Small 3way speaker

[tpsorin]

Hello,

I plan to build a small 3way speaker. It will be used in a small room (3.5x3.5m). I am not sure if I want a standmount or floorstanding speaker, but I want to have narrow baffle.

I am now on driver selection:
Woofer: 1(2)x Seas L16RNX or 2x RS150
Midrange: Peerless HDS-106EXCL or Seas MCA12 or Vifa PL11MH
Tweeter: Vifa XT19 or Scan-Speak D2010

My prefference would be L16 + Peerless + XT19. I have only heard HDS-106EXCL and XT19. It is worth spending more for D2010?

Any other comments are appreciated.

I already have Dayton RS52 midrange, but I find the sound a little thin.

Thanks

[JonMarsh]

Do you have measurement equipment as well as design software? What does your RS52 design look like? It's a very flat, accurate driver, in my experience, very low distortion; I'm curious how you used it that you found the sound a little thin.

This is the raw measurement for the RS52 on the cabinet in the last project I did; of course, it's influenced by baffle step, just like the midwoofer is.




I've done one design with it that I'm quite happy with, and if someone asked me to do a small three way with it, I'd do a similar design but with one 6.5" woofer instead of two. Part of the trick is fitting all the stuff on the front panel of a "small" box.

Using a small factor tweeter with the RS52 might allow turning this into a three way.



The woofer in this case is a HiVi D6.8. I'd only recommend it if you wanted to get an exceptional bottom end out of a small enclosure; it's a few dB less sensitive than your typical mid priced 6.5" woofer, but you can do a very nice tuning in a 0.75" enclosure, with bottom end extending into the mid 30's.

One thing that makes doing a good "small" three way something of a challenge is the crossover network- assuming even just 2nd order networks, the crossover is about twice the size of that of a two way. That I haven't figured out how to get around or make smaller- which is why these are the smallest three way I've done. The crossover is split between four boars, attached to the rear part of the enclosure sides.



This is only 1 cu ft, which is not optimum for bass extension, but as the design was first conceived for center channel, that wasn't a design point. However, we found they made a really nice set of "mains" so to speak, and they're in my family room in that function.



Given the overall complexity of three ways, I probably wouldn't build anything smaller than this- if one is happy to settle for a small midwoofer and the limitations in bass output, then a reasonable two way design is much simpler to manage in a small enclosure, and can achieve a nice smooth overall response.

Modula MT

There are many other designs posted in our Missions Accomplished sub area; and check out Zaph's designs, too- he's something of a specialist in varieties of two ways.

Zaph Audio

[tpsorin]

Do you have measurement equipment as well as design software? What does your RS52 design look like? It's a very flat, accurate driver, in my experience, very low distortion; I'm curious how you used it that you found the sound a little thin.

Measurement equipment: Behringer microphone ECM8000 + PC
I have used it with a 8" Beyma woofer Seas 27TDC tweeter (I had this drivers from another project). I have also tried Monacor DT-25T tweeter; nice visual match.
Crossover is LR2 at 800 and 4200Hz.

Response is flat, ~3dB BSC (this works well in my room). Sound is clear, very detailed but something is not right. The woman voices are perfect, the man voices on the other hand are not right.
I don't know, maybe it is crossover, or maybe woofer is not a well match for RS52. The same woofer with poly mid crossed at 400Hz/2400Hz gives me very good male voices.

I see in your graph that RS52 response is few dB down from woofer response.

One thing that makes doing a good "small" three way something of a challenge is the crossover network- assuming even just 2nd order networks, the crossover is about twice the size of that of a two way. That I haven't figured out how to get around or make smaller- which is why these are the smallest three way I've done. The crossover is split between four boars, attached to the rear part of the enclosure sides.

Another way is to make the box few cm taller and to have a compartment at bottom only for crossover.

This is only 1 cu ft, which is not optimum for bass extension, but as the design was first conceived for center channel, that wasn't a design point. However, we found they made a really nice set of "mains" so to speak, and they're in my family room in that function.

Interesting design. I am sure it sounds very good.
I never heard HiVi; and I am not sure that I will: it is at the same price of Seas prestige here. ANd 2x the price of Dayton RS.

Given the overall complexity of three ways, I probably wouldn't build anything smaller than this- if one is happy to settle for a small midwoofer and the limitations in bass output, then a reasonable two way design is much simpler to manage in a small enclosure, and can achieve a nice smooth overall response.

I remember some old bookshelf speakers with 1" + 4" +8". The midrange was excellent. I guess, I can get the same with 2way speaker if I use better drivers. Bass is not so important.

