be damaged, as it has internal limiters.  I know that really heavy bass lines can make the woofer move a lot.  Some folks have commented that they think it sounds like it's "passing gas" 😄 when it does, but the built-in protections will keep it from damage.  But hey, it's only a 6" woofer!  It all depends on the source music, so if you're hearing distortion, just turn it down a tiny bit at a time.
  2. The Line Out to the second S1 Pro will be a nice hot signal, so just gain stage the second unit so you get green with occasional pops of red (same as you do for the first unit's three channels) and you'll be fine.  As with the first unit, if your ears tell you differently, just turn it down.

If you're a "set it and forget it" type of musician, or running strictly on battery, this will work just fine for you.  If you're constantly tweaking settings (as I do -- it's a curse!) you may prefer to use your T1 (of course, only if I have AC power) so it's at your fingertips.  Otherwise, you have to leave the mic, go back and fiddle with the back of your first unit, and hope you got the settings right.  Whatever works best for you!


Does that help?

Hi Fish-54,

Thanks once again for your reply and yet more really helpful advice.


Knowing that the S1's have built-in protections which should keep them from damage is very reassuring. I was just fearful of input overload and causing major problems.  


At the moment my setup is as follows:


1. Backing tracks from iPod into ToneMatch T1 channels 4/5 then Master Out into channel 1 of S1 Pro;


2. American Strat into Line6 Pod HD500 - L & R outputs into T1 channels 2 and 3 respectively - then Master Out also into channel 1 of S1 Pro; (volumes balanced/mixed using ToneMatch controls)


3. Vocals (Shure SM58) into TC Helicon Mic Mechanic then directly into channel 2 of S1 Pro. (didn't want to overload the S1 Pro channel 1 by sending everything to the one channel).


The main problem I have is that it is awkward trying to adjust and balance the independent volume levels re; channels 1 and 2 of the S1 Pro. (dictated by the venue)


Now that I know it is unlikely to cause damage to the S1's, I may experiment by feeding the vocals into the T1 (channel 1) meaning that I can then balance all channel volumes ( B/T's, Guitar and Vocals ) and feed all tracks from the Master Out of the T1 into channel 1 of S1 Pro number 1.  Any overall volume output changes will be via the Master Volume control of the T1. From there 'daisy-chain' to second S1 Pro.


Does any of the above make any sense at all or is there another, better way to set things up?


Any advice much appreciated. Thanks again.







Hello again Rod,


I'd run everything through the T1 to simplify balancing it all.  You won't overload your S1 Pro ... it all gets mixed together before it's fed to the S1's power amp anyway.  (Consider large shows where many instruments and vocalists are all combined on a large mixing board and sent to the speakers.)


Does that help?

Hi Fish-45,

Thank you once again for your advice and helpful suggestions.


Everything now seems to have fallen into place and I am feeling so much more confident about how to go about organising my 'setup'. You have certainly provided me with answers and solutions and I am extremely grateful that you have taken the time and trouble to reply to my 'novice' questions etc.


Very many thanks,