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phsf98
03-15-2005, 03:43 AM
hi

Do you guys have any idea about this Altec 422-8z?
It is 15' with aluminium color dust cap.
What is its frequency range, dB rating etc specification. Was it a member of the VOT? I can not find any infor for it beside some website saying that it is the same as the 418B.

thanks in advance
sf

Earl K
03-16-2005, 09:55 AM
Hi sf

- Actually, Altec did refer to the 422-8z as a 418 "type" speaker .

- They also referred to the 423-8z as a 421 "type" speaker .

- FullRange ? Altec always paired it up with a compression driver .

- Sensitivity ? I've never seen that mentioned .

- Both of these "types" were created by fitting up the appropriate magnetic assembly with the Altec # 21605 VoiceCoil/ConeKit assembly ( if the unit was the older 15" frame ) . The 16" frames received the # 23890 "conversion kit".

- This info is all obtainable from the Altec, 1975 Driver Reference (http://www.lansingheritage.org/html/altec/reference/1975-driver.htm) . A lot of this info is from Page 10. (http://www.lansingheritage.org/images/altec/reference/1975-drivers/page10.jpg)

- You can see the cabinets where these hybrid woofs were used. Look on Page 10 (http://www.lansingheritage.org/images/altec/catalogs/1972-mi/page10.jpg) of the 1972, M.I. catalogue. (http://www.lansingheritage.org/html/altec/catalogs/1972-mi.htm) . You can also see these systems ( evolved a bit ) on Page 8 (http://www.lansingheritage.org/images/altec/catalogs/1975-mi/page08.jpg) from the Altec, 1975 M.I. catalogue . (http://www.lansingheritage.org/html/altec/catalogs/1975-mi.htm)

- In response to your query about whether or not these speakers ( 422 & 423 ) were considered part of the VOTT family , I guess the answer is, yes Altec considered them to be part of the VOTT family .

- The 418 had a lighter cone for "lead quitar" usage while the 421 was for bass guitar . Exactly what made these "conversion kits" (the # 21605 & # 23890) different from the original speakers - I don't know, maybe overhung voice coils - just guessing / that's what I would have done since the intended use was in bass reflex boxes. The 418/421 had essentially "0" Xmax (.05") before distortion components would start to add into the sound . Someone like Bill at Great Plains ( or Todd White ) might know about this coil-kit .

- BTW,,, By 1978, it appears Altec stopped using these hybrids . They went back to using bonafide 421-8LF woofs ( & the newly devolped 808-8B driver ) in the 1233 & 1234 enclosures that superceeded the older 1202/1204/1218 types .

My Editorial

- Just be aware; the 422/423 are from a time period when Altec virtually handed JBL the M.I. market by making all the wrong marketing decisions directed at musicians . Speaker Systems ( ie 1202/04/1218) were one of those "mistakes" ( IME ). Leveraging the VOTT marquee was not a great idea. Creating the wimpy 807 driver out of the larger 808 type was a mistake. Pairing that 807 with the 422 (or 423 ) was another mistake. I was a working musician for much of the 70s' - and saw/lived these market devolutions as Altec cheapened their product lines ( perhaps mistakenly thinking that was generally where musicians fit into "their" food-chain ). By 1977 I was buying JBL components that didn't give up the ghost after the first squeal of feedback . Yes, "Just Be Loud" meant a 4" diaphragmed driver - mated with twin 2402 bullets .

Oh , I do love 288 drivers .

To be fair to Altec, the 1215a & 1225a (http://www.lansingheritage.org/images/altec/catalogs/1975-mi/page10.jpg) were very good portable High Performance SR offerings. The 292 driver was a phenolic diaphragmed version of the 290 type and was aimed squarely at the (loud) M.I. market. But again, since Altec didn't market a hi-power tweeter to accompany this combo - they sent their "users" over to the "JBL counter" to buy adhoc "bullet-packs" . Another marketing mistake for a good product . The 1215a was certainly able to generate a lot of clean LF "impact" .

