SEAS A26 in oversize cabinet

[nugat]

I ordered the SEAS A26 kit (mid woofer and tweeter) and am about to build the cabinet (aperiodic) which is specified at 28 l. volume.
I'm mostly after the above 80Hz spectrum as the bottom two octaves are taken care of by my distributed bass system.
I've been thinking of increasing the cabinet volume but mostly for the soundstage enlargement sake, not bass.
I will appreciate any thoughts, opinions, advice on this idea.
Real life experience cases also appreciated.

 

[sreten]

Hi,

I'd stick to the specified design. Not much to be gained here.

However you could turn it into sealed and stuffed floorstander,
just by extending the specified box downwards, should be fine.

Adding some bracing would be a good idea.

rgds, sreten.

 

[system7]

Here is an established variant in a bigger closed box. Must be 50-60L or maybe more. The Vas/Qts calculation gives you a whopping 85L.

Designing Loudspeakers - WD25T EX - The next step

http://www.diyaudio.com/forums/multi-way/272810-devore-orangutan-clone-4.html#post4686977

 

[system7]

Peter Comeau did a bit more than I thought there. It is about 60L, but he has placed an aperiodic vent half way down the closed cabinet.

He must know what he is doing.
http://user.faktiskt.se/M_N/WD25T_Part1.pdf

Reduces the stuffing required, and it works as bracing too.

 

[irext]

Hi Steve. Thanks for the link to the WD25T EX. I am quite interested in this build as I am quite a fan of the Devore Orangutan which I heard at a HI FI show a year or so ago. I thought it was the "best in show" at the time and was very impressed with its ability to make any recording come alive. I've been looking at the Seas A26 kit but I like the idea of a slightly taller larger enclosure. The second link you gave didn't work for me (said I didn't have access) I assume it had the cabinet details. Do you have the cabinet details in another format.

Cheers : Ian T.

 

[planet10]

Scott & i did this revistion of a classic TL for these drivers.

http://p10hifi.net/tlinespeakers/FAL/box-plans/classicTL-revisited-WD.pdf

dave

 

[nugat]

I am interested in using the new A26 kit with the new T35C002 tweeter (and A26RE4 paper mid- woofer). In the 28L box Seas designers propose to cross them at 1500hz with a simple
high pass filter (1 cap, 1 resistor). The midwoofer works full range.
I really like the simple crossover idea and would like to preserve it in a bigger cabinet.
My goal is to have the speaker work nicely with my distributed bass system (4 subwoofers)
and take over from ca 60-70 hz.
The thing I'm really after is bigger soundstage than in the 28L box.
Do you think I can simply enlarge the cabinet to 60-70 litres and keep the original A26 drivers/XO setup? The only parameters to regulate would be the resistor value and stuffing
(or lack) of the aperiodic slot.

 

[system7]

Of course, nobody knows what crossover is in the Orangutan. But a 10" bass and a low crossover tweeter just play nicely together.

Peter Comeau does a more sophisticated filter than SEAS, and a better sounding one from my experiments. I think it is marginally changed by the bigger baffle, perhaps on the crossover null particularly, but hardly audible I'd think. Varios Excel SEAS tweeters were used over the years, people have even used metal ones.

Here's the build pdf for the WD25T EX. I don't have the tuning up Part 2. Planet 10's transmission line must be good too. People always make out transmission lines are hard, but they all look the same to me.

 

[sreten]

Hi, IMO speaker volume has little to do with soundstage size, rgds, sreten.

Especially in the case of subwoofers and satellites.

 

[adejacko]

Never heard the WD25t, but I bet they sound great. Am looking for a speaker to build that I can place near walls. Peter's design was for just that and am strongly considering it (with a pair of the cheaper tweeters) Out of interest anyone know of any other similar designs?

 

[planet10]

As long as the box is well damped (low Q) it can be placed against the wall.

Say 220 litres with heavy volume fill damping if you can manage that large. Otherwise you need a driver with lower size box requirements.

dave

 

[fatmarley]

I am interested in using the new A26 kit with the new T35C002 tweeter (and A26RE4 paper mid- woofer). In the 28L box Seas designers propose to cross them at 1500hz with a simple
high pass filter (1 cap, 1 resistor). The midwoofer works full range.
I really like the simple crossover idea and would like to preserve it in a bigger cabinet.
My goal is to have the speaker work nicely with my distributed bass system (4 subwoofers)
and take over from ca 60-70 hz.
The thing I'm really after is bigger soundstage than in the 28L box.
Do you think I can simply enlarge the cabinet to 60-70 litres and keep the original A26 drivers/XO setup? The only parameters to regulate would be the resistor value and stuffing
(or lack) of the aperiodic slot.

If you're using subs I'd just stick to 28ltr. Going bigger just trades midbass for more low frequency extension.

EDIT: Just realised I replied to a 5 year old post.

 

[Julesottawa]

Here is an established variant in a bigger closed box. Must be 50-60L or maybe more. The Vas/Qts calculation gives you a whopping 85L.

Designing Loudspeakers - WD25T EX - The next step

http://www.diyaudio.com/forums/multi-way/272810-devore-orangutan-clone-4.html#post4686977

Any problem doing this speaker with the T35 tweeter from SEAS? Plan B would be a horn tweeter for fun!

 

[planet10]

28 litres is an undersized box made aperiodic to help remove the bump at the bottom. About 60-70 litres is right-sized. It will give a smoother roll-of and make for a flatter response for the XO to look into.

This much newer thread has current thots on A26 cabinets:
https://www.diyaudio.com/community/threads/seas-a26-devore-style-build.369124/
dave

 

[Julesottawa]

Thank you. I will follow that thread too.
I'm thinking of sizing my next cabinet to the JBL L100 classic with aperiodic loading.

 

[hammerz]

I've just started my project «SEAS A26 floor stander». Pretty much like the SEAS recommendation, but the height is extended to 85cm. 18mm BB plywood with bracings.

Considering making the rear wall removable with sealing and screws. It would be easier to experiment with damping material. In addition, I can go for M5 machine screws for attaching the woofer. Any views on this?