New 802-8G from GPA

[Altec Best]

No i have not. That will probably take place after the summer.

[quote]

This would be quite interesting and would very much like to see the results.The only way to do a comparison is to do a Blind Comp.So you will need someone to help you.If you know what driver,Fram,etc. you are listening to that could cloud your judgment.When I did this years ago when my hearing was a little better.My preference was always the 802-8G w/23744 and keep in mind I didn't know which drivers I was listening to.I would go into the other room and a buddy of mine would switch up drivers and time after time I would pick the 23744's that did it for me no question.When we were experimenting when putting a system together drivers wise.

Brad's wisdom inspires an objective investigation.

Agreed ! Brad knows his S$#@ And is one of the people I would ask for help if needed.But I was talking strictly as my personnel preference.

I've encountered are that the failures have all been due to broken lead ins near the center of the flexible portion, never a fractured dome, surround, or burnt coil in my limited experience. In fact, i have a 604 with both lead ins broken on the 23744, how does this happen?[/

QUOTE]

Me too.It is always the wire leads that break first as this is the weakest point in the small format "Frams" . Over time the wire leads will develop right angles on the leads.When this happens they are toast.I asked Bill about this when the wire leads have nice curve to them they will still have plenty of life in them.And this is the first thing to look at when determining a Frams life if leads are at right angles like the letter "L" that wire will break at the bend when it fails.How long or short will it live "Who Knows" ??? Dave "Wojo" has repaired a couple for me. He's pretty good at it.The extra metal on the leads added .2 ohms resistance acceptable.


Michael V - I agree with you that they do sound a bit better, but better !!

[Panomaniac]

If someone does get a chance to point a mic at them and measure, it would be great to see distortion measurements. That might say a lot. ARTA/STEPS would be a good choice for this, and/or HolmImpulse.

[bfish]

...This causes me to reflect on discussions of the 23744 in years past where it was never stated conclusively what the differences actually are between the 23744 and 34647, and to the best of my knowledge, we're still a little in the dark to date...

Yeah I remember that too. This old thread was a big part of it;

http://www.hostboard.com/forums/alte...odel-19-a.html

The Zilchster put a mic to one too. The limited comparison may have raised more questions than it provided answers, but it's still an objective measurement;

Look at my new babies...Altec 846Bs w/EV Tweeters!

If one sorts the objective information from the fluff in all that, there are a few constants. The 23744 does appear to go a bit higher, but it does it by turning belly up on the other end where the fundamentals are. Altec only used them for high-XO apps in M19s, Duplexes and similar (see the '75 reference), where the weak bottom didn't matter (as much), and the HF extension could be used to advantage.

So, while it might be safe to say the 23744 was the hot ticket for M19s and Duplexes, implying that it's the hot ticket for any 1" app (which is where the webmonsters have taken it) is simply wrong.

I second Pano's suggestion for distortion measurements. If the 23744 is indeed of thinner material, it will be more prone to breakup modes. A simple pink noise sweep doesn't differentiate between pistonic response and low order distortion.

Or, one can take the copout route like me and note that Altec quit making them after a brief period, and assume they had a good reason.

(If they were truly worthy, they'd have been carried over into the MR902HF...)

[Altec Best]

(If they were truly worthy, they'd have been carried over into the MR902HF...)

They were carried over from the 604-8G to the 802-8G and then to the 806-8A

It could also be said that like everything else that is manufactured if no modifications are made then no progress is either.Just a way to make money (Marketing)

Why else do they keep changing models,foilcals,frames,15",16",diaghrams,voice coils,cones,etc,etc.....

But I like all the points you make as well but to these ears they just sound right to me.I dunno

It is truly amazing that even after all this time no one has ever under taken this and did all the measurement comparisons.To say one way or the other what they are actually measuring at.

But again to my ears they sound right.And I'll admit that the last 2 small format systems that I had a chance to listen to for some time is my M19's and 604-8G's that came stock with those Frams.

OK gentleman who is going to undertake this little experiment.

I'm trually looking forward to this,so maybe I can answer a question to myself as to Why I like these Frams over others.

Fire Up your Microphones Gentleman let the Testing Begin ! Or is it start your engines. :coffeedrinker:

[voice of the theater]

(If they were truly worthy, they'd have been carried over into the MR902HF...)

My understanding is that 23744 was only found in early 802-8G's(as well as in a special version of the 806, and early 604-8G's), it was discontinued after just a couple years of production and replaced by the 34647 std aluminum phragm that GPA still produces today.

I understand that the 23744 was the stock diaphragm for the Model 19's (at least for most of them). If it wasn't carried over into the MR902HF -- does that mean it wasn't the stock diaphragm for the Model 14's? Was the 34647 the stock diaphragm for the Model 14's?

[sba2]

CORRECTED DATA --.

Altec 802-8g on a finless 511 horn (measured at 4 feet - 1/24 smoothing) :

Attachment 995
http://img301.imageshack.us/img301/4374/80240.png


& connected to a Z19 crossover, with an 8r dummy load on the LF:

Attachment 996
http://img220.imageshack.us/img220/4072/802net40.png

[Panomaniac]

Nice work! Your measurement set-up must be pretty good, you're getting consistent results. HolmImpulse is a good program to use.

That falling high end isn't bad at all. It's 6dB/octave as far as I can tell. A simple bypass cap across the L-Pad will fix that. It's classic.

Off-axis isn't bad, either. The high end does drop faster off axis than on, but the 30 & 45 deg plots track each other. That big on-axis hump down low is the main worry and must be what I hear as "forward" and "honky".

I'll have to dig up my measurements to compare. I only did on axis, tho.

:thankU:

[Altec Best]

Nice work! Your measurement set-up must be pretty good, you're getting consistent results. HolmImpulse is a good program to use.

Nice big charts that you can see/read hint hint I agree nice !!

[bfish]

... 1/8 octave smoothing has been applied...

Which does a neat job of hiding those nasty "twin peaks" in the last octave I mentioned earlier.

Yeah, the 6dB/oct bypass would get the on-axis trend going the right way, but the problem is it boosts those nasties an equal amount...

(especially if those peaks are really the resonances I suspect)

[Panomaniac]

Would they be that bad? I don't go beyond 1/6th octave myself, as I find it doesn't jibe with what I hear. If I were a manufacturer, however....