Bose T1 master output

Bose product name

BOSE T1 mixer / L1 Compact PA





Detailed description of the issue and steps to reproduce


Hi folks. 


I've been using my T1 mixer with L1 model 2 and L1 compact for many years and love them.


I've a new gig where they have Bose installed speakers in the dining hall of the hotel. Not a huge room, but it means that if I connect to the system via an RCA red/white connection I can play my sound for full room coverage. While using my compact L1 as front of house speaker and monitor.


My issue is though as my master output from the T1 desk has to be connected to the line in on the L1 compact, I can only use the aux out to connect to the RCA house system. When I do this there is no reverb on my vocals? Think I read this is an issue using aux before. I don't understand why as the aux has settings for post fader. Is there a solution?


If not my second query is. Can I split the signal from the master output using a two 1/4 inch splitter cable. I tried and it seems to add lot of buzz / noise to both the L1 compact and the house system.

As I'm wary of damaging either or both, is that something I should be able to do or not.

Splitting the master signal?


Any other advice or solution would be appreciated. I know when I use my L1 mark two the master output is free for a second audio feed as the main connection is the tone match port which doesn't exist on the L1 compact alas.


Additional gear used (e.g. instruments, mics, FX pedals, etc.)

Shure Super 55 mic

Backing Tracks via iPad 

No other instruments


Where did you experience the issue? (e.g. home, bar, performance hall, etc.)



Hello hoohaa1980,


As you have discovered, there is no reverb on aux out of the T1.  There were some technical considerations regarding why, but it's always been that way ...


As for connecting to the house system -- the T1 mixer is a mono, balanced pro-level mixer while the inputs to the house system appear to be for unbalanced consumer-level stereo.  (That's why a simple Y-adapter doesn't work -- the and - balanced signal from the mixer is incompatible with the stereo left & right expected by the house system.  That's where the buzz is coming from.)  There are a several of solutions to your dilemma, depending on the amount of control and complexity you want.


The simplest connection is to run a dual-RCA male to dual-RCA male cable from the outputs on the back of your L1 Compact, at the bottom, to the house inputs.  That provides the same signal that your Compact is receiving, already summed to mono, and including any reverb or effects you've set.  I don't know how close your Compact is from the input jacks, but I wouldn't run any longer than a 6-foot cable.  You might get by with a 12-foot cable but expect the possibility of more noise.  The issue with this connection is that any change to the master volume on the T1 or on the L1 Compact will also affect the signal sent to the house system.  You won't know how your signal will match theirs until you try it.


The other idea is to get a small, inexpensive mixer that has RCA outputs, such as the Behringer 502.  This gives you several alternatives to control the signal going to the house separately:

  • You could run a 1/4" TRS to 1/4" TRS lead from your T1 aux out to channel 1 on the mixer.  Then run a dual RCA cable from the mixer's "2-track" outputs to the house inputs.  You control the volume going to the house with the aux control.  As discussed, there is no reverb on the aux out.
  • You could run a 1/4" TRS to 1/4" TRS lead from the 1/4" jack on the back of your Compact to channel 1 on the mixer.  Then run a dual RCA cable from the mixer's "2-track" outputs to the house inputs.  As in the first scenario, you will send a copy of whatever your Compact receives.  Using the mixer between the Compact and the house gives you a separate, intermediate volume control.
  • You could You could run a 1/4" TRS to 1/4" TRS lead from your T1 Master out to channel 1 on the mixer.  Then run a 1/4" TRS to 1/4" TRS to your Compact from the mixer's left 1/4" Main out, and run a 1/4" TRS to dual RCA cable from the mixer's "phones" jack to the house inputs.  This way, you are sending the same master to signal from the T1 to both locations, because the mixer has separate volume controls for main and phones.

If you use the separate mixer concept, run its EQ controls flat, so that the effects from your T1 are not changed.  It's always an unknown when plugging into someone else's system, but one of those solutions should work.  I guess the investment you make is proportional to how often you will be playing there!


Does that help?

Thanks so much for this quick reply. It's really appreciated.


I think the firsts solution should work, as it's exactly what I want.

Keep the sound / effects getting from my desk that go straight into my L1 compact, and just 'pass them on' to the house system through RCA. It didn't even dawn on me that was an option, as didn't realise the RCA were outs on the back of L1.


In theory I should just set the level during a sound check on house system, when I'm at the level I want to be playing at. Any increase or decrease of my volume would affect them but as it's a dinner show any increase or decrease I would want them to hear anyway. So finger's crossed you've solved my issue on suggestion 1.


As to the other options, appreciate them and I'll keep exploring.


My one query just for future knowledge though is, can you split a master output in theory to other speakers. For example.


1/4" TRS that split into two 1/4" TRS leads, allowing me to plug into perhaps two other speakers for coverage down the line. Just curious if it should be possible splitting a master signal with that kind of split cable.

Thanks again for this help! Liam

Hello again hoohaa1980,


Yes, it's easy to forget the 1/4" and RCA outputs on the lower rear of the Compact are there!  I'll be interested to hear how it works for you.


Regarding signal splitters -- Y-cables can be problematic.  There are plenty of mic-level splitters available, but line-level splitters seem harder to come by.  Whirlwind makes a line balancer/splitter that properly handles a line-level balanced signal, like the one provided by the T1.  On the input side, you can feed either an XLR or 1/4" TRS balanced line-level signal, and the other side provides two line-level XLR outputs.  In "ISO mode", one output is a straight pass-through of your signal, the other is a transformer-isolated clean "copy" of your signal.  In "Split mode", both outgoing signals are transformer-isolated, but with a 6dB drop in both signals.  The box's design eliminates any hum or buzz caused by grounding disparity between two systems.


Using a purpose-built interface like this makes the hookup simple and reliable.  You may need to get some XLR-F to 1/4" TRS or XLR-F to XLR-M cables if you don't already have some.  However, this interface costs more than a small mixer as I described in my earlier reply.


Does that help?

Thanks again man. 

Just to update you. 

I picked up and RCA to RCA cable today and went from Bose L1 Compact out to the wall house system RCA input. 

No joy. It had very little sounds and massive buzz when pushed it on wall. Seeing as it also did same with 1/4 inch out to the wall I’m guessing it’s something to do with the power / signal from the L1 Compact causing interference when routed to wall. 

When I take my aux out from desk (bypassing the L1 compact) direct to wall there’s no issues. I can live that but would prefer my reverb to be heard. I’ve not played around with delay yet but will when the room is free next. 

I’m very interested in the Di box style solution you’ve proposed though. I know there could be many factors (including the house system - but it does sound perfect from my aux) but in theory would this interface be a likely solution to what im describing?


Nearly there!

Hello again hoohaa1980,


Thanks for coming back to tell what did and didn't work.  I guess it just goes to show that without details on the jacks and exactly how they're wired, and what they're connected to on the other side of that mysterious wall plate, it's hard to give good advice.  Sorry about that.


I agree that if it works OK with the aux out, then it should absolutely work with the Whirlwind LBS Line Balancer/Splitter.  The only possible issue I can envision regards the volume control for that wall jack.  A change in the T1 master out will affect both your Compact and the house feed, so you'll need to manage the balance between the two.  Hopefully the house can control their speakers independently.  By the way, Radial Engineering makes a similar box, the LX2.  It's more expensive, but includes a trim control on the input side.


Good luck!