Altec A7 measured...

[Alien_Shore]

a7-response-cd.png
This is crap. I've only been measuring for a little over a year, but given that the author shows no information relative to his test rig or methodology, and then doesn't even question such an apparently awful result shown in this frequency response other than to say "there is a major problem with the horn" is amateurish at best.

[GM]

Being a truncated horn, its response is actually 'rippled', so should be a series of peaks/dips out to the throat cut-off around ~478 Hz, but when there's a good driver/horn match, it should be nominally flat out to at least 1 kHz, so a prominent peak around 200 Hz with a decaying response typically has either a driver with too high a Qts and/or one that for whatever reason has the wrong break-up modes BW, both of which occurred in later years when non optimal 'sub' woofer drivers and high power rated compression drivers were substituted for the 416, 421, etc. in the prosound models to apparently make the most of what they had available, though by then, digitally EQing the sound system as much as required had become the norm.

GM

[paul300b]

What bugs me most is that somewhere in the future somebody will cite/post this article to objectively qualify their opinion that all VOT's sound bad.

You know the deal, if somebody said it on the internet, it must be true especially if it was written in an article.

Agreed. Someone should post on his comments page. But the good news would mean the price of Altecs would come down in our part of the world.

[VolvoHeretic]

Agreed. Someone should post on his comments page. But the good news would mean the price of Altecs would come down in our part of the world.

Agreed. Spred the word how crappy Altecs sound. Cut them down at every chance. My musical instrument Altecs still sound great, and the price was also great.

[vuki]

6 years back

[fpitas]

6 years back

Worse yet, in the intervening time we've all been quietly EQing in a 45dB peak at 5.6kHz for our 511s, without giving the guy any credit, now that we've seen the light.

[atilsley]

I reported some of these posts back on Stereonet in Australia, in response to the article Paul posted on an Altec midd bass horn I was working on.

See here -

Pics New Mid Bass horn using CNC, Altec, fun.... - DIY Audio Projects - StereoNET Australia

One gent posted this graph showing similar horn (details to follow), highlighting the very issues Paul was alluding to, suggesting:

"What's that in the orange response there?!?! A cancellation. Yes. It's supposed to be there. Measurements at the horn mouth will not show the cancellation. Paul was quite clear that the speaker needed a super tweeter."


Andrew