8 or 10" subs for sealed venture?

[shrubs]

I'm putting another 2.2 sub setup together. - two mains + two subs. My Dynaudio upper middle tier stand mounts don't miss bass notes they play the whole spectrum really well. I'm currently running 250 clean watts to each stand mount in 4 ohms.

The listener is needing more impact. While avoiding damage to my loved Dynaudios. I'd like to feel the sonic waves more while listening.

I have a two channel class D Crown xls, but I have not chosen subs.

Peerless 10" worked well in two sealed applications. But I also employed sealed 8's that I was happy with.

I'm pondering twin 8's (two per box in left and right channel sub).

8 ohm in parallel for two 4 ohm loads. Pretty basic straight forward configuration.


Unless there are some good 8s out there since I've played with subs. That are high power handling but not necessarily high dollar and hard on the wallet. Perhaps I would be happy with single 8s?

In terms of sound I could use a little guidence wich direction to go. I'm leaning towards 8s. I do like the thought of twins in separate boxes.

Speaking of such a design, would I get better performance if I were to separate the boxes inside to make 2 equal sized chambers effectively making each sub box "two channel"?

Or is there no benefit compared to twin subs sharing one entire sealed box, without obstruction, no channel divider.

 

[planet10]

I like the CSS SDX10.

But i alos prefer push-push subs due to the dramatic reduction in box load so would likely choose 2 8s over 1 10.

dave

 

[shrubs]

I had a BPS Mirage with dual 8's going back 7 or 8 years. Theyre performance is pleasing. The earlier models are sealed (wich I do prefer) the later bps "i" version is ported, and does not sound as crisp and precise. They were one of the first to offer them commercially then came Miller & Kriesel bi polar subs.

 

[waxx]

The Dayton RSS210HF-4 is also a very good candidate and relative cheap. Idem with the
SB Acoustics SB23MFCL45-8.

 

[MrKlinky]

There is rarely any good reason to use multiple smaller driver units for a sub other than packaging restrictions. Always use the largest drive unit possible. Move a lot of air - GENTLY!

 

[TKO956]

I've been using the sealed Kairos Bass module from Jeff Bagby for several months and have been very happy. These use the SB Acoustics SB29NRX75-06. The write-up for these speakers can be found several places including here

 

[shrubs]

Thanks for sharing those thoughts.

Id like to keep cost at or under $200.00 Canadian per subwoofer driver.

I might go ahead with 2 separate closed boxes with a single 8" per box. I will investigate other designs some time in the new year.

What do you think of these DS 8s? DS18 EXL-X8.2D 8" Cast Frame DVC Subwoofer 2 Ohm

I'm willing to try Dayton or SB Acoustics with some help choosing an appropriate model 8" $150 - $200 range.

Dayton Audio UM8-22 8" Ultimax DVC Subwoofer 2 Ohms Per Coil

I'm only considering subs that shine in sealed boxes please.

 

[planet10]

There is rarely any good reason to use multiple smaller driver units for a sub other than packaging restrictions.

Except that using pairs of drivers push-push brings significant advanrages over a single driver a size larger. It all comes down tot he physics. Active reaction cancelation is a significant gain in a woofer.

dave

 

[WhiteDragon]

Not to take things completely off your map.

But I am, cause even some of the budget Dayton drivers are real performers.

To get low extension in sealed you have to drift into 12" territory.


But the budget 12" classic
Dayton Audio DCS305-4 12" Classic Subwoofer 4 Ohm

Some guys just want detail , accurate music and appreciate sealed
But I also like subs that have more detail above 100 Hz

with basic copper ring technology Dayton seems to pull off some good sounding subs
even at a budget, and the 4 layer coils seem to hold up to power, much like more expensive models.

8" speakers will put you in 82 to 84 dB territory, so using 2 is feasible to help with sensitivity up to around 85 to 87 dB

I often sneak up to 12" drivers cause sensitivity shoots right up to 88 to 90 dB
with one driver. And Fs is lower

Again the detail is just there and not to power hungry.

