Minimus 7 woofer + TB w3-871S

[fireman]

A while ago, I asked advice on how to repair a damaged Minimus-7 tweeter. I got quite a few interesting answers but eventually, I had to admit that both tweeters are way past their prime.

Last week, I then ordered 6 TB W3-871S so that I can play with different designs. That got me thinking about something. How about building a small 2 way speaker with a 871 and a Minimus 7 woofer ? The problem is, I have no specs for the woofer.

Is there a chance that somewhere, someone has the technical data for those little woofers ? I thought I might use the Minimus internal volume as a start point. Would I be better of putting the 871 in it's own sealed box or could they share the same volume ?

What do you guys think ? Is this a good idea ?

[Cal Weldon]

Bonsoir Jean-Pierre,
Comment ca va?

OK that's my only Francais

My thought is that if you are putting the effort into building a small 2 way set up then why not gather your pennies and update the woofs.

I remember the Minimus 7 well. I was young and awestruck, darn near in love with my first set. Things are different now. Maybe go talk to your local DIY shop and see what they have to go with your tweeters and Xovers. Or keep the 7's together and start anew. No need to mess with a great little, underated, classic speaker.

I hope that didn't hurt

From the left coast
(a votre) sante!
Cal

[AldebaranTech]

Miniumus 7 woofer parameters as measured with Speakerworkshop:
Fs 64Hz
Vas 3.27L
Qts 0.361
Qms 2.330
Qes 0.428
Le 0.8mH
Re 6.4 ohm
Sd**2 53.5 sq cm


other parameters not determined, sorry, but this should get you started.

The M7 box volume is close to 1.5L taking into account the space taken up by the drivers.

The M7 system starts rolling off at about 240Hz and using 1KHz as the reference level, the -3 db point is around 200Hz. The system's mid to treble response is actually pretty horrible. It drops to -4db at around 3KHz and rises steadily to +6db at 10KHz and then drops again at the same rate/curve to -3db by 20KHz.

WinISD shows a possible improvement to the lower end response by adding a port or ports to turn the box into a bas reflex with the port/s tuned to close to 70Hz.

Any improvement to the overall sound of these speakers will require new tweeters as you are suggesting you might do, and/or much work in the crossover department. This might be an interesting experiment, but only for academic reasons, there can be no practicle benefit.

The Tagband 4" fullrange driver could probably perform better in a suitable box by itself rather than try and redesign these things, but I could be wrong. I might play with them myself

[fireman]

Originally posted by Cal Weldon
Bonsoir Jean-Pierre,
Comment ca va?

OK that's my only Francais

My thought is that if you are putting the effort into building a small 2 way set up then why not gather your pennies and update the woofs.

I remember the Minimus 7 well. I was young and awestruck, darn near in love with my first set. Things are different now. Maybe go talk to your local DIY shop and see what they have to go with your tweeters and Xovers. Or keep the 7's together and start anew. No need to mess with a great little, underated, classic speaker.

I hope that didn't hurt

From the left coast
(a votre) sante!
Cal

Hi Cal,

your french might be a little limited but it's quite good. You're right in putting the effort in finding a suitable woofer for a 2 way. I guess I'll experiment first with the 871 to see exactly how they sound and how the size of the enclosure and different XO affect them.

Whan I'm more experienced, I'll take a look around to try to find a suitable woofer for a two way. Who knows, maybe someone will already have tried something interesting to work with.

As far as a local DIY shop is concerned, unless you are talking about Radio-Shack, the closest one is an hour and a half away (Québec City). They carry almost exclusively car audio stuff. There's also Solen that carries a lot of high-end drivers and parts. For now, this option is too expensive for me. Right now, I could probably say that Nuera as well as CSS. They offer affordable drivers and this really important for me as I am still grasping to learn the basics.

Originally posted by AldebaranTech
Miniumus 7 woofer parameters as measured with Speakerworkshop:
Fs 64Hz
Vas 3.27L
Qts 0.361
Qms 2.330
Qes 0.428
Le 0.8mH
Re 6.4 ohm
Sd**2 53.5 sq cm


other parameters not determined, sorry, but this should get you started.

