Philips 9710 M/8 new enclosure help.

[Xerxes75]

I have pair of 9710’s and they play beautiful in a TQWT enclosure. I am building a second large open baffle system and four big units is a bit much. So I thought building a second but smaller home for my 9710’s.

I am not a expert and there is so much written about these speakers that I get a bit confused.

Now I found a perfect looking speaker and I wish to build something like that. It is the Hoyt Bedford 1.5 tower, this is a BR enclosure with the following size

H27”68.6cm W11.5”/29.2cm D 11”/27.9cm as said I like the look and dimensions but I have no idea if this would work. I don’t have the knowledge or software etc.

I am open for suggetions, maybe changing the dimensions a bit, I even thought about a mltl with the opening on the under side (no idea if that would work but in my head it looked nice…)

[DrBoar]

The 9710 has a 10 db step at about 2 kHz so it sounds very shouty if facing forward. Angled up and backward (Decca corner horn) it sound really good.

It can be made to work facing forward but then you need some eq network
Philips 9710/

But if you want it as a full range driver with no eq it has to face upwards like the Ace horn or backwards as the Decca.

[IG81]

In a ~50L reflex tuned to 39Hz, my pair did OK, but no much more. It's on the small side and bass was starting to be boomier than I like, a matter of taste I suppose. Might have been more acceptable in a larger room than mine too. They do have that shout as Dr.Boar mentions, both subjectively and what I measured, but listening relatively off-axis helped matters. In any case, it's hard to go small with 9710.

Here's a small compendium of 9710 applications:

Applications Philips 9710 m

[Squeak]

With a Qts of 0.55 and a Fs of 45 the 9710 wants a large cab. Maybe you could do an OB but they don't really take up less space and would bro ably need a sub.

The rising highs are a plus not a bad thing. They do need to be "dealt" with though.
Use a foam lens to disperse the highs and avoid so much beaming.
Or aim the driver up and use a convex reflector above it.

[Xerxes75]

Thanks for your comments and ideas. Mmmmhhh mabye not all what I wanted to hear but now I know for sure that small is difficult.
The proposed enclosures are very good I think but to big. Although the beaming up thing seems interesting. I had seen this design but I wasn't sure that it could sound good

The highs on the 9710 are a plus to me....I love the sound! But I whil try to listen it with the proper filter/correction....and mabye than it sounds even better.

I had a very bad copy of the paper mentioned in the link...thanks! Now I can really read it.

I have to think it over but mabye I can place a sub(s), I have two Philips ad12100 W/8 lying around... Or make use of the bass in the new to build OB...

Well options options options...thanks so far!

[DrBoar]

Those AD12100 W/8 are relly good woofers with good TS parameters.

[esgigt]

Due to ageing and material deterioration, the TS parameters on the internet are unreliable for old speaker-units. For a successful project you ought to make individual measurements.

[IG81]

Originally Posted by esgigt

Due to ageing and material deterioration, the TS parameters on the internet are unreliable for old speaker-units. For a successful project you ought to make individual measurements.

I think the commonly seen set of parameters for 9710 is pretty reliable for drivers in good condition. My pair measured very close to the data published by Troels Gravesens; heck, I've had new drivers differ from factory specs by a lot more. I think DrBoar's data is that same group as well. Not that I don't agree it's ultimately best to measure yourself.

[esgigt]

Originally Posted by IG81

I think the commonly seen set of parameters for 9710 is pretty reliable for drivers in good condition. My pair measured very close to the data published by Troels Gravesens; heck, I've had new drivers differ from factory specs by a lot more. I think DrBoar's data is that same group as well. Not that I don't agree it's ultimately best to measure yourself.

You might have been lucky with your 9710's... on the other hand it ofcourse is also possible that the ageing of the 9710's is within a certain (reliable) bandwidth.. but you had to measure to be sure.

[Xerxes75]

I don't have measurement equipment so that's solved. The 9710 and the 12100 are as good as new. This morning I did some reading about up firing speakers and more in detail the Sonab 5, it looks simple to make but those tweeters are very hard to get I read.