416's vs. 515's

[GM]

>GM, also Am I reading your reply that the 416 or 515 has the higher Q? The way its written, it seems you are saying the 416 has a higher Q? According to altec the 416 is lower both in Q and Fs. OK, I'm unpack the 515 and am going to rethink this... any input for my application would be appreciated, I want to hear the 515 (which I thought Altec used in the A-5) in their best possible light. sorry to be confused but if I have it right, I think we are in basic agreement but you own findings are that the 515 can be a good BR driver, but EQ must be applied for it to work properly? Any direction is appreciated.

Russellc

====

Greets!

OK, we're having a 'failure to communicate'. In re-reading my posts I can see where I might be sending some mixed signals. My bad.

When I think 515 series I'm thinking low Fs/Qts horn driver, with the 416 series being used for everything else since I think of the A7 as more of a tweaked BR than horn cab since its 'horn' is just a transition piece to better blend the HF horn to the BR. You could just as easily use a second driver, with the added advantage of increased LF gain. At the time the A800/A7 was designed it wasn't needed so there was no point in having one more component to potentially fail at an inopportune moment.

That said, the 515-8G came out long after I quit actively building using Altec components so I tend to forget that it apparently was designed to be a 'jack o' trades, master of none' for prosound apps that use SS exclusively, so has a higher Fs for horn loading than the 416 series yet has its medium low Qts so is somewhat more limited in alignments than the 416 series.

The rest of the 515 series though is the most flexible of the bunch and has the 'fastest' diaphragm (least mass), hence why I prefer it for most apps. BTW, I've used dozens of 515Bs and they all had an Fs down around 20Hz and Qts around 0.2 so I don't know what gives with the published specs.

Yes, the earlier 515 series was used in the A5 and with no series R are decidely bass deficient compared to the 416/A7 versions. In doing a sim of the 416-8C and 515-8G in an 828 though, the 8G has a ~aneochoically flat response while the 8C has a peaking one so I can see now why you hear more bass response from it. Of the two, I prefer what I'm seeing with the 8G since it's a much more damped response, but for folks who prefer the extra 'sizzle' of the 'West Coast' sound, the 8C appears to be the better choice. Or if they use an 8C, but want the flatter response they can lower the cab's Fb by reducing the vent area to suit.

WRT BR, etc., apps, again, I prefer the 515 series since they have a lower Fs/Qts (all the ones I've used anyway) which allows for more design flexibility and has the added perk of having the better impulse response of the two series, hence can 'keep up' with HF horns better than the 416 series. The 'mixed bag' 8G is somewhat more limited since it has a relatively high Fs, but still my preference over the 416-8C since I can tailor it with EQ to get better damping with ~ the same gain/BW in less Vb (at least on paper).

All that said, I have no experience with GPA's re-cones or seen any detailed info on them so all this may be moot if you don't have originals in good condition. For all I know they use one re-cone kit for both series, which would mean that the only difference would be relative motor strength. This would still make the 515 series the more flexible of the two, though not as much as with the originals.

GM

[GM]

> Hello GM,
Now you have really got me wondering. Guess I'll listen closely to several selected cuts a few more days and then switch to the 515s for a re eval, but I can definatelysay that the bass is deeper and "seems" tighter with the 416 8c than the 515 8G in my setup, and of course, to my ears. My current recollection is the 416 is tighter and somewhat more "hi fi" than the 515, which strikes me as more lush
and well, for lack of a better word, exhibits more "majesty". with the standard 7 or 8 inch port width, male voices are "boomier" with my 515 than the 416. they have been reconed by Bill when I bought them, with what appeared to be original cones, I'm sure they are not, but they had that original greyish color and original altec numbers. One got cat scratched and I sent it back and it came back with a slightly different cone, with a number begining with "GPA" which was more "blackish" in color. It plays fine, but things like that bother the heck out of me. Oh well, I,ve got some listening to do!

Russellc

=====

Greets, part deux!

I don't know how to respond to this, I mean I've never heard a 'boomy' 515 (including the higher Qts 8G) nor a 416 series that sounded 'tighter' than the 515s and the specs give no indication they ever could be, plus the advanced sims I've done imply that they perform the exact opposite of what you're hearing, so I have to wonder what sort of 'animal' you get with a GPA re-cone.

One thing's for sure though, after this thread's revelations, someone will have to pry my matched set of four 515Bs from my cold, dead hands! Makes me wish now I hadn't sold my other four.

GM

[gearjammer]

You do not have to recone to re-magentize your drivers or woofers. Also unless you drop your driver from 6 feet to the floor in which case the magnet will be broken or shifted or you smoke your coil and it catches on fire chances are your magnets are fine. It would take about 100 years in a normal hi fi listening enviroment to notice the effects of a weak magnet, which by that time you will be dead and the rest of the cone assembly will be dust. Maybe if you crank your speakers to 115 db. for 10 years on a steady basis you will weaken the magnet but by then your ears will be shot as well.

[Altec19]

I have a pair of 416-8B's that spent their lives behind the screen of a movie theater. I listened to them for a while and then brought them to GPA for remagnetization. The difference was so apparent that even my grade school aged kids noticed the difference. De-magnetization is like bad shock absorbers on a car. You don't realize how bad they are until you replace them.

[Russellc]

GM,
Thankyou for your detailed responses, everything you said makes sense, including the part about the cones. I think I have a local friend that who has some original altec cones. If possible I'll purchase them in hopes that I can find either someone to do it correctly or eventually someone on this board designs some "fitment/fixture/shim" contraption allowing someone such as myself to do it in a "nonsinking" fashion.

Thanks again, Russellc