Best low pass inductor
One nice issue with the basic Manzi OB design is that it is very flexible. Not a design target, just how it works out. Basically anything from 15 Mh up to 24 Mh will work well with a couple of tweaks on the H.F. crossover. Less resistance and higher inductance value is a good target. You build the design and tweak with in your personal limits parts and cost wise. Use off the self stuff. So many ways around the barn. (OK, old Iowa framer talk, but you get the idea).
That is the beauty of it. For near zero dollars, and some time and effort you can obtain the sound balance you wish to achieve. Go for it!! You can not obtain a more simple, musical speaker for anywhere near the net cost. J
One nice issue with the basic Manzi OB design is that it is very flexible. Not a design target, just how it works out. Basically anything from 15 Mh up to 24 Mh will work well with a couple of tweaks on the H.F. crossover. Less resistance and higher inductance value is a good target. You build the design and tweak with in your personal limits parts and cost wise. Use off the self stuff. So many ways around the barn. (OK, old Iowa framer talk, but you get the idea).
That is the beauty of it. For near zero dollars, and some time and effort you can obtain the sound balance you wish to achieve. Go for it!! You can not obtain a more simple, musical speaker for anywhere near the net cost. J
Hi Pano and John
Any thoughts on adding a capacitor in front of the woofer to have an interaction between the capacitor and the coil of the woofer.
IT should give a boost for the deepest bas and Even out an eventual bump higher up.
And it would protect the woofer for real low frequencies.
Hobby Hifi a German diy magazine uses it a lot mostly in closed enclosures though.
Best regards
Uwe
Any thoughts on adding a capacitor in front of the woofer to have an interaction between the capacitor and the coil of the woofer.
IT should give a boost for the deepest bas and Even out an eventual bump higher up.
And it would protect the woofer for real low frequencies.
Hobby Hifi a German diy magazine uses it a lot mostly in closed enclosures though.
Best regards
Uwe
Heinz... yes you can add a big series cap. But it really will not give you much if anything in return. The GRS 15 operating Q with the current large inductor in series provides an on baffle QTS' well over 1.0. The area of the cone and 4.0 mm of Xmax will limit output capabilities below about 40 Hz. The woofer just doesn't have the displacement required to extend the bass any further down with usable output levels. And there is the added cost, efficiency losses and complexity with an added series cap. If one were using a very high Xmax 15" woofer, Say an Xmax of 10 mm or higher, then there maybe some advantage. But woofers with that kind of displacement are not inexpensive. You can of course acquire a large Xmax 15" and experiment. J
I just posted a complete set of components for this project circa 2017/early 2018 over at the swap meet.
Have fun.
https://www.diyaudio.com/forums/swap-meet/363898-fun-inexpensive-ob-project-includes-peerless-830669-a.html#post6434645
Have fun.
https://www.diyaudio.com/forums/swap-meet/363898-fun-inexpensive-ob-project-includes-peerless-830669-a.html#post6434645
Stands and tilt
I was lucky enough to jump on the deal Jerry posted.
This will be my first venture into.
Couple questions:
1) Are the non-Ultra version (ie. 15" wide x 27" tall) intended to be used on stands?
2) I was planning on using my set (once complete) with them placed on the ground. Maybe that would cause the mid/tweeter to be too low compared to the typical listening height. Thus, would it be okay to give the baffle a slight tilt (say 5 - 7 degrees)?
I was lucky enough to jump on the deal Jerry posted.
This will be my first venture into.
Couple questions:
1) Are the non-Ultra version (ie. 15" wide x 27" tall) intended to be used on stands?
2) I was planning on using my set (once complete) with them placed on the ground. Maybe that would cause the mid/tweeter to be too low compared to the typical listening height. Thus, would it be okay to give the baffle a slight tilt (say 5 - 7 degrees)?
No advantage to flush mounting the Peerless woofer, it has a surround made for surface mount. Flush mounting the Vifa won't hurt, but however you mount it, be sure the back can breath. If you just put it in a baffle tunnel the size of the cutout it won't be happy.
EDIT: For stand info see here:
Fast, fun, Inexpensive OB project
EDIT: For stand info see here:
Fast, fun, Inexpensive OB project
Hi Pano / John
Can I mount the 3" FR from behind in a 10 mm thick plate and then mill a 45 degree slope. Or will it work like a kind of horn so it will be too difficult to get the cross between the two drivers to work?
I am planning to make the baffle as a sandwich of 10 mm MDF, 4 mm bitumen, 18 mm MDF, 4 mm bitumen and 10 mm MDF.
12" will only be mountet to the 18 mm MDF in the middle, so hopefully less transmission to the front and rear of the baffle.
Middle and backside MDF will have a lager hole for the 3" FR
best regards
Uwe
PS with a baffle this thick do I need to make the wings more shallow?
Can I mount the 3" FR from behind in a 10 mm thick plate and then mill a 45 degree slope. Or will it work like a kind of horn so it will be too difficult to get the cross between the two drivers to work?
I am planning to make the baffle as a sandwich of 10 mm MDF, 4 mm bitumen, 18 mm MDF, 4 mm bitumen and 10 mm MDF.
12" will only be mountet to the 18 mm MDF in the middle, so hopefully less transmission to the front and rear of the baffle.
Middle and backside MDF will have a lager hole for the 3" FR
best regards
Uwe
PS with a baffle this thick do I need to make the wings more shallow?