Old Bose Acoustimass System - hardly any sound from subwoofer (1 Viewer)

[Mathew Crow]

Hello everyone,

I just bought a used Bose Acoustimass 5.1 surround system from someone that included 2 front, 1 center, 2 surround, and 2 subwoofer speakers. The regular speakers sound fine but I hardly hear anything coming from the subwoofer. The guy I bought it from said this system was close to 20 years old. I haven't seen a setup like this before; maybe because its so old. The speaker wires go from the receiver to the subwoofers then out of the subwoofers to the other speakers. One subwoofer has connections for the front and center speakers, and the other one has connections for the rear surround speakers. The subwoofers don't seem to have any connection facilities at all to the receiver or other power source and their seems to be no place to connect them except with the other speakers. I'm assuming that they're taking power from the receiver through the other speaker wires before sending it on out to the speakers afterwards? I hardly can hear any bass at all with movies or music, event after turning the bass enhance feature on in the receiver (Yamaha VX-377) and turning the levels up for the subwoofer as high as they'll go on the receiver. I don't really know anything about stereo systems, but am I doing something wrong or do these subwoofers just suck?
Thanks!

Matt

 

[Carl Johnson]

Most speakers are designed to play a full range of sound. The Bose system does not have a subwoofer. It separates the low range sounds into the bass module, and passes on the high range sounds into the small cube speakers.

You could always buy a powered subwoofer and add it to the system by connecting it to the receiver. That would significantly improve the quality of the sound that you get from the system.

 

[JohnRice]

You probably were taken. I've never heard of a Bose system that connects that way, with a bass module for the surrounds. It sounds like a cobbled together set from various mismatched systems. One of many problems with Bose systems is they usually cannot be mixed together.

 

[JohnRice]

The first thing you need to do is make certain your receiver speaker settings are configured for not having a subwoofer. Then make sure at least the L&R speakers are set to "Large", which will probably happen automatically when it knows there is no sub.

 

[David Norman]

I am a bit confused about what's connected to what. I've seen computer speakers connected sort of like this though Bose has a unique

way of doing everything. I am assuming that the receiver and speakers were meant to be part of each other and these aren't mixed systems.

Do you have any model numbers for the receiver and speaker or does the receiver allow test tones to be sent to independent speakers?


My first snarky response with no bass coming from those modules would be that the Bose system is functioning exactly like it's designed to though

I suspect that wouldn't be helpful.


I think John's though about speaker setup may be at least part of the answer.

 

[Mathew Crow]

The first thing you need to do is make certain your receiver speaker settings are configured for not having a subwoofer. Then make sure at least the L&R speakers are set to "Large", which will probably happen automatically when it knows there is no sub.

Well this seems like a good place to start because it was basically set that way via the receiver's auto-setup feature in the beginning. When I started trying to adjust speaker settings manually I switched the setting from "no subwoofer" to "use" because I thought the bass module and a subwoofer were the same thing; I guess they're not from reading these replies. I also switched the L&R speakers from large to small (because they seemed small to me); I assumed it was an error. I'll go back in and switch the setting to no subwoofer and switch the speakers back to large. Why do they need to be set to large by the way? Should I also set the surround speakers to large also or leave them as small? My receiver is a Yamaha RX-V377.

Its sounding like I shouldn't really expect much at all from those bass modules, then? I would like to have some decent sounding bass with the system. With that said, could anyone recommend a decent starter level subwoofer that is priced towards the low end? I appreciate all the responses and feedback; I've learned (I think) a lot already.

 

[David Norman]

Large vs small is less a size issue than a frequency response issue. Depending on how the receivers processor is set up if the speakers are set to small, then all frequencies below 100/200 hz may be cut off since the system expects the low frequency to be handled by a subwoofer so why overload speakers that aren't meant to play those frequencies. :"Large speakers" suggest those speakers are designed for Frequency down to a double digits (10/20/40/60) -- how well they can handle those is another issue.


If the system system is working, it will likely sound perfectly OK. It will still likely sound better than most cheap soundbars and 10x better than any TV speakers. Since you aren't really expecting it to be an end all for a dedicated 100K Media Room don't worry about the rest. Bose speakers were generally meant to work with Bose receivers so I'm not sure how it meshes at all with the Yamaha receiver or how the signals know how to go to the proper positions since the Yamaha surely routes the signals differently than the way a Bose receiver would have

 

[schan1269]

You probably were taken. I've never heard of a Bose system that connects that way, with a bass module for the surrounds. It sounds like a cobbled together set from various mismatched systems. One of many problems with Bose systems is they usually cannot be mixed together.

That is how the 5 and 7 channel Blose connects. Always has back to the 90s.

OP

Blose sucks.

 

[JohnRice]

I'm not the least bit ashamed to admit I have limited experience with Bose multi-channel speaker setups. The ones I have seen had only one bass module, so I guess it's not entirely correct that they have always had two. Anyway, that's enough pointless nit-picking. I can't set foot in HTF without the same useless... um... "comments", from the same person.


Mathew, the reason you set it for no sub is because when you say there is one, all low frequencies are routed to the sub thorough a completely different connection on the receiver. In this case, that means those frequencies go nowhere, because nothing is connected to the sub output. If you do get a powered sub, then I'd probably set all speakers to "Small". Before someone nit-picks some things I didn't spell out, yes, there is actually a little more to it than that, and there are more variables, but I think that's all that really needs to be spelled out to get across the information you actually need to address your problem.

