Hi Everyone!
I'm getting a little serious about building the bass cabinets for my existing 2-way speakers. If possible I'd like to restrict comments to the general dimensions and part selection. Somehow when we talk subwoofers things go far off track and not wanting to debate here how my living room will be set up. Thank you. 😉
The idea is that I have rather large "bookshelf" speakers using an AMT tweeter and 7" mid-woofer. I'd like to convert the existing 2 way, passive into 3-way fully active by replacing their existing stands with a "powering subwoofer." That is, a subwoofer with built-in 3-way plate amplifier.
Parts:
Woofers - 2x Dayton Audio RSS265HF-8 10" 8 ohm subwoofers. Suggested by another DIYer, thank you very much.
Amp - Hypex FA 123 - 3 Channel (2x125W + 1 x 100W)
Cabinet: Sealed. Ported is just too big.
General dimensions are 27" tall, 13.5" wide and about 15" deep at the top, 17" deep at the bottom. IMHO, the depth is the most adjustable dimension, but it can't be too shallow or the 2-way won't fit right.
I've gone back and forth thinking about using just 1 woofer, but then the volume then is too large.
Above the plate amp will be 2 pairs of binding posts to connect directly to the drivers in the bookshelf. I won't be building the cabinet, I leave that up to Solen in Canada. They do a great job.
I'm getting a little serious about building the bass cabinets for my existing 2-way speakers. If possible I'd like to restrict comments to the general dimensions and part selection. Somehow when we talk subwoofers things go far off track and not wanting to debate here how my living room will be set up. Thank you. 😉
The idea is that I have rather large "bookshelf" speakers using an AMT tweeter and 7" mid-woofer. I'd like to convert the existing 2 way, passive into 3-way fully active by replacing their existing stands with a "powering subwoofer." That is, a subwoofer with built-in 3-way plate amplifier.
Parts:
Woofers - 2x Dayton Audio RSS265HF-8 10" 8 ohm subwoofers. Suggested by another DIYer, thank you very much.
Amp - Hypex FA 123 - 3 Channel (2x125W + 1 x 100W)
Cabinet: Sealed. Ported is just too big.
General dimensions are 27" tall, 13.5" wide and about 15" deep at the top, 17" deep at the bottom. IMHO, the depth is the most adjustable dimension, but it can't be too shallow or the 2-way won't fit right.
I've gone back and forth thinking about using just 1 woofer, but then the volume then is too large.
Above the plate amp will be 2 pairs of binding posts to connect directly to the drivers in the bookshelf. I won't be building the cabinet, I leave that up to Solen in Canada. They do a great job.
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You going to be using these for HT at all? If I am reading this right is 125 Watts enough for the sub's? You going to use any +Eq? You are going sealed so I don't see how you can avoid it.
Rob 🙂
Rob 🙂
Hi Rob,
Yes, mixed use. Yes, it's 125W/4 Ohms for the two larger sections. I'm going to use 8 Ohm drivers in parallel, so efficiency of around 87 dB/W. With 100 Watts that would get me to 107 dB. If I go up a model to the FA253 with a 250 W amp I only gain 3 dB of headroom, not really worth it.
Yes to EQ, built in feature of those plate amps. Based on the current bookshelves, there is a lot of room gain.
I will be using these in addition to a dedicated subwoofer for HT.
Also keep in mind that I will be using one such cabinet per side, so total of 4 x 10" drivers and 2x 125W amplifiers for a modest (14' x 20') living room, no?
I'm currently using a stereo integrated (110W/channel) driving smaller two-ways. These plate amps, plus active filtering and 4 new drivers will add a huge amount of output and dynamic range to a system I rarely push over 2 watts. 🙂
I should add that a big reason for this plate amp is the ability to re-think/re-work my bookshelves. I will be taking full advantage of the digital delay and EQ features as well as crossovers when I redo the entire system. The original design used 2nd and 3rd order filters with rather mild slopes. I'm looking forward to trying out LR4 across the board.
I realize now that in calling this a subwoofer (which it is) many readers will expect me to try to get to 16 Hz anechoic. I'm really not going for that. 30 Hz with plenty of headroom. Maybe I should have called it a powering woofer cabinet instead! 🙂
I realize now that in calling this a subwoofer (which it is) many readers will expect me to try to get to 16 Hz anechoic. I'm really not going for that. 30 Hz with plenty of headroom. Maybe I should have called it a powering woofer cabinet instead! 🙂
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I didn't have my glasses on and I thought you said "use them plush" 🤣 I imagined a carpet covered cabinet.
Anyway, hmmm??? 2 woofers per cabinet, wired in parallel, both facing the same way is the plan.
Dave's zeal for cabinet vibration reduction seems to ignore the polar ramifications.
The latitude in the woofer to mid crossover range afforded by front facing, rather than side facing woofers would outweigh the reduction in cabinet vibration that configuration affords.
27" seems low for a stand height, are your mid/high cabinets also angled upwards?
Art
Wnat polar ramifications? It is a subwoofer. Pretty much anyway you put the woofers te polars are the same.
dave
As you may recall, I originally thought about putting the woofers as close to the floor as possible, and did think about side firing, but the magnets get awfully close to each other in this width.
Let me recheck the height. There are existing stands there now which are a little lower than that. This would move the speakers up a little putting my ear closer to midwoofer axis. These are the speakers that go on top. I've been sitting on tweeter axis but really prefer to sit lower for best sound.
Let me recheck the height. There are existing stands there now which are a little lower than that. This would move the speakers up a little putting my ear closer to midwoofer axis. These are the speakers that go on top. I've been sitting on tweeter axis but really prefer to sit lower for best sound.
With these drivers and dimensions I think I am locked into both in the front.
Front and back wont work due to length of plate amp.
Sides wont work due to lack of internal clearance
Front and back wont work due to length of plate amp.
Sides wont work due to lack of internal clearance
Looking a little at prior art on box simulations, it seems a ported box has significantly better bass, 23 Hz vs. 40 Hz or so. In this cabinet size, I can switch to a single woofer and get more bass at the cost of significant loss of output per volt.
What would you do in a 14' x 20' room?
What would you do in a 14' x 20' room?
There is the RSS265HO-44, and that has more output over a single RSS265 if you run them in parallel. I think the Hypex is 2 ohm stable, and you could wire the HO-44 in parallel.
Depends on the room and the goals.
You know my thoughts and position on subwoofers…..I’d instead build 4 single driver cabs and place them in all four corners…..you’ll wind up with a +/-3b response with a simple medium Q filter.