Looking for Full Range for mid in Open Baffle

Hi,

I have got my prototype 3 way up and running, with the Supravox running full range.

Excellent.

I have had to pad the Supravox down with a 1.7 Ohm resistor to match the bass and treble.

As alternative, you can try without resistor and reduce the fieldcoil voltage.

I have (for the moment) continued with the Seas tweeter, as I really like it's sound. However to get it to integrate, I have had to bring it in above 10K. Anything below this damages the midrange coherence.

Yes, that pretty much matches my experiences using the Visaton TL-16H horn tweeter. I think my X-over was a little higher, but not a lot and 1st order.

Thanks for your help.

No worries. Post some pictures though, will be interesting for the others.

Ciao T
 
As alternative, you can try without resistor and reduce the fieldcoil voltage.

Yes, I need to do some further experimentation!

Also, because I have a small baffle on top of a sealed box, I have a broad notch filter centred around 500Hz on the Supravox. Unfortunately, I cannot see a way around this.

Yes, that pretty much matches my experiences using the Visaton TL-16H horn tweeter. I think my X-over was a little higher, but not a lot and 1st order.

I have 2.64uf on the Seas which has a Z (also Re of 6 @ 10K) of 6 Ohms. My calculator says that is 10KHz. I have tried slightly lower, and it just falls apart. I may end up going slightly higher - I need to get some finer grade films.

No worries. Post some pictures though, will be interesting for the others.

Will do, but this thing is very ugly!

I am just using a cheap little Denon mini system to drive this at the moment, and this speaker is blowing my mind - It is positively funky!!!!

Cheers

David
 
Hi David

quote:
The open baffle acoustically rolls it off from 250 Hz at 6 db/octave

. . that is measured?

I'm thinking of using that driver on an OB, but need to get it flat down to 160 Hz (the flat limit of my intended subs) - or I may need to use a bigger Supravox . . .

How wide is your baffle; and as voltage affects the Qes and Qts, with what voltage are you running the Supravox?

Cheers

Richard
(you may know me as the MAC Editor ;) )
 
Hi David,
I use the Supravox 215-ESC field drivers in open baffle with excellent results:cool:.
They are currently run at 7.0 volts and full range with Fountek ribbon supertweeter crossed over at 10Khz first order. The bass (70 Hz and below) come from a separate active crossover and power four open baffle 15" Hawthorne Augie woofers. The bass is equalized with a DEQ 2496. Attached is a picture.

Have fun with your speakers,
Jim Levinson
 

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Hi Otto :))),

Hi David

quote:
The open baffle acoustically rolls it off from 250 Hz at 6 db/octave

. . that is measured?

Yes.

I'm thinking of using that driver on an OB, but need to get it flat down to 160 Hz (the flat limit of my intended subs) - or I may need to use a bigger Supravox . . .

A bigger driver will not help, this is just the cancellation due to the open baffle and is determined by the baffle size.

How wide is your baffle; and as voltage affects the Qes and Qts, with what voltage are you running the Supravox?

My baffles are 34cm wide at their widest (they are hexagonally shaped), but are fairly thick. I will probably make the final version thinner, but with a maximum width of about 38cm.

I am running mine at 6.0V at the moment with no resistor pad.

If you want to get down to 160Hz, you are going to need fairly large baffles. Have you dowloaded any simulation programs such as Tolvan Edge?

Also, these guys need a helper tweeter to get a realistic treble response.

Cheers

Richard
(you may know me as the MAC Editor ;) )

Ah yes, the busy one - you missed a great night on Wednesday, best sound I have heard in the Willis room.

Cheers

David
 
Hi David,
I use the Supravox 215-ESC field drivers in open baffle with excellent results:cool:.
They are currently run at 7.0 volts and full range with Fountek ribbon supertweeter crossed over at 10Khz first order. The bass (70 Hz and below) come from a separate active crossover and power four open baffle 15" Hawthorne Augie woofers. The bass is equalized with a DEQ 2496. Attached is a picture.

Have fun with your speakers,
Jim Levinson

Hi Jim,

Glad you are enjoying your speakers!!

I am really impressed with the Supravox driver. I was originally goin to use it as a midrange driver, but once I heard it full range my plans changed :D.

I am running mine at 6V to match with the efficiency of the bass and treble, and have an LRC trap to suck out the open baffle 500Hz boost.

The tweeter is now running (first order) with an f3 of 18K.

Best Regards

David
 
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Joined 2012
Paid Member
Hi, I am looking for a full range driver to use as a midrange in a 3 way open baffle. All the best - most lifelike and dynamic - drivers I have heard have been full ranges like Lowther, Coral, Fostex, etc.

Can anyone suggest a driver that would make a great mid range ( 250 - 2k+) without having to cut of wizzer cones etc?

What are the Supravox and PHY drivers like (never seen or heard these)?

I bought Seas Exotic W8's, hoping that they would do what I want, but so far I am disappointed - they sound quite flat :(. I will continue to run them in, but I suspect that I need to find an alternative. Thanks David

For a midrange, maybe try The 12" Alnico Tone Tubby

or this one https://www.madisoundspeakerstore.c...fostex-f120a-5-full-range-with-alnico-magnet/

or these very intriguing ESL mini panels
Mini Panels

Of course, any disparate driver sensitivities will likely be an issue. That what's driving me absolutely insane with the OBs I'm planning, especially if you're trying to avoid bi-amping.
 
I love OB and have been experimenting with different drivers on top of H-frames for over a year. The sound is much more lifelike and the imaging is wider, filling the room with more music. I'm happy to see others enjoying OB.

In my experience, baffles must be wider than 17 inches to comfortably connect to the bass. Some drivers are better than others and price often means nothing.

It is nice to see TL on the forum again.
 
Member
Joined 2012
Paid Member
In my experience, baffles must be wider than 17 inches to comfortably connect to the bass. Some drivers are better than others and price often means nothing.

These OBs are 18" wide Tiny Alnico Open Baffle
and use the 12" Tone Tubby Alnico The 12" Alnico Tone Tubby
Would you choose the TT in this size OB, or this one
http://www.greatplainsaudio.com/downloads/416-8B Spec Sheet.pdf ?

Or would the GPA 416s be too big for this OB?

Do you find that you usually need to bi-amp to achieve full satisfaction?
 
I did buy and I would recommend the SEAS Exotic W8 for open baffle use. They are what I would describe as a very modern sounding driver compared to say Alnico vintage drivers like Sabas and early Supravox. The sound is clear and crisp with good resolution between instruments.
 
I did buy and I would recommend the SEAS Exotic W8 for open baffle use. They are what I would describe as a very modern sounding driver compared to say Alnico vintage drivers like Sabas and early Supravox. The sound is clear and crisp with good resolution between instruments.

what filter settings would you recommend? did you use it with tweeter and subwoofer?