Bose Frankenstein Sound System and it's issues

NewbGuy77

Standard Member
Yes, that looks like shielded cable.

There should be a thin "drain" wire - an unjacketed wire running along with the foil shield. Connect the outside of the phono plug to this and the inner to any one of the other cables.
Yes, i know what "drain" wire you are speaking off. It's not too clear in the pics but its definitely there.

Being a big newb can you clarify what type of Phono Plug are you talking about? Is that basically an RCA adapter? My results for phono plug adaptor is varying quite a bit.
 

NewbGuy77

Standard Member
@noiseboy72 I'm sorry for the extensive questions but I'm a dunce. I'm wondering if you can confirm that I'd connect the black wire, to the "drain" wire rather than one of the other speaker wires? What difference does it make? What does the "drain"wire do?

1625091736730.png


On the subwoofer previously I'd just use an RCA y-splitter to use the RCA R/L inputs on the sub. I'm a bit confused by the Sub's speaker level inputs with the R/L. it's a sub so it's just single input right? Does it make a difference whether i use the RCA R & L inputs or the Speaker Level Inputs R or L?

1625092749643.png
 

noiseboy72

Distinguished Member
Ok, no worries.
In order to reduce the likelihood of interference - hums and buzzes getting into the cable, we need to use the screen. The drain wire is connected to the screen and needs to be connected to what would be the screen on the RCA connector. The signal can then be carried on any conductor that runs within the screen, so just pick any colour for this, as so long as you use the same one at each end, all will be good.

Your sub has various connection types, so it can be confusing to work out the right one. The left and right inputs are for when you are connecting to a system without a sub output. This can either be directly from the amplifier via a pre-out or connected via the speakers using the speaker connections. As you have a dedicated sub output from your amplifier, you don't need to worry about this and just connect to one terminal.

The rca inputs will be a direct connection into the sub amplifier, while the speaker inputs will be isolated, so that they don't affect the other speakers if the sub is connected. You may find that if once you connect this up using the rcas at both ends, you get an earth loop hum - a continuous hum rather than interference. If this is the case, you could try using a speaker connection on the sub instead of the RCA and see if this improves things. Depending upon the type of isolation the sub uses, this could well cure the problem.

Try it out and report back!!
 

NewbGuy77

Standard Member
I received the center speaker the other day and reset up the system. I'm waiting for the rca adapters to get to me before I can set the sub in there. I will be looking to set up everything with banana plugs as well for future convenience. I suspect eventually I'll upgrade the AV Receiver with a 4k one but I'm in no immediate rush for that.

So far, the difference between having a Bose L/C/R speakers versus having the Polk S20's and S30 for L/C/R is absolutely tremendous. The sound clearly harmonizes way better between the front and rear speakers and it just sounds "fuller" and "fills" the space up how I always hoped that it would. We get great projection and clarity from movies and music without having to crank up the volume so much. I'm very pleased with the S30 in it's handling of voices and I'm very happy i went with that over the S35. My wife and I listened to a few songs last night and even she could tell there is a huge difference now. There was a song with some piano parts that especially stood out to us in how vibrant the piano was.

I never was one to bash on Bose as the speakers previously had sounded good to me and i didn't think i could really hear the difference but I absolutely do now. I do think if we had the entire Bose system set up it'd probably would have balanced out a bit more and maybe it wouldn't have felt as noticeable as it was. But jeez it's a huge difference. The prior "frankenstein" setup was absolutely anemic and i still haven't got the sub woofer set up yet. I will report back once I do in the next day or two.

special thanks to @Gasp3621 and @noiseboy72 for all your help!
 

NewbGuy77

Standard Member
Ok, no worries.
In order to reduce the likelihood of interference - hums and buzzes getting into the cable, we need to use the screen. The drain wire is connected to the screen and needs to be connected to what would be the screen on the RCA connector. The signal can then be carried on any conductor that runs within the screen, so just pick any colour for this, as so long as you use the same one at each end, all will be good.

Your sub has various connection types, so it can be confusing to work out the right one. The left and right inputs are for when you are connecting to a system without a sub output. This can either be directly from the amplifier via a pre-out or connected via the speakers using the speaker connections. As you have a dedicated sub output from your amplifier, you don't need to worry about this and just connect to one terminal.

The rca inputs will be a direct connection into the sub amplifier, while the speaker inputs will be isolated, so that they don't affect the other speakers if the sub is connected. You may find that if once you connect this up using the rcas at both ends, you get an earth loop hum - a continuous hum rather than interference. If this is the case, you could try using a speaker connection on the sub instead of the RCA and see if this improves things. Depending upon the type of isolation the sub uses, this could well cure the problem.

Try it out and report back!!
So i tried connecting the sub a few different ways.

First i tried connecting the shield/drain wire to black, then the in wall red wire to the red on the RCA adapter on the AV receiver side. On the sub side i connected the in wall wires directly to the wire input on the sub without the RCA adapter. The sound output seemed very low even with the sub blasted to the max. The Audyssey settings all seemed off as well.

Then i tried connecting the RCA adapter on the receiver side with the black speaker wire in my wall, and the red to the red ( so I avoided connected to the shield bare wire ). Then I connected the RCA adapter to the sub in the same way. The output on the sub was way stronger and I had to lower the settings on the sub to 50%. However, i noticed EXACTLY what you said after pausing the scene i was testing with. After a few moments there was a hum/noise on the sub after awhile of no input from the AV Receiver. It was pretty noticeable even on the lower settings.

Then i tried connecting again to the shielded wire with RCA adapter on both the amp side and the sub side. And it was perfect. No noise or hum when there is no input on the AV receiver. I'm not sure if it was maybe just my connection but it seems the RCA input is much more powerful than just the speaker wire.

