White dot on terminals. Is this the positive or negative...?

**atilsley** · March 12th, 2013, 05:47 PM

Have old pair of comp drivers...Mlynar (or similar name).

There's no positive or negative marking on the terminals, except a white dot.

Is this positive or negative?

Thanks.

**cradeldorf** · March 12th, 2013, 06:01 PM

I'd guess negative if I had to. Technically you should be able to go both ways with it and just put it to the one that sounds the best.

**HeathKitPat** · March 12th, 2013, 07:02 PM

Originally Posted by atilsley

Have old pair of comp drivers...Mlynar (or similar name).

There's no positive or negative marking on the terminals, except a white dot.

Is this positive or negative?

Thanks.

Remember that with amplifier output you are dealing with an AC (alternating current).. there is really no positive or negative. That white dot could more than likely be used as a reference.. as long as both channels are hooked up the same and the speakers are in phase you will be fine..

**atilsley** · March 12th, 2013, 09:52 PM

OK, got it...thanks.

**Cal Weldon** · March 12th, 2013, 10:29 PM

Use a AA or other small battery. If connecting the white dot to the + on the battery while connecting the - to the other terminal creates a forward cone movement, the white dot is the +

**Alien_Shore** · March 12th, 2013, 10:35 PM

Originally Posted by Cal Weldon

Use a AA or other small battery. If connecting the white dot to the + on the battery while connecting the - to the other terminal creates a forward cone movement, the white dot is the +

Not with HF compression drivers. This test should only be performed on woofers.

**atilsley** · March 13th, 2013, 05:20 AM

The driver is Emilar EA 175, Alnico....any good?

This article seems to suggest so.

Vancouver Audio Speaker Clinic - EMILAR HORNS AND DRIVERS

**Old Guy** · March 13th, 2013, 06:36 AM

White would normally be positive, as black is standard for negative. Actually, there ARE positive and negative polarities in drivers, as they drive the diaphragm in specific directions...

Normally positive voltage should move the diaphragm towards the user.

In the old days, some defined positive as moving away from the magnet. But the diaphragm is on the rear, so this was out of phase.

I beg to differ on the AA battery test, as I have done it thousands of times with no damage. I use to do Pro audio. Not a good idea on ribbons though.

OTOH, since the voice coils are often not equidistant from the user- the horn's coil is usually farther back-sometimes out of phase works better. The listening test should be the final judge.

Emilar drivers were designed by Jonas Renkus, former Altec guy. Yes, he and his son Algis, and now his grandson, are the Renkus in Renkus-Heinz. Algis was also involved in Radian.

**atilsley** · March 13th, 2013, 04:25 PM

Thanks

Can you comment the quality/performance of the emilar?

Some articles I've read suggest they better'd jbl...?! Massive alnico magnet may help.

Kindly

**Cal Weldon** · March 13th, 2013, 05:23 PM

Originally Posted by Old Guy

I beg to differ on the AA battery test, as I have done it thousands of times with no damage. I use to do Pro audio. Not a good idea on ribbons though.

If Alien is worried about too much travel, maybe remove the horn, remove the screws from the diaphragm, hit it with the battery and poof, watch it jump right out of the gap.

Kidding of course.