HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

Has anybody here ever built a speaker with left and right mid bass sharing the same backwave enclosure space ? Like some little boombox and Bluetooth speakers do.

I can't see stereo separation being a problem as the left and right are very close to each other anyway. If one channel has a low frequency event and the other doesn't then obviously the one that does will make the other output that as well. Is that really a problem for such a thing.

Maybe the midrange will bleed through the other drivers as well (out of phase) but as there is no stereo separation anyway then what's the problem ? Separate tweeters are easy and don't take up any interior volume but do require exterior real estate.

I tried mixing stereo to mono af line level (using part of my resistor based potential divider but wasn't happy with the result. These new Bluetooth speakers like my jbl charge 5 really do pull it off extremely well but most have little passive radiators.

I had an idea to build both stereo speakers in one large enclosure using 5.25 or 6" mid bass and a few tweeters or small full range drivers. Not exactly portable but I could put it on wheels. Having no stereo separation doesn't bother me, infact when I tried my speakers right next to each other I preferred it No need for passive radiators either if the thing uses big enough mid bass.

Need to think a bit more about this.

I reckon that even thinking about this has made the tiny amount of audiophile street cred that I had remaining totally evaporate. Oh well. It's all about the enjoyment of music after all isn't it ???

My little jbl charge 5 does so many things right. If is really detailed and non annoying. The bass is limited of course and the ample bass it has is mostly produced by the two small passive radiators, one on each end.

Stereo is starting to really piss me off largely due to a hearing imbalance I suspect I suffer from. I also don't like the way some recordings place instruments. When I tried my bipolar speakers away from all walls and pushed right up to each other I absolutely loved the result. Is there something wrong with me?

All the sound coming from one place clears up some annoyances I have like crap recording sound staging and my suspected ear imbalance. Another thing it helps with is when you are sat nearer one speaker the farther away speaker gets swamped and the stereo image is wrecked. Place the two speakers in one cab and this is not a problem anymore. Sit anywhere and you get both channels at the intended relative volumes.

Fook hifi and stereo. Why o why did mono get dropped

karatestu wrote: ↑Sat Oct 16, 2021 4:10 pm Has anybody here ever built a speaker with left and right mid bass sharing the same backwave enclosure space ? Like some little boombox and Bluetooth speakers do.

No. But my bass cab for low bass (cross over at 70Hz) does.
In fact left and right low bass share the same speaker cone! :-D
(Separate voicecoils on the DVC bass driver of course.)

To avoid sharing cabinet volume issues altogether, and drawing inspiration from the old 3 way Goodwood Magister, I have used close back midrange drivers higher up the frequency range.
Pyle do affordable 5 and 6 inch sealed basket drivers (PDMR5 and PDMR6). You could play around with those. (I replaced the original sealed midrange in a pair of Magisters with the 5 inch Pyle one.)
Monacor do a similar 5 inch sealed basket (the SPP-125) which is a few quid more than the Pyle equivalent and IMHO vastly superior (I think they use the same closed basket). I used the Monacor one in a large 3 way DIY build.

In both cases the sealed 5 inch drivers were handling 800 - 5000Hz IIRC, which they were happy with. I suspect both would have struggled going a lot lower than that. You can get larger sealed back drivers, but I've never tried those. As one goes down the frequency range I can't imagine completely eliminating cabinet volume is anything other than a sonic drawback.

Docfoster wrote: ↑Sun Oct 17, 2021 12:40 pm

karatestu wrote: ↑Sat Oct 16, 2021 4:10 pm Has anybody here ever built a speaker with left and right mid bass sharing the same backwave enclosure space ? Like some little boombox and Bluetooth speakers do.

No. But my bass cab for low bass (cross over at 70Hz) does.
In fact left and right low bass share the same speaker cone! :-D
(Separate voicecoils on the DVC bass driver of course.)

To avoid sharing cabinet volume issues altogether, and drawing inspiration from the old 3 way Goodwood Magister, I have used close back midrange drivers higher up the frequency range.
Pyle do affordable 5 and 6 inch sealed basket drivers (PDMR5 and PDMR6). You could play around with those. (I replaced the original sealed midrange in a pair of Magisters with the 5 inch Pyle one.)
Monacor do a similar 5 inch sealed basket (the SPP-125) which is a few quid more than the Pyle equivalent and IMHO vastly superior (I think they use the same closed basket). I used the Monacor one in a large 3 way DIY build.

In both cases the sealed 5 inch drivers were handling 800 - 5000Hz IIRC, which they were happy with. I suspect both would have struggled going a lot lower than that. You can get larger sealed back drivers, but I've never tried those. As one goes down the frequency range I can't imagine completely eliminating cabinet volume is anything other than a sonic drawback.

Thanks for that Doc. I didn't know such larger closed back drivers existed And I do love Monacor drivers, and Visaton- I must be part German or something

I will have a look at the SPP-125

Had a look. Big 10dB peak at resonance (550 hz). Sensitivity is 92dB which is good for a 5" Impedance is good too.

A very useful driver in the right situation. Not expensive enough to be taken seriously by the driver snobs though

I came across this large one cabinet active speaker available from Harrods for 12 big ones. Orbitsound Air D1.



https://www.whathifi.com/news/orbits ... er-system

https://www.orbitsound.com/en-gb ... /air-d1/

If I had money to burn then I would be on my way to Harrods right now.

Sorry to see you on a 'downer' Stu, you've put in so much hard work, please give yourself some time, I'm sure you can come up with something that will suit your listening style. If you do have an hearing imbalance, maybe dual volume controls can help, I can understand your frustration, I seem to have acquired a problem now with my ears, the best example I can give, on certain higher frequencies it sounds like the speakers are distorting, but that's a problem for another day.

I'm not on a downed as such Dave but my hearing issues sure are a pain in the ass. It probably explains why I am Hnever happy, despite any initial enthusiasm and my diy speakers never get finished. Wanting to try everythjng doesn't help either.

Thanks for your kind thoughts.