 

[waxx]

Not really true, i do it with a 10" scanspeak 26W8534G00 (89dB sensitive) in a big sealed cab of 77L with an F6 of 30Hz and got real performance till more than loud enough for my living room. And many do it smaller with good drivers. With modern subwoofer drivers this is not the case anymore like it used to be.

 

[shrubs]

I concur (re small diameter subs). Small drivers are capable of reproducing the low tones very well. As I was saying nearer the top my Dynaudios go low enough, they house 6 1/2" drivers in stand mounts. They perform great but of course they can not offer the slam that subwoofers can. If I'n not happy with 8"s I can easily bump up to 10s.

The Dynaudios seem to be in a class of there own. Of course not all stand mounts are created equal. In fact I have not owned or heard small monitors that reproduce bass as well as these do. PMC comes to mind, they do pretty well with some of they're mini transmission line stand mounts. The previous checked off more boxes, bass mids and highs. I'm glad I went with them instead.

Thanks for pitching in.

 

[MrKlinky]

Except that using pairs of drivers push-push brings significant advanrages over a single driver a size larger. It all comes down tot he physics. Active reaction cancelation is a significant gain in a woofer.

dave

I cannot argue with the physics, but what effect will this have on the sound in reality?

 

[planet10]

You will get more uniform omnidirectional pattern, but mostly it does a really good job of taking energy out of the cabinet. The Twin SDX10 woofers we did were 15mm BB. It was sufficient.

dave

 

[cowanaudio]

I'd use the SB23MFCL45-8 in this application. They will be loafing while the Dynaudios are struggling to keep up.

 

[shrubs]

Not surprising cowanaudio since the Dynaudios are not subwoofers.

 

[cowanaudio]

Hopefully you'd relieve the Dynaudios of bass duties, and leave that to the twin 8s per side.

 

[shrubs]

They take a lot of clean power. I have more power on tap then what would be wise to use. I make it to 9 oclock 10 at the most. With loud clean recordings. Amp is Mark Levinson putting 250 wattsx2 @4 ohms. There capable of playing very cleanly and much louder than what's comfortable (or safe) for human hearing. I leave tones @ flat on my preamp when I do lean on them. Its plenty enough to feel intense sonic waves physically but enough never seems to be enough after I became used to them. The increases of bass isn't needed per say as I was saying. Its more of a want urge thats pushing me towards subs.

This page touches on why they do bass tones so well. Although mine are the larger 20s. I also have a pair of the largest bookshelf's from the Audience line. Both of them reproduce bass extremely well. Dynaudio Emit M10 review | What Hi-Fi?

I'll find the article I was after given more time. It goes into more detail as to why small Dynaudios are so good at bass.

 

[techtool]

Speaking of such a design, would I get better performance if I were to separate the boxes inside to make 2 equal sized chambers effectively making each sub box "two channel"?

Or is there no benefit compared to twin subs sharing one entire sealed box, without obstruction, no channel divider.

I've had similar questions and couldn't find much info on the subject, so I decided to give it a try in a recent build. Not a sub, but the principle is the same. The project was an MTM design with two 8" mid-bass drivers in a cabinet with identical sealed chambers. The tweeter is mounted on the outside so it does not disturb the symmetry (more details in my post #3443 in Multi-way / System pictures and description).

My reasoning for the isolation was that, due to typical manufacturing tolerances, the two drivers are not going to be 100% identical, acoustically or electrically, so to avoid any unbalanced interaction between them, better to isolate. Electrical isolation comes from a dedicated amp channel for each driver. They do sound very good, with excellent bass detail. And the internal isolation wall also increases cabinet rigidity, always a good thing.

 

[rhapsodee]

Throwing the idea out there. If the room layout is able to support it, having dual 8 per side, one above and one below the dynaudio bookshelf is beneficial in smoothing the bass with vertically distributed sources. Something like the Frank tower sub.

https://hifi-unlimited.blogspot.com/2020/12/hot-news-frank-ab-2-tower-sub.html?m=1
If the room dimensions work out, it is almost a 4 driver SBA on the front wall.