Driver selection question

[mneal]

Hi,
I'm a newbie working on a speaker project - front speakers for my HT system. My original thought was to do a MTMWW design similar to the ones in the Project Showcase. I thought I'd use 5" and 7" Dayton Reference drivers. I used Bassbox and X-Over to generate the design. Here's my question - would I end up with a nicer sounding speaker if I simplified the design and used higher end drivers? Or are the Dayton Reference drivers nice sounding, high quality units? Any advice will be appreciated.

[cjd]

The Dayton RS drivers are definitely top quality units - they test out there with some of the best stuff from Seas (the most direct comparison), Peerless, Scan... Superb components.

The problem is, the crossover is going to be the tough part. While it's not rocket science, understanding all the things that go into a good design can sure feel like it is. These drivers are a bit less forgiving (common trait for metal). NOT something I would personlly recommend to a newbie at speaker design.

I've done a study using the RS125 as mid and RS180 as woofer - pretty good stuff.

The Dayton RS drivers are definitely top quality units - they test out there with some of the best stuff from Seas (the most direct comparison), Peerless, Scan... Superb components.
The Dayton RS drivers are definitely top quality units - they test out there with some of the best stuff from Seas (the most direct comparison), Peerless, Scan... Superb components.

Take a wander over to HTGuide and check out the DIY Mission Possible section. Lots of designs there with Dayton RS drivers, from fairly small to huge. Roman B has a few excellent options, not to mention others I'm forgetting.

If you want to embark on learning crossover design, HTGuide may still be a good site - often threads go into more technical discussion on design issues, crossover variants/attempts, etc.

C

[killerkowalczyk]

Personally I would use the Dayton RS150 (6") for a mid over the RS125 (5"). The power handling in the RS125 is craptacular and distortion sets in very quick at semi loud volumes which greatly diminishes its imaging soon thereafter.

[Pete Schumacher ®]

> Hi,
> I'm a newbie working on a speaker project -
> front speakers for my HT system. My original
> thought was to do a MTMWW design similar to
> the ones in the Project Showcase. I thought
> I'd use 5" and 7" Dayton Reference
> drivers. I used Bassbox and X-Over to
> generate the design. Here's my question -
> would I end up with a nicer sounding speaker
> if I simplified the design and used higher
> end drivers? Or are the Dayton Reference
> drivers nice sounding, high quality units?
> Any advice will be appreciated.

You really ought to look at this design. It presents a far more forgiving impedance to the amplifier and offers a lot more bass performance.

The DA175 is an EXCELLENT driver, expecially for the price point, and if you use it within its intended range, provides great quality sound.

<A HREF="http://i12.photobucket.com/albums/a2...MWWproject.gif">http://i12.photobucket.com/albums/a2...MWWproject.gif</A>

<A HREF="http://i12.photobucket.com/albums/a2...iverlayout.gif">http://i12.photobucket.com/albums/a2...iverlayout.gif</A>

[Andy_G]

> Hi,
> I'm a newbie working on a speaker project -
> front speakers for my HT system. My original
> thought was to do a MTMWW design similar to
> the ones in the Project Showcase. I thought
> I'd use 5" and 7" Dayton Reference
> drivers. I used Bassbox and X-Over to
> generate the design. Here's my question -
> would I end up with a nicer sounding speaker
> if I simplified the design and used higher
> end drivers? Or are the Dayton Reference
> drivers nice sounding, high quality units?
> Any advice will be appreciated.

If I were you I would look for a project with the cross-over design given, rather than try to use X-Over-Pro to do a cross-over for something like the RS drivers.

[Chris Roemer]

> Hi,
> I'm a newbie working on a speaker project -
> front speakers for my HT system. My original
> thought was to do a MTMWW design similar to
> the ones in the Project Showcase. I thought
> I'd use 5" and 7" Dayton Reference
> drivers. I used Bassbox and X-Over to
> generate the design. Here's my question -
> would I end up with a nicer sounding speaker
> if I simplified the design and used higher
> end drivers? Or are the Dayton Reference
> drivers nice sounding, high quality units?
> Any advice will be appreciated.

I'd check your xo if you'd like, and your box, BUT you'll get the best value for your cash by finding a similar project and using it.

In the past 5 years I've probably built over 50 speakers, on paper, but I've only committed 1 or 2 a year to wood. Designing is almost as much fun as building, and it saves lots of $$$.

[mneal]

Here's my latest noobie brainstorm. What would y'all think if I use a pair of the RS 180 (4 ohm)for the bottom end, a pair of the RS 150 (4 ohm) for the mids and an Usher 9950 as my tweeter? I ran a simulation in X-Over Pro using crossover points at 500 and 2300, 2nd order APC filters for the LP and BP sections, and a 4th order APC on the HP filter. The response curve looked pretty flat to me. The only problem is that the impedance seems to hover around 5 ohms, and I'd like it closer to 8. Now I have a couple of questions:
1. Is there a way to increase overall impedance?
2. What do y'all think of the driver choices?
3. Are my crossover points and slopes reasonable, given the driver parameters?

Thank you very much for your help.

[Pete Schumacher ®]

> Here's my latest noobie brainstorm. What
> would y'all think if I use a pair of the RS
> 180 (4 ohm)for the bottom end, a pair of the
> RS 150 (4 ohm) for the mids and an Usher
> 9950 as my tweeter? I ran a simulation in
> X-Over Pro using crossover points at 500 and
> 2300, 2nd order APC filters for the LP and
> BP sections, and a 4th order APC on the HP
> filter. The response curve looked pretty
> flat to me. The only problem is that the
> impedance seems to hover around 5 ohms, and
> I'd like it closer to 8. Now I have a couple
> of questions:
> 1. Is there a way to increase overall
> impedance?
> 2. What do y'all think of the driver
> choices?
> 3. Are my crossover points and slopes
> reasonable, given the driver parameters?

> Thank you very much for your help.

The only thing I'd change would be to use Dual 8 inch woofers, RS225. The crossover points are very reasonable.

Did you factor in baffle diffraction when you modeled the crossover? Or did you just use the manufacturers plots? if you didn't factor in the baffle response, it's likely that if you went with Dual RS225-4 and a single RS150-8 with the Usher would give you a flatter response and a more benign impedance.

[curt_c]

I'd like to see the Xo network, and impedance plot. If you have the 4 ohm drivers in series, you should get much closer to 8 ohms.

C

[johnastockman]

Provided Link: FRD Tools


> Hi,
> I'm a newbie working on a speaker project -
> front speakers for my HT system. My original
> thought was to do a MTMWW design similar to
> the ones in the Project Showcase. I thought
> I'd use 5" and 7" Dayton Reference
> drivers. I used Bassbox and X-Over to
> generate the design. Here's my question -
> would I end up with a nicer sounding speaker
> if I simplified the design and used higher
> end drivers? Or are the Dayton Reference
> drivers nice sounding, high quality units?
> Any advice will be appreciated.

Welcome! For a better XO program go to the link and download Jeff B.'s excellent PCD, for free. It uses actual measurement files (*.frd and *.zma) and Roman B. has a great tutorial for the FRD tools. The thing with XO Pro is it only uses the driver parameters, not measured responses. As the other gents suggested, one of the proven, tested projects using the RS drivers or the DA175's like Pete mentioned would certainly give you a fantastic result. You can use PCD and the available files to model your chosen drivers, also.

Roman's site: <A HREF="http://www.rjbaudio.com/">http://www.rjbaudio.com/</A>

Good luck!

John A.