:cheers:

phsf98
03-16-2005, 04:44 PM
hi Earl,

thanks a lot for your information. This is indeed a very good one, cause there are almost '0' information about the Altec MI speaker around the web. Maybe there are but i couldn't find it.

However my concern about this speaker is wheather they are suitable for music from hifi equipments? What is their main differences between the MI and hifi speaker from altec? I come across some post in the other altec forum that the MI speaker add distortion to hifi. Also something to do with the X max thing. Could you kindly tell me what the Xmax going to affect the music reproduction and frequency response?

thanks a lot again.
with regards
sf

Earl K
03-16-2005, 05:19 PM
What is their main differences between the MI and hifi speaker from altec? I come across some post in the other altec forum that the MI speaker add distortion to hifi.

M.I. speakers are engineered so that under some assumed operating conditions, the coil is being used ( driven ) a certain percentage of displacment "out of the magnets' gap" . This ( out of gap ) displacement adds distortion components to the sound that the guitar or bass player hears ( & hopefully wants ) . The onset of these distorted conditions is usually engineered to occur a lot quicker than speakers specifically designed for low distortion, HiFi listening .


Also something to do with the X max thing. Could you kindly tell me what the Xmax going to affect the music reproduction and frequency response?

See above.

Personally I wouldn't chase down getting a pair of these speakers to listen to.

But,,, if you have them , then put them in some vented boxes and take a listen. You just might like them. Try 4 to 6 cu' boxes tuned to about 45 hz .
If you keep your listening levels to a reasonable volume ( below 100db ) you just might never hear the inherent distortion from this guitar-based speaker .

You can get free tuning software on the net if you look around . Forget about getting Ts parameters on these woofs ( just so that you can look at simulations ) - SIMS aren't going to help you decide much of worth in this case. You are best to just build and take a listen.

Go to this web site (http://www.psp-inc.com/) and use their vent tuning software to get some sizes & lengths .

:)

phsf98
03-29-2005, 09:01 PM
hi there,

thanks for the infor for Altec 422 MI again.
I found the biflex speaker more suit my need, with a more wide response.
However do you have any idea of these biflex variants, TS parameter and so on?
Altec 419A, 419-8A, 419-8B
Are there any difference between these model? Will a open baffle operation suit these speaker? I found that the Altec model naming is a bit of confusing.


thanks
sf:barf:

Earl K
03-30-2005, 06:09 AM
However do you have any idea of these biflex variants, TS parameter and so on? Altec 419A, 419-8A, 419-8B

- No, I don't know about the different variants. I assume the 419A was 16 ohms while the "8A & 8B" were 8 ohm evolutionary derivatives .
- What I know about these speakers is just what I found in the Lansing library. Look here to see all that I know about them. (http://www.lansingheritage.org/html/altec/specs/components/419-8b-420a.htm)
- Look through all the older ( 50s to early 70s ) Altec catalogues (http://www.lansingheritage.org/html/altec/catalogs/altec-cat.htm) to get a sense of the evolution of these speakers. They first appeared in the early to mid 50s' without the metal dome in the center. The first 12" model was called the 412-8a . Do your homework and you can get a relative recommended enclosure size from these catalogues. Also note, that even Altec recommended that users should consider adding a tweeter in the form of a H3000 kit. That ought to imply something to you about these models HF performance .



Are there any difference between these model?

- See above.


Will a open baffle operation suit these speaker?

- I don't know , but I suspect not.
- Do ask over at the High Efficiency Forum of A.A. There are some people there that are into open really baffle designs.
- FWIW: From what I gather, these open baffle guys are usually looking for speakers with a fairly high Qts - like around .8 & up . That should exclude Altecs' large drivers since they are mostly all derived from theatre products where very low Qts figures dominate ( less than .3 ) the Ts figures. It's the large magnets that JBL & Altec used that helped create the low Qts figure . Maybe you should be looking for speakers with more weeny-sized magnets.

:)