2 way speaker - old school Vifa components. Should I bother

[svtcontour]

I had these parts purchased maybe 12 years ago and never used them. They just sat in their boxes because I was always so busy. I've got some time now and am wondering if I can get something put together that might be better than my Usher S-520 which I already like a lot. I have the same components as below, just made a while back...

Tweeters - Vifa D27TG45
https://www.madisound.com/store/product_info.php?products_id=1087

Woofer - Vifa P17WJ-00
https://www.madisound.com/store/product_info.php?products_id=1108


I was thinking of a floor standing speaker and I did find one or two references to that woofer being used in a transmission line setup which might be interesting. I'm basically looking for possible suggestions if its worth it.

 

[Swerd]

That woofer is a classic. There used to be many designs for it, mostly bass reflex bookshelf 2-ways, with a variety of tweeters.

After a quick look at them, I would guess that a 4th order crossover at 2 kHz would do well. Of course, the devil is in the details. I'll ask some people I know if they still have detailed designs for that combination.

You might get more results if you post this same question at the Parts Express Tech Talk forum. There are more experienced DIY builders there than anywhere else I know of.

 

[svtcontour]

Oh damn I didnt even know there was a parts-express forum. I knew you could buy from there but wow this is great. Awesome. Thanks man I will definitely be asking around over there. I really want to use these parts if possible

 

[TLS Guy]

I had these parts purchased maybe 12 years ago and never used them. They just sat in their boxes because I was always so busy. I've got some time now and am wondering if I can get something put together that might be better than my Usher S-520 which I already like a lot. I have the same components as below, just made a while back...

Tweeters - Vifa D27TG45
https://www.madisound.com/store/product_info.php?products_id=1087

Woofer - Vifa P17WJ-00
https://www.madisound.com/store/product_info.php?products_id=1108


I was thinking of a floor standing speaker and I did find one or two references to that woofer being used in a transmission line setup which might be interesting. I'm basically looking for possible suggestions if its worth it.

Both those drivers are great. If you want to build a tower you will need four woofers.

That combination will not need the complexity of a fourth order crossover.

I used that woofer in a bookshelf previously, unfortunately I have lost the circuit, but if I remember correctly it was first order low pass and second order high pass, but I'm not certain of that.

 

[Swerd]

Experts agree, both woofer & tweeter are worth keeping and using.

I spoke with a crossover designer friend, Dennis Murphy, who said:

I have one design using the Ellis 1801 cabinet (19 1/16" tall × 9 1/16" wide × 14¼" deep), and another in a Madisound 11 liter box, but I'm not sure I was crazy about either. Shamrock Audio (now defunct) used to have a design called the SE-1. But you had to pay for their schematics. I used to have a copy, but I have no idea where. Ron Lee would probably be willing to design a transmission line for him, and I could do a crossover if he wants to bother with all the shipping involved.​

To design a crossover, Dennis would need from you one cabinet (unfinished is fine), one woofer, and one tweeter. He lives in Bethesda, MD. When done, he will return your stuff along with a schematic diagram of a custom designed crossover.

Ron Lee said he would be happy to come up with a floorstanding TL-type design. He wants to know if the Vifa spec sheet that came with your woofers has the same Thiele/Small values that are now published by Madisound for that driver. Today's values may not be the same as those from 12 years ago.

Contact me by PM and I can give you their email addresses.

 

[svtcontour]

That is a great offer but I'm in Canada so I'd think shipping a cabinet will cost quite a bit. I did find a couple crossover designs that I think I will try and for the sake of simplicity, I'll try a large bookshelf first

You'd think that Vifa themselves could suggest something since its their products. I have not tried to contact them but I think I might and see where that takes me.

Experts agree, both woofer & tweeter are worth keeping and using.

I spoke with a crossover designer friend, Dennis Murphy, who said:

I have one design using the Ellis 1801 cabinet (19 1/16" tall × 9 1/16" wide × 14¼" deep), and another in a Madisound 11 liter box, but I'm not sure I was crazy about either. Shamrock Audio (now defunct) used to have a design called the SE-1. But you had to pay for their schematics. I used to have a copy, but I have no idea where. Ron Lee would probably be willing to design a transmission line for him, and I could do a crossover if he wants to bother with all the shipping involved.​

To design a crossover, Dennis would need from you one cabinet (unfinished is fine), one woofer, and one tweeter. He lives in Bethesda, MD. When done, he will return your stuff along with a schematic diagram of a custom designed crossover.

Ron Lee said he would be happy to come up with a floorstanding TL-type design. He wants to know if the Vifa spec sheet that came with your woofers has the same Thiele/Small values that are now published by Madisound for that driver. Today's values may not be the same as those from 12 years ago.

Contact me by PM and I can give you their email addresses.

 

[GranteedEV]

That is a great offer but I'm in Canada so I'd think shipping a cabinet will cost quite a bit. I did find a couple crossover designs that I think I will try and for the sake of simplicity, I'll try a large bookshelf first

You'd think that Vifa themselves could suggest something since its their products. I have not tried to contact them but I think I might and see where that takes me.

maybe not vifa, but i'd ask madisound. If the drivers are unchanged, they can do a sim in LEAP for a $30 charge.

 

[Swerd]

Here are the design details for a mass-loaded transmission line cabinet with one Vifa P17WJ woofer. This assumes the Thiele/Small parameters of your woofer are the same as those published by Madisound.

Predicted F3 is about 45 Hz, and at 2.83 volt (1 watt) input expected woofer excursion is less than 4 mm.

Cabinet:
Internal Dimensions
43" tall × 9" wide × 14½" deep

External Dimensions with ¾" thick MDF
44½" tall × 10½" wide × 16" deep

Center the woofer 11¼" below the internal top
Port 2" internal diameter × 9" long
Center the port on the rear baffle 6" above the internal bottom
At 2.83 volts input, the air speed through this port will be under 1% the speed of sound. No port noise.

Stuffing density 1 lb/ft³, 2.016 lbs total polyfill
Stuff the top 26.7" of the inside of the cabinet

Suggested Baffle Step Compensation circuit assuming 4 dB attenuation
BSC Inductor = 0.6 mH
Resistor = 2 Ω

Good luck with your crossover design.

Send me a PM with your email address and I'll forward you the results of the cabinet design including graphs of the predicted bass response.

 

[svtcontour]

Thanks Swerd I'll be looking into the specs for the older Vifa drivers. I've also toyed around with the idea of buying that woofer tester from Parts Express. I'll PM you my email address

svt.

Here are the design details for a mass-loaded transmission line cabinet with one Vifa P17WJ woofer. This assumes the Thiele/Small parameters of your woofer are the same as those published by Madisound.

Predicted F3 is about 45 Hz, and at 2.83 volt (1 watt) input expected woofer excursion is less than 4 mm.

Cabinet:
Internal Dimensions
43" tall × 9" wide × 14½" deep

External Dimensions with ¾" thick MDF
44½" tall × 10½" wide × 16" deep

Center the woofer 11¼" below the internal top
Port 2" internal diameter × 9" long
Center the port on the rear baffle 6" above the internal bottom
At 2.83 volts input, the air speed through this port will be under 1% the speed of sound. No port noise.

Stuffing density 1 lb/ft³, 2.016 lbs total polyfill
Stuff the top 26.7" of the inside of the cabinet

Suggested Baffle Step Compensation circuit assuming 4 dB attenuation
BSC Inductor = 0.6 mH
Resistor = 2 Ω

Good luck with your crossover design.

Send me a PM with your email address and I'll forward you the results of the cabinet design including graphs of the predicted bass response.