Bozak B 302A help

[srs735]

I just picked up a pair of Bozak B302A Mediterranean speakers at a church yard sale.

It will probably be Monday before I get them unloaded, so the picture is the one from the CL ad.

When I looked at the back of the speakers it doesn't have normal binding post. Instead it has two screws

There are no marking for positive or negative. Instead on one of the speakers there is a label with the numerals "1" and "2"

I will use a AA batter with 2 jumpers to check. Off hand does anyone know whether "1" is ground or positive?

The cabinets are rough, and I don't know what the insides are like yet. I really like the wrought iron looking inserts on the grilles

Thanks in advance for any help
Stuart

OOPs, I can't add the pic to this thread as I've already posted it here: http://www.audiokarma.org/forums/showthread.php?t=540123

 

[mfrench]

1= +
2= -

 

[srs735]

1= +
2= -

Thanks for the quick response

Wow, I would have guessed the other way around. :scratch2:

Good thing I didn't bet anyone

 

[blhagstrom]

Doesn't matter (1 +/-, 2+/-) as long as you do them both the same.
Audio is an AC signal.
Hooking them both the same way keeps them in proper phase.

 

[Brian]

Also depends on whether the system as a whole reverses phase on the output compared to the input. Sadly, most source material does not adhere to any uniform standard for phase shift so the whole issue is academic. As stated, just hook the common of each channel to the same screw of each speaker and the positive to the remaining.

The 302a is a really good speaker when up and running correctly. The tweeters are mounted in front of the woofer so, are quite low and usually too low so experiment with tilting the front so the tweeter dispersion is within the sweet spot of where you listen. I simply use a couple of 2x4 blocks under each leg in my room and setup.

The caps in mine were good last time I checked but you may find yours may need replacement. Check with Pat Tobin on the Bozak User group on Yahoo and he can help with the crossover and even may have an updated crossover for the 302.

These do not need goobs of power and I find 20-25 watts rms plenty. The spec for them is 100 watts rms but due to their age I'd suggest respecting them and not try to blow out the drivers getting them to Klipsch levels.

 

[srs735]

Thanks for the wonderful input

I will try to get them out of my vehicle tomorrow and take pics.

As I've read about the B302A's I've seen a lot of talk about early and later model drivers. So I did slide them out of the vehicle enough to look at the build date. It's 692 so I'm guessing that's February of 1969. They are consecutive serial numbers G19961 & G19962. I did check for continuity across the speaker inputs and one was approx 8 ohms :yes:, the other was disappointing at around 6 ohms . I wonder if I'll have time to open them up tomorrow and look?

I've read about people putting the tweeters in a separate box on top of the cabinet, if any one has pics they're willing to share of that I'd love to see them

Thanks again,
Stuart

 

[Gang-Twanger]

Also depends on whether the system as a whole reverses phase on the output compared to the input. Sadly, most source material does not adhere to any uniform standard for phase shift so the whole issue is academic. As stated, just hook the common of each channel to the same screw of each speaker and the positive to the remaining.

The 302a is a really good speaker when up and running correctly. The tweeters are mounted in front of the woofer so, are quite low and usually too low so experiment with tilting the front so the tweeter dispersion is within the sweet spot of where you listen. I simply use a couple of 2x4 blocks under each leg in my room and setup.

The caps in mine were good last time I checked but you may find yours may need replacement. Check with Pat Tobin on the Bozak User group on Yahoo and he can help with the crossover and even may have an updated crossover for the 302.

These do not need goobs of power and I find 20-25 watts rms plenty. The spec for them is 100 watts rms but due to their age I'd suggest respecting them and not try to blow out the drivers getting them to Klipsch levels.

How about raising them OFF the floor entirely instead of just tilting? Does that work with those? I've seen a couple people do it, but I can't attest to the results.

And I agree in terms of going easy on them and not cranking the living bejesus out of them. Those aren't top-end, quarter-mile machines. They're cruising vessels. Think of them like an old '55 Thunderbird. You're probably not gonna' pitch it broadside and drive it with the throttle too-often.