Once i got the sub situated the results on the audyssey tone tests came back as I had hoped but i had to change the Denon Setting of the LPF to "LFE+Mains" with a crossover at 120hz. In the past i noticed if i put this setting just to "LFE" i barely get any subwoofer at all. I'd have either too much woofer or too little and could never get it right. The individual speaker crossovers to 40hz cutoff for my front speakers and my in ceiling surrounds at 60hz cutoff. I'm still undecided whether i will bump the crosssovers up a little bit or not. I know the THX settings usually 80hz cutoff across all speakers. But overall, I'm very happy with the results. I may leave it with the Audyssey results. It sounds pretty well balanced to me as of now. Although at times i think I'd like a little bit more subwoofer. That's usually always the case tho.

Thank you very much @noiseboy72 I wouldn't in a million years ever thought to connect to the "drain" shielded wire.

Now all I need to do is build a box to hide the sub and I need to try to get the right wall plates to connect the speaker wires so I don't have these ugly open wall plates with speaker wire coming out of them. I'm still not sure if i should put the RCA adapter near the sub inside the wall, and then put the wall plate as a RCA port, or put it as as two banana plugs then, connect them via RCA adapter near the sub and amp. I lean toward the former.

Eventually i'll need to put a hole behind my tv to make sure i can hide cables from my receiver to my TV. For now i can hide them behind the rather large S30 center speaker.
 

Gasp3621

Distinguished Member
So i tried connecting the sub a few different ways.

First i tried connecting the shield/drain wire to black, then the in wall red wire to the red on the RCA adapter on the AV receiver side. On the sub side i connected the in wall wires directly to the wire input on the sub without the RCA adapter. The sound output seemed very low even with the sub blasted to the max. The Audyssey settings all seemed off as well.

Then i tried connecting the RCA adapter on the receiver side with the black speaker wire in my wall, and the red to the red ( so I avoided connected to the shield bare wire ). Then I connected the RCA adapter to the sub in the same way. The output on the sub was way stronger and I had to lower the settings on the sub to 50%. However, i noticed EXACTLY what you said after pausing the scene i was testing with. After a few moments there was a hum/noise on the sub after awhile of no input from the AV Receiver. It was pretty noticeable even on the lower settings.

Then i tried connecting again to the shielded wire with RCA adapter on both the amp side and the sub side. And it was perfect. No noise or hum when there is no input on the AV receiver. I'm not sure if it was maybe just my connection but it seems the RCA input is much more powerful than just the speaker wire.

Once i got the sub situated the results on the audyssey tone tests came back as I had hoped but i had to change the Denon Setting of the LPF to "LFE+Mains" with a crossover at 120hz. In the past i noticed if i put this setting just to "LFE" i barely get any subwoofer at all. I'd have either too much woofer or too little and could never get it right. The individual speaker crossovers to 40hz cutoff for my front speakers and my in ceiling surrounds at 60hz cutoff. I'm still undecided whether i will bump the crosssovers up a little bit or not. I know the THX settings usually 80hz cutoff across all speakers. But overall, I'm very happy with the results. I may leave it with the Audyssey results. It sounds pretty well balanced to me as of now. Although at times i think I'd like a little bit more subwoofer. That's usually always the case tho.

Thank you very much @noiseboy72 I wouldn't in a million years ever thought to connect to the "drain" shielded wire.

Now all I need to do is build a box to hide the sub and I need to try to get the right wall plates to connect the speaker wires so I don't have these ugly open wall plates with speaker wire coming out of them. I'm still not sure if i should put the RCA adapter near the sub inside the wall, and then put the wall plate as a RCA port, or put it as as two banana plugs then, connect them via RCA adapter near the sub and amp. I lean toward the former.

Eventually i'll need to put a hole behind my tv to make sure i can hide cables from my receiver to my TV. For now i can hide them behind the rather large S30 center speaker.

Nice to hear you got it working! It should be on LFE mode and LPF for LFE 120hz. Also bump those crossover settings for speakers at least to 80hz, they should sound better that way! No reason to play such low as the sub does it much better with larger driver and own amp.
 

NewbGuy77

Standard Member
Nice to hear you got it working! It should be on LFE mode and LPF for LFE 120hz. Also bump those crossover settings for speakers at least to 80hz, they should sound better that way! No reason to play such low as the sub does it much better with larger driver and own amp.
I thought my crossover settings seemed a bit low. I probably will bump them up. However, When i listen to music on "LFE" only mode there would be like no subwoofer? I heard thats because music is recorded in stereo without a .1 audio track like in movies. Perhaps, i need to mess with it a bit more.
 

noiseboy72

Distinguished Member
Glad its all working for you. :)

80Hz and upward is about where you can start localising where the bass is coming from. It is also that "slam" frequency that starts to give music impact. Setting it as your crossover frequency is not a bad idea as it will add a lot of perceived weight to music and effects that go that low.
 

NewbGuy77

Standard Member
Glad its all working for you. :)

80Hz and upward is about where you can start localising where the bass is coming from. It is also that "slam" frequency that starts to give music impact. Setting it as your crossover frequency is not a bad idea as it will add a lot of perceived weight to music and effects that go that low.
I updated the system to 80hz crossover and purely LFE for the time being. If i had the setting as LFE with my front speakers selected as Large-- i would get no subwoofer on music tracks. Switched speaker setting to small and it seems to be working correctly. Sounds good so far.

Wallplates get here soon so i can hide my wires. I'm probably going to end up putting the RCA adapter inside my wall and connect it to this wall plate i ordered.
1625689268555.png


Then subwoofer box next.
 

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