 

[Joel Fontenot]

I'm not the least bit ashamed to admit I have limited experience with Bose multi-channel speaker setups. The ones I have seen had only one bass module, so I guess it's not entirely correct that they have always had two. Anyway, that's enough pointless nit-picking. I can't set foot in HTF without the same useless... um... "comments", from the same person.


Mathew, the reason you set it for no sub is because when you say there is one, all low frequencies are routed to the sub thorough a completely different connection on the receiver. In this case, that means those frequencies go nowhere, because nothing is connected to the sub output. If you do get a powered sub, then I'd probably set all speakers to "Small". Before someone nit-picks some things I didn't spell out, yes, there is actually a little more to it than that, and there are more variables, but I think that's all that really needs to be spelled out to get across the information you actually need to address your problem.

I agree. I don't know much about Bose, but doing a quick look up, it almost seems like you got a cobbled set - I couldn't find which Acoustimass model yours matches with. All I could find were setups with only one bass module. All 6 satellite cubes are tied into it. Later models were powered and had a dedicated subwoofer connector for that output on the receiver. I could have just missed your particular model.


Is there a model and series number on the back of the bass module? There are pdfs of the manuals all over the internet for these things. Even on the Bose website.


If your bass module is unpowered (no power plug), then what you have is basically considered a "full-range" speaker set taken as a whole. That's why you should set your speakers to "Large" on the receiver. That way, the full frequency range of the sound is sent to the whole set. The speakers themselves then separates the frequncies it as it needs - the bass module takes the bass, then the crossover within the module sends the mid and high frequencies to the rest of the cubes. The receiver only needs to treat them as full range speakers on all channels.


The subwoofer output is ignored in this instance. The receiver just sends all the .1 LFE channel information into the front channels when there is no subwoofer connected. It's been a while since I've messed with my Yamaha, but you may have to turn the subwoofer off in the settings if it doesn't do it automatically.


Bose very well could have made a set with two bass modules since a true 5.1 setup does have bass frequencies in the rear channels too. It would be easier to sum the front channel bass into one speaker separately from the rear channels which could be summed in a separate bass module.

 

[Mathew Crow]

Thanks for the feedback everyone. I did some research on the Bose website trying to figure out how this configuration came about. My conclusion is that it started off as a 2.1 system with the front left, right, and center speakers. It turns out that back then at least (around 1995-2000) that you could buy an additional 5.1 module to expand your 2.1 system that included the rear left and right surrounds but it also came with an additional bass module because the original 2.1 system bass module didn't have the additional connections in it for the rear speakers.

Anyway, I set up the speakers per the suggestions in the thread and I'm pretty happy with it. The bass still seems non-existent almost, but I can live with it I guess. I only effectively paid $100 for the speakers so I figure I got my money's worth. I might want to replace them someday but at least now I have something which is better than nothing. If anyone wants to suggest a better entry level 5.1 speaker system I'm very open to your suggestions. Maybe I could ask Santa for it soon.

I appreciate all of your advise and feedback, thanks again.

 

[JohnRice]

Just to clarify your system. There is no ".1" to it. .1 refers to a subwoofer, which you don't have. Your front speakers are just a 3 channel set, that needs the bass module to produce what little bass you get, but that's not an actual ".1" bass channel. You can add a subwoofer to the speakers you have.

 

[Mike Frezon]

If anyone wants to suggest a better entry level 5.1 speaker system I'm very open to your suggestions. Maybe I could ask Santa for it soon.

Matthew: Welcome to the HTF!


I have been a strong proponent of the entry-level Onkyo systems. My 25-year old son has had one for awhile now and I think it sounds terrific for the price.


One of the great things about it is that all the parts are upgradeable/replaceable. If something stops working (or you have an urge to improve things) you can do it piece by piece--something that Bose doesn't allow (all proprietary parts).


HERE'S a LINK to one of the current systems on Amazon. You might find you can get a better price on last year's model and be just as satisfied (depending upon your needs). Just be certain that the system has a powered subwoofer.

 

[Member 384960]

Plot twist: The acoustimass modules are actually working fine. You think they aren't because the drivers in them aren't big enough to produce loud and low bass like a real subwoofer.

 

[Nelson Au]

I just found this thread, I don't know if the original poster is still here or watching, but I actually have two Bose Accoustimass systems. I bought mine in the 1990's for my first home theater setup. I know a lot of people make fun of Bose. At the time as I do now, they are connected to a NAD receiver and I use it in my home office. My main system now has B&W 804s speakers with 805's prior to that. Obviously I hear a huge difference.

But back to the OP's question. I have my Accoustimass 2 channel system set up in my home office, I connected the left and right inputs into the bass module and the left and right outputs go to the cubes. I set up the bass module in a corner and I'm getting quite good bass response, really impressive actually. And my NAD is set flat and bass EQ button is engaged. It boosts bass a little. Dire Straits Dire Straits album is one I'm listening to a lot on both systems and of course it's going to sound really involving on my main system. But on the NAD Bose set-up, it is listenable. Good bass output. Highs are good. Midrange is where everyone says Bose falters and it's not as good as my main system. But I can live with it in the office. I also have the 3 channel Bose Acoustimass set up with left right and center connections on the bass module. I had tried to use both bass modules in the home office setup so using one for left and one for right. It didn't really improve it that much, so I simplified it and went back to the 2 channel set up with one Accoustimass set up.

At first, when I got the system, I heard no bass or very little. I found out I reversed the plus and minus connections. Once corrected, it was brassy.