Q: 515-G series vs. 515-GHP series

[N.B.C.]

Hi All,

1) What are *all* the *specific* dfferences between 515 'G' and 'GHP' series?

2) How do the voicecoils, magnets and cones differ?

3) Any disadvantages of GHP series compared to G series?

4) Cannot find specs for a 515-GHP. Does someone have them?

5) Searching archives, someone listed specs I've copied and pasted below for 515 8G and 8GHP.

.....a) Are the sensitivity specs the person listed for free-air, or horn mounted?

.....b) Excurison values between those specs and the attached Iconic PDF differ. Is "maximum excursion" the same as "Xmax"?


[[515-8G]]

Sen 103dB
DCR 6.2 ohms
Qts .269
Qms 5.0
Qes .284
Vas 12.4 cu ft
Vd 22.4 cu in
Max Excursion .7 in peak to peak


[[515-8GHP]]

Sen 104.5dB
DCR 5.6 ohms
Qts .187
Qms 4.5
Qes .195
Vas 12.1 cu ft
Vd 15.8 cu in
Max Excursion .85 in peak to peak


GPA lists 515G-series T/S specs here (accept 515-16GHP): http://www.iconicspkrs.com/downloads/165series.pdf


6) How do I convert GPA-listed "reference efficiency" into "db/w" sensitivity rating?
.
.
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I know its a detailed post, so thank you for any assistance.


Neil

[LICORNE]

Hi,

You will find most of the answers here.

http://www.lansingheritage.org/image...515g/page2.jpg

Your last question maximum excursion and XMax are not the same in theoretical jargon.

I did not have time to check ICONIC 165 yet.

.................................................

[Old Guy]

The 515G is more in the vein of the classic Altec "woofer". Works well in boxes like the 828 and so forth. Very good horn loaded type speaker.

The HP version uses a different cone. It is more of a "musical instrument" type of speaker. Obviously handles more power, at the expense of bandwidth.

As I've posted, I am not a fan of the "HP" speakers. I feel the designs and sonic quality have been compromised in favor of power handling.

[N.B.C.]

Question #4 should read, "I cannot find specs on 515-16GHP."


Neil

[LICORNE]

Hi,

Altec Lansing Pro did make a 515 8HHP 16HHP.

Not all data on spec sheet of "discontinued" product. GPA would be the best place for information on new product.

http://www.altecpro.com/pdfs/515_SS.pdf

http://www.greatplainsaudio.com/

...........................................

[Old Guy]

Are we sure Altec Pro actually made any of those?

In its short existence Altec Pro sold very little. Several people who I know signed up as dealers recieved no product at all.


I know they had 604's made by Great Plains. And I've seen a few other things, but frankly not much.

[Old Guy]

I did have a little fun poking around Altec Pro's sit. I HAVE to crack a smile at products from just a few months ago being discontinued and called "vintage"

It's kinda like drinking an American beer and commenting July was a great vintage...

[bfish]

I've always been under the impression that the only difference in all 3 is the voice coil, which Altec's published TH parameters seem to bear out. I've been wrong before though, so would also like a definitive answer. It seems to me that the HP needs to "see" a heavier acoustic load than the others for peak performance, making it more limited in application, and therfore more prone to being 'dissed' if improperly applied (i.e., in oversized, leaky, or non-horn-loaded cabs). Maybe I'm putting too much stock in Altec's claim that the 515-8GHP was the most efficient cone driver they ever produced.....

Old Guy, I've noticed your disdain of the "HP series" in previous posts, but I'm only aware of the "HP" version of the 515-8G. Were there ever any other "HP" models, other than AlPro's so-called 515-HHP (which I suspect is merely a relabeled -8HP)?

Have to agree with your feelings about AlPro, though I'm grateful they helped provide GPA a little income, even though they took the credit for GPA's work.

Also agree that July was a good vintage for beer...I had one last night that had been neglected in the veggie drawer since May...tasted too much like the can.....

[N.B.C.]

Convergence: Is that 515-GHP made in China, or did/does GPA make it? Did Altec ever make that driver, or does GPA?

Old Guy: My *only* interest is in sound quality. How would you descrbe the tonal characteristics of the G-series and the GHP-series?

Does the GHP use a heavier cone, and how does the voicecoil differ?

Thanks for any insights,
Neil

[GM]

Originally posted by N.B.C.:
5)

.....a) Are the sensitivity specs the person listed for free-air, or horn mounted?

.....b) Excurison values between those specs and the attached Iconic PDF differ. Is "maximum excursion" the same as "Xmax"?

6) How do I convert GPA-listed "reference efficiency" into "db/w" sensitivity rating?

<font size="2" face="Verdana, Helvetica, sans-serif">Greets!

They appear to be half space like is normally published even though they state free field.

Max excursion normally refers to the suspension limit (Xsus), which is usually right before it bottoms out (Xmech).

I'm kind of math challenged, so this is the only way I know how to convert it:

dB/4 ft = ((log(10)*110.297)+10*log(eff))/log(10)

dB/m = (dB/4 ft) + (20*log(4/3.280839895))

GM