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Audiokarma
03-26-2005, 07:18 PM
Besides consumer instead of pro labeling, any differences between these?

johnaec
03-26-2005, 07:31 PM
The 077 have the clear plastic insert, the 2405 didn't. The 2405H also have the ferrite magnet.

John

Robh3606
03-26-2005, 08:23 PM
No just the clear insert! You can get the 2405's cheap compared to what 077's demand.

Rob:)

Audiokarma
03-26-2005, 08:30 PM
That's good to know. Is the clear insert the thing that looks like a prism in the slot? Besides appearance, does it serve any purpose?

Robh3606
03-26-2005, 08:40 PM
"Is the clear insert the thing that looks like a prism in the slot? Besides appearance, does it serve any purpose?"

Absolutely thats the phase plug and an intergral part of the driver. That horn will not work properly without it. The 2405's are made of aluminum and are either painted or black anodized. The picture is an 077 with the outer horn ring removed. A 2405 would be the same except the prism would be black.

Rob:)

John
03-26-2005, 09:19 PM
The phase plug is painted!

Mr. Widget
03-26-2005, 09:40 PM
The phase plug is painted!

Maybe some are like that. The ones I've taken apart are painted aluminum for the 2405 and cast acrylic for the 077.

You might find this interesting. As some of us have been saying over and over again about the impedance, here are impedance plots of a pair of 077 "8 ohm" alnico drivers and a pair of 2405 "16 ohm" alnico drivers. All four drivers have their seals intact and are original in every respect.

Red is 077
Purple is 077
Blue is 2405
Green is 2405

Audiokarma
03-26-2005, 09:47 PM
You might find this interesting. As some of us have been saying over and over again about the impedance, here are impedance plots of a pair of 077 "8 ohm" alnico drivers and a pair of 2405 "16 ohm" alnico drivers.

Thanks Mr. Widget. Conclusions?

If a person wanted to throw a pair of either 077 or 2405 in to some 4331 as a project to upgrade to a "4333", would it make any difference?

Mr. Widget
03-26-2005, 09:58 PM
I'm sorry I thought the plot was self explanatory.

The conclusion is that there is absolutely no difference between an 077 and a 2405. There is also no difference between those labeled 8 ohm or 16 ohm. From other tests I have done there is also no difference between the alnico and ferrite versions... at least as far as the 2402, 2403, and 2405 are concerned.

That said there is a fair amount of variation from unit to unit. There is a fair amount of variation in sensitivity as well. I suppose if I were Westlake and I were building $80K speakers I would buy 100 drivers and match a handful and return the rest... actually I believe that is what they do. I know Meyer used to do that when they bought JBL. It is not that these are inferior or poorly made, they just require insane levels of precision and even within their tolerance there is some variation. As you go up in frequency and the wavelengths get really small a slight physical variation has a much greater effect than at lower frequencies.

Widget

Audiokarma
03-26-2005, 10:12 PM
I'm sorry I thought the plot was self explanatory.

Widget

Since the variance in the distribution is so insignificant, I suppose it is pretty self expanatory. Just wanted to make sure I wasn't missing anything. Thx