There are many other designs posted in our Missions Accomplished sub area; and check out Zaph's designs, too- he's something of a specialist in varieties of two ways.

Yes. I know. But where is the fun if I copy other designs?
I may copy one design just to have a sound reference. Zaph ZDT 3.5 but with only one woofer, no BSC, would be just perfect.

[JonMarsh]

Hmmmm...

Just some thoughts...

Female voice is in a range with higher fundamentals than male... reducing BSC to 3dB will often put off the balance between fundamentals and overtones for male voices. With an 800 Hz crossover on the dome midrange, this isn't a function of the midrange driver, but the overall speaker voicing. Depending on the width of the baffle, most baffle step may not occur in the bass range at all- I'd suggest considering revisiting the system voicing via BSC adjustment.

My graph was made in room with a relatively long gate and shows the effects of room modes also. Additionally, this system doesn't use a "conventional" three way crossover; rather, it's an asymmetric target (4th order flat delay on LP, LP, with a basically 2nd order BP function for the midrange), looks like this:



At the design center frequency, 1500 Hz, all three drivers contribute to the output, and must track in the same relative phase; midrange is inverted.

Not many people have tried the HiVI; it's sort of expensive, even in the USA, though it is used in a popular line of speakers made by Totem Acoustic.

Agreed, copying or building other designs isn't that much fun, though occasionally instructive. I like looking at a lot of designs- you know, steal from the best, ignore the rest... :W

Let us know how your variant on the Zaph ZDT 3.5 turns out if you build it.



I've been asked to do an RS180-4 version of the system pictured above, it's still on my to do list, probably in late June at this rate. Trouble is, it will take more crossover components to deal aggressively with the RS180 breakup modes. I usually use as a test listening to the woofer circuit by itself, and if I hear any grunge, it's gotta get fixed. Even in a three way, I think the RS180 benefits from a trap.

[Jed]

Hello,

I plan to build a small 3way speaker.
I am now on driver selection:
Woofer: 1(2)x Seas L16RNX or 2x RS150


Any other comments are appreciated.

I already have Dayton RS52 midrange, but I find the sound a little thin.

Thanks

If you don't feel like learning how to measure you could build my upcoming Lineup Maxx L16 MK2. It uses the Seas L16RNX, TB W4 1337, and Seas 22TafG. More info is in the Maxx build thread in the MA section.

[minkuni]

One thing that makes doing a good "small" three way something of a challenge is the crossover network- assuming even just 2nd order networks, the crossover is about twice the size of that of a two way. That I haven't figured out how to get around or make smaller- which is why these are the smallest three way I've done. The crossover is split between four boars, attached to the rear part of the enclosure sides.

Maybe it would be easier if you chose more traditional ways of constructing the crossover? Or are you killing two birds with one stone (no extra enclosure stuffing)?



:B

[Dave Bullet]

I have used it with a 8" Beyma woofer Seas 27TDC tweeter (I had this drivers from another project). I have also tried Monacor DT-25T tweeter; nice visual match.
Crossover is LR2 at 800 and 4200Hz.

Response is flat, ~3dB BSC (this works well in my room).

How is the Beyma below 200Hz? Can you measure that low or are you splicing? If male voices sound thin, unlikely to be caused by the RS52 crossed at 800 Hz. Maybe the Beyma trades off midbass for efficiency (if a pro driver)? OR maybe you are used to hearing male voices with a little extra 2nd order distortion. Just some thoughts...

[JonMarsh]

Maybe it would be easier if you chose more traditional ways of constructing the crossover? Or are you killing two birds with one stone (no extra enclosure stuffing)?



:B

You've got it- high grade boar bristle and fur (preferrably wild- the farmed stuff just isn't the same)- the crossover is built on a section HDF laminated with the pelt.....
:rofl: :rofl: :rofl: :rofl: :rofl:

[augerpro]

If you don't feel like learning how to measure you could build my upcoming Lineup Maxx L16 MK2. It uses the Seas L16RNX, TB W4 1337, and Seas 22TafG. More info is in the Maxx build thread in the MA section.

Nice budget tweeter pick Jed. I look forward to hearing your impressions of it.

[Jed]

Nice budget tweeter pick Jed. I look forward to hearing your impressions of it.

Thanks Brandon. I should have went with it from the beginning considering its nice specs. I'm sure it'll sound very nice with the TB.

By the way I picked up a pair of Hivi D5.8 and TB W4 underhung drivers to play around with.