...

Any improvement to the overall sound of these speakers will require new tweeters as you are suggesting you might do, and/or much work in the crossover department. This might be an interesting experiment, but only for academic reasons, there can be no practicle benefit.

The Tagband 4" fullrange driver could probably perform better in a suitable box by itself rather than try and redesign these things, but I could be wrong. I might play with them myself

Hello AldebaranTech,

Thanks for the info. Unfortunately, after reading both previous posts, I think I'm better off selling the Minimus-7 and using the money to buy an appropriate woofer that would match nicely with a TB 871.

As I said earlier, I'll play with my 6 TB 871 for a while and when I feel comfortable with the technical stuff, I'll try searching for a nice little woofer.

[Lionel]

Originally posted by fireman


Right now, I could probably say that Nuera as well as CSS. They offer affordable drivers and this really important for me as I am still grasping to learn the basics.

Bonjour,

With all your posts concerning the TB 871s you have awaken my curiosity.
But the TB speakers are very expensive in Europe.
May I ask you where have you purchased yours, and which way of payment you have used ?
I'm not very comfortable with intercontinental purchases...
Thank you for your help,
Lionel

[Dark Shadow]

Originally posted by Lionel


Bonjour,

With all your posts concerning the TB 871s you have awaken my curiosity.
But the TB speakers are very expensive in Europe.
May I ask you where have you purchased yours, and which way of payment you have used ?
I'm not very comfortable with intercontinental purchases...
Thank you for your help,
Lionel

Like Jean-Pierre said, Nuera Acoustic and Creative Sound sell it online. Nuera accept paypal paiement and I asked them a quote to order some TB W3-871S (12.00$US Each) and a TB W8-740C (32.50$US Each).

[fireman]

Originally posted by Lionel

Bonjour,

With all your posts concerning the TB 871s you have awaken my curiosity.
But the TB speakers are very expensive in Europe.
May I ask you where have you purchased yours, and which way of payment you have used ?
I'm not very comfortable with intercontinental purchases...
Thank you for your help,
Lionel

Bonjour Lionel,

je suis bien content de rencontrer un autre utilisateur francophone. Tu peux m'écrire en privé si tu désires poursuivre la discussion en français. Back to Shakspeare mother tongue. When I ordered my 6 TB W3-871S from Nuera, they were listed at 10.00 $ USD. They cost me 13.00 $ CDN plus 13.50 $ CDN for shipping and 5.87 $ CDN for GST (sales tax) for a grand total of 103.22 $ CDN. CSS quotes them at 15.50 $ CDN and 5.00 $ CDN each for shipping. You've got to add 7% sales tax on top of that for a grand total of 126.26 $ CDN.

Billy of Nuera was quick to respond to my inquiry. He ship my drivers the days after receiving the money through Paypal. In all honesty, I have to admit I didn't contact the folks at CSS. I got all the information I needed from their web site. I don't want this thread to sound like I got lousy service from CSS. That just is just not true. I went for the lowest price. That's all.

Originally posted by Dark Shadow

Like Jean-Pierre said, Nuera Acoustic and Creative Sound sell it online. Nuera accept paypal paiement and I asked them a quote to order some TB W3-871S (12.00$US Each) and a TB W8-740C (32.50$US Each).

Nuera offers a volume discount. Right now, if you buy 5 TB W3-871S or less, the price is 12.00 $ USD. If you intend to buy 6 or more, they will cost you 10.00 $ USD.

[Lionel]

Merci pour ta sympathique proposition, et je ne m'en priverai pas si le niveau dépasse mes compétences.

I'm new on this forum and I have been astonished by the comments concerning this little speaker (TB 871s).
I have 2 old Cabasse 30BZ18 (1979 - 30cm) which are in perfect shapes but still unemployed.
They aren't really deep "boom boom" boomers but as they are gently "musical" up to 900 hz, I guess they could be good partners for the TB 871s.

My idea is to have 4 TB 871s + 1 Cabasse 30 BZ18 per speaker.

Now I'm trying to imagine a cabinet design who will be able to reach my drastic WAF specifications.