diyAudio reference speaker project

Thanks for the info Rabbitz, good to see another novocastrian here.

I'll have a look at 6.5" drivers as well if the box does'nt need to be much bigger.

Thanks for the tip on the Seas tweeter. Is Aranmar the Aus distributor for Seas ?

Regarding design goals, I noticed that the response in WinISD using the drivers and dimensions specified in the Wiki (9.5L) was a not flat, thought I'd stuffed it up. I dug out your LDG I downloaded a while back and checked out vented box design. Looks like I've got a fair bit more reading to do about alignments etc

I'll move onto the crossover after the driver & box is sorted, so there'll be plenty more questions...
 
Yep.... Aramar are the guys for SEAS.
http://www.aranmaracoustics.com.au/

There's quite a few Newcastle guys around here.

When designing a box, you just need to tailor for the response curve and F3 you are after and most times that's not necessarily flat to suit tastes, baffle step or room loading. There are other factors of course such as xmax, power handling, group delay etc and it's about picking the right compromises. Not rocket science and mostly common sense.
 
Finally!

After such a long time I finally finished a "prototype" of these speakers.

In between I built a pair of Jay Kim's speakers using the SB woofer and little Vifa tweeter.

Anyway, I'm impressed with how this little speaker sounds. I used the singular because I've only built one so far. I have the one I just built on one channel and my Dynaudio Contour 1.1 on the other channel. Surprisingly they are a good match for the most part. Their frequency response isn't an exact match but close enough to play around with. I have the back clamped on for now but I'll glue it permanently later.

At first I only had part of the flared tube in the port and there was some harshness. After I added the rest of the tube it sounds great!

Thanks to all who contributed to the design, especially Rabbitz!
 
Thanks for your kind words. :blush:

Mine are still in use in my office and are the longest serving of my DIY speakers and are also still used as a reference point for new designs. I've changed the tweeter on mine to some Scan Speaks only because I had some left over from another design and is bit of an over kill for the design.... but hey, why not.
 
Heya rabbitz,

I have a pair of P13's and some XT25's kicking around that I picked up cheap.
Was thinking I might throw them together in your 'large' wiki reference box.........

Do you have any clues on a x-over for them ?
I was going to try the single 5uF cap but I dont think it will work with the XT25.....

Regards
:)
 
andrew01 said:
Heya rabbitz,

I have a pair of P13's and some XT25's kicking around that I picked up cheap.
Was thinking I might throw them together in your 'large' wiki reference box.........

Do you have any clues on a x-over for them ?
I was going to try the single 5uF cap but I dont think it will work with the XT25.....

Regards
:)

The 5uF cap will not work with the XT25 for sure as it does need a lot of help in a crossover.... more than I'm prepared to do. Last month I tried the XT25 in this speaker and was not a good match with too many nasties from the XT25 below the crossover point. It looked good by the modeling but didn't match up in reality. I didn't spend too much time on it by adding correction circuits and other fixes.

Dropped in a 27TFF, a redesigned crossover and some tweaks and it's a cracker.... a real smoothy and sweet. The XT25 went to ebay.
 
Moondog55 said:
I have made that same mistake, wanna swap the p-13s for a pair of P-11s, they cross over a bit higher 3.7/4k maybe easier to do.

Regards
Ted

When I first read that Ted I thought you wanted to swap some P13s for some P11s.... doh... <puts on glasses>.

The P13 with the 27TFF crosses over just above 3k and has an overlap of over 3 octaves. Allows both drivers to work well within their operating range. I was a bit worried and thought the 27TFF would need to be crossed over higher as it has a highish Fs (2 x XT25) but it handles the frequencies below the crossover point with ease and no nasties.

The XT25 just needs a lot of work and higher orders etc due to it's lower end behaviour. This will give you some idea of what's needed. Without this sort of effort it just doesn't want to roll off and believe me you don't want to hear below 1k on this tweeter.
http://www.troelsgravesen.dk/VifaPL14WJ+XT25TG.htm
http://www.zaphaudio.com/ZD5.html
 
I have enjoyed these speakers but feel that i am now ready to move "up a level"...in particular i think the bass needs some reinforcement.

