Bozak 302 Urban question

[Plimpington2]

I have a line on a pair of 302’s Urban. They are clearly mismatched as stickers and serial numbers on the back are vastly different. They are:

A25086 (model B302A Urban)
B46769 (model B300 Urban)

I assume these are the same speaker. They certainly look the same. But I have not been inside.

Wondering whether one or both of these are likely to have the aluminum tweeters and midrange.

 

[Rapscallion]

I have the 302a. Has the aluminum mids and tweets. 300 might be the two way version, but could have been upgraded.

Not many screws holding on the covers so it’s easy to check.

 

[SiliconTi]

The were kits to modify the 300 to a 302. I agree, pull the front grills off and take a gander. Maybe you'll get lucky. My advice, if they're in good shape and sound great, do not modify them.

 

[Rapscallion]

The were kits to modify the 300 to a 302. I agree, pull the front grills off and take a gander. Maybe you'll get lucky. My advice, if they're in good shape and sound great, do not modify them.

Agreed. I updated the crossovers, which was a fairly brisk undertaking compared to most speakers. But left them alone otherwise.

 

[drbiggles]

Bozaks are one of the few manufacturers where owners are applauded for modding, updating, whatever. For systems where the tweeters are mounted over the woofer, stock tweeter attenuation is 9 db. This makes them quite dark for most low to medium levels. A later factory wiring schematic the mids were wired out of phase, this makes the mids way too dang bright. A stock crossover point was to have the woofer and mid meet at 800hz. This pushes the B199 woofer past its useful frequency range, 400 and even 200 is a remarkable difference. Stock crossover points bring the mid to 2500hz to meet the tweeters. The B209B mid has impedance spikes that make them too bright, even shrill under a fair amount of juice. Using Pat Tobins suggestion of 1250hz has the mid and tweeters slide into each other with grace and clarity. Modding, updating modernizes Bozaks to give you a remarkable, even handed and balanced loudspeaker system. But you’re free to do what you wish, they belong to you.

Biggles

 

[Plimpington2]

Bozaks are one of the few manufacturers where owners are applauded for modding, updating, whatever. For systems where the tweeters are mounted over the woofer, stock tweeter attenuation is 9 db. This makes them quite dark for most low to medium levels. A later factory wiring schematic the mids were wired out of phase, this makes the mids way too dang bright. A stock crossover point was to have the woofer and mid meet at 800hz. This pushes the B199 woofer past its useful frequency range, 400 and even 200 is a remarkable difference. Stock crossover points bring the mid to 2500hz to meet the tweeters. The B209B mid has impedance spikes that make them too bright, even shrill under a fair amount of juice. Using Pat Tobins suggestion of 1250hz has the mid and tweeters slide into each other with grace and clarity. Modding, updating modernizes Bozaks to give you a remarkable, even handed and balanced loudspeaker system. But you’re free to do what you wish, they belong to you.

Biggles

Well, to be perfectly honest I believe having the tweeters mounted over the woofer, which sits just about 12 inches off the floor, is what really hurts these. I don’t like the sound to come from so low.

So . . . I like these because they have a super great mid century modern look, which will go well with my mid century modern credenza. What I intend to do with these (and now it gets heretical) is replace the baffles with a new one that can accommodate a Stephens Ultrasonic 15” dual concentrics (or maybe even Tannoys, if i can afford). Rehab the cabs and grills and be happy. These will be a project. I think these are some of the best looking vintage speakers around!

 

[drbiggles]

Well, to be perfectly honest I believe having the tweeters mounted over the woofer, which sits just about 12 inches off the floor, is what really hurts these. I don’t like the sound to come from so low.

So . . . I like these because they have a super great mid century modern look, which will go well with my mid century modern credenza. What I intend to do with these (and now it gets heretical) is replace the baffles with a new one that can accommodate a Stephens Ultrasonic 15” dual concentrics (or maybe even Tannoys, if i can afford). Rehab the cabs and grills and be happy. These will be a project. I think these are some of the best looking vintage speakers around!

Heretical schmertical, do what you please. The cabinets are too small for those drivers, barely 5 cubic feet. They're probably under, I'd measure. You'd want 12" drivers for the 302 cabinets. And they're not ported, that will have to be engineered. Honestly, they're going to need to be braced. IAM working, very slowly, that's not only braced, but lined with 3/4" ply. Gonna weigh a freaking ton. I'll lose a little lower bass, but it'll improve my midbass slam. Drums will slam into your chest with authority, make you giggle like a young school girl. B199 woofer, B209B, some modern tweeter mounted in small a cabinet that rests on the top. My monoblocks do 40 watts. At near full volume they'll take your breath away.

Biggles

 

[Plimpington2]

Heretical schmertical, do what you please. The cabinets are too small for those drivers, barely 5 cubic feet. They're probably under, I'd measure. You'd want 12" drivers for the 302 cabinets. And they're not ported, that will have to be engineered. Honestly, they're going to need to be braced. IAM working, very slowly, that's not only braced, but lined with 3/4" ply. Gonna weigh a freaking ton. I'll lose a little lower bass, but it'll improve my midbass slam. Drums will slam into your chest with authority, make you giggle like a young school girl. B199 woofer, B209B, some modern tweeter mounted in small a cabinet that rests on the top. My monoblocks do 40 watts. At near full volume they'll take your breath away.

Biggles

I hear what you’re saying about the size. Here’s the thing, though. The Tannoy Ardens are (not including the footers) 34 x 24 x 14 = 11,424. The 302’s are 24 x 24 x 20 = 11,500. I think they ARE big enough to accommodate a pair of 15’s. I agree - new baffle would have ports. And the cabinet will need bracing. But I believe the bones are good.

 

[drbiggles]

They’re a great foundation! I still disagree. Are your measurements from interior or exterior? Iam assuming interior. With your numbers the Ardens are exactly 8 cubic feet, they’re perfect for all vintage 15” drivers. Your measurements for the 302’s come to 5.5 cubic feet. While perfect for vintage 12” woofers, this will noticeably choke your lower octaves. Porting will help. But you’ll find the difference between the two cabinets will be remarkable. If you do any bracing at all, your bottom end will suffer more. You should rework a pair of Bozak Symphonies, those are a tad under 8 cubic feet.

Biggles

 

[cwh]

Urban B300 owner here. Mine came loaded with JBL D130s which got traded for a full 302 load of B199, B209, B200y drivers and N101 crossover. The crossover was recapped, inductor legs moved and Lpads added to tweeters. Mids were covered and tweeters were shimmed to angle up a bit more. All original cotton batting was intact and in good shape.

I find these speakers to very revealing and enjoyable across a wide range of music in a large somewhat difficult room. The experience of listening to music is enjoyable in large part due to do how all the Bozak parts work as a whole. Certainly amplifier, preamp, TT, CD all contribute their color too but the 302 plays the biggest role in what I'm hearing.

The weakest link would be the tweeters but I don't think they hurt the overall listening experience. I do find myself reaching to adjust the Lpads quite often but I've resolved myself to think of this as a positive.

I recommend them to everyone as speaker to consider but ultimately it comes down to how they fit with your equipment, space and ears.