I have had limited sucess with plate amp sub but would prefer to work on a proper three way to get acheive a more integrated solution

What drivers would you add to make these into a three way design?

or

would it be best to start over?

amongs my collection of drivers i have ss9500 tweeters and some Seas H571's.

I am limited to drivers available from Australia i guess? as i cannot find any retailers in NZ.... jaycar seem to only do PA or Car subs ;-)

My post jumps about a bit i suppose, what i am trying to acheive is my next project that delivers good results that i am happy to have invested in.... as a drummer i used to real instrument sound and dynamics, i would like to get a bit closer to this with my next project.

mark
 
diyAudio Member
Joined 2007
Perhaps you should read through this thread and then think about Ralphs solution, these drivers in a smallish sealed box and a good powered subwoofer

http://www.diyaudio.com/forums/showthread.php?s=&threadid=143326

Although I agree with you on Jaycars current line-up of woofers, you should be able to find something Have you tried Speakerbits.com??

http://www.speakerbits.com/net/catalogs/showpic1.aspx?id=PD315B
I haven't had a chance ( read money ) to buy a pair but the graph looks OK
And for a ported box perhaps these

http://www.speakerbits.com/net/catalogs/showpic1.aspx?id=VF250A

Sadly the M22 doesn't appear to be available any longer

Regards
Ted
 
D1GGY said:
I have enjoyed these speakers but feel that i am now ready to move "up a level"...in particular i think the bass needs some reinforcement.

You are right as they are limited in bass performance. Mine go down to 60Hz which is fine in the application but if more is required think of a 2.5 way but using a larger driver for the 0.5 woofer. Size of the 0.5 woofer depends on how much bass you want such as a P17 (to 40Hz) might be enough but a P21 (to 30hz) much more.

I've used this method with great success and actually forms the basis of my mains where a Vifa M22WR supplements the bass from an undersized sealed SS 18W8531. The 0.5 woofer only used a 1st order with an inductor only plus a oversized zobel for roll off shaping.

The other option is 2 woofer sections driven by plate amps and adjusted to suit. I tried this path but preferred the 0.5 woofer arrangement as it allowed the use of one amp and it's flavour to all the drivers. There's an example of this in the thread Moondog55 mentioned and is based on the Legend Big Red idea.

A 3-way is a very good but not an easy option unless you can find an existing design.
 
D1GGY said:
My post jumps about a bit i suppose, what i am trying to acheive is my next project that delivers good results that i am happy to have invested in.... as a drummer i used to real instrument sound and dynamics, i would like to get a bit closer to this with my next project.

mark
As a drummer, you might want to check out open baffles. They do an excellent job of reproducing drums and are DiY friendly.

Whatever type of speaker you decide on, however, I would look around for some of the many well-documented designs around the web. Designing multi-way systems is no joke and takes much study and practice to do well. It's better to study other people's designs for a while first before you embark on a design of your own.
 
andrew01

Cool. It's not a bad little device to have around and mine is still in use (uses the SEAS 27TFF tweeter these days). XT25 no less.... another variation on the theme.

Reading the link to the Okara speaker, that's the same problem I had using an AR xo with the XT25TG.
 
diyAudio Member
Joined 2007
What would be the reference point?

There are a number of good designs around for 3-ways but following on from the premise of the original 2-way build it would have to use readily available drivers, have a reasonable upfront cost ( which probably rules out SEAS and Scan-Speak drivers ) have a relatively simple XO and be reasonable easy to build the cabinet.

Given that here in OZ we are restricted in the cheaper woofers available to our US and EU members and that manufacturers are changing the production line up so rapidly that it is getting hard to stay current; which design and drivers would every one recommend.

New thread is now needed too.


regards
Moondog