Altec 755E: too many questions

[GM]

Hello GM,
Hello mah,

PM sent to GM.

Greets!

Please edit this post to include anything related from the PM that's missing since regardless of whether any others respond, I want it [hopefully] preserved long term for lurkers, folks Googling/whatever for info long after I'm gone.

GM

[Tralalalala]

GM; I find your last replay quite remarkable.... ;-)


JElabs remarks that 5/8inch / ( 15mm ) low grade plywood is more than adequate ; but 1/2inch ( 12mm ) is too slow.
I was pondering about using 9mm on all sides, see earlier quote / REF from junkyard jukebox in my opening post ( dont know the correct label for 9mm is in inches ) : after reading both blogs more thourugh :

Will build everything in 5/8 ( 15 inches ) high grade pine plywood; everything should fit on one standard sheet of ply; 4ft x 8ft (1220mm x 2440mm )

[mah]

Read only the Zilch posts: Building Altec 755e Speakers

If adding a tweeter is too hard, consider these @ $150ea. 305P MkII Products | JBL Professional Great reviews. Built-in amps.

There are 6" an 8" (306, 308)models.


Hello all,

To be honest; I thought this forum was no longer living; after a ( way too ) quick google search I did not find you --I did remember that I joined the forum several years ago and got a lot of help regarding my DIY 612 utility cabinets for my Altec Lansing 604E Super Duplex drivers. My Duplexs are no longer in my possession , with a much too low WAF, and still not having the possibility of having a dedicated hifi room...

Today I have a new pair of drivers; I am very eager to learn more about these drivers; a pair of 8" NOS Altec 755Es. I have too many questions, and I have already tried my luck at the lansing heritage forum ( NOS Altec 755E: Q: CABINET / AMP / TWEETER? ) ; after the last replay to my thread, I was redirected here; I am crossing fingers that this will be a more suitable place for my questions.

INFO:
I got my interest in these drivers after seeing on net a pair of reissues of the 755As ( alnico ) from LM Audio; based on the Western Electronics 755A ( see ref for more info about these reissues--I, myself, have no affiliation to LM Audio )

Q1. My 755Es measure 6.6ohm and 6.9ohm; will this 0,3ohm difference in resistance affect sound? The specs on the 755E says 6.8ohm

I will make a cabinet based on the Altec 618. It will be made of high grade pine plywood. All sides in 9mm ( 1/2 inch= 12mm ) so this is by far the thinnest cabinet Ive made, but Ive read on net that some of the original 618 cabinets were made out of 9mm ply. I will rear mount my 755Es. I will reinforce the cabinets as shown at this site / most of my info about how I wanted to do my cabs are from this site: REF: Junkyard Jukebox

Q2: What kind of material should I use as damping / it looks to me that these original 618 units did not have much damping material?

Q3: I have not found / read much about matching between amps and the 755Es. What kind of amplifiers should I consider?

Q4: I have understood that the 755Es do ( need ) work well with different tweeters. I do got a pair of Decca Super Tweeters ( ribbon tweeters ) with a range of 7KHz- 30KHz, Crossover at 7 KHz, Efficiency : 88db at 4W at 1meter. Is this a plug & play unit with the 755Es? ( For the record: I do have very little knowledge about integrating tweeters / subwoofers with my gear. )


All inputs will be greatly appreciated.[/QUOTE]

[Tralalalala]

Maybe I was barking up the wrong tree ....

This is my PM to GM ; in its entire form: --dont like being cornered like that; nobody does , I guess....
There is not much more in it compared to post #9.

Hi GM,

First : I wanted to thank you for answering my questions online.

Second : I have understood that the Altec Users Board is looking for a new home + the site, well..., in its current state, has been on and off and is quite difficult to use for many members.

Third : Im sending you a PM since I found it a bit strange having just a two way monologue open for all eyes and ears when it was just the two of us writing:
Me asking eagerly and with broad questions and you trying the best you can to answer ....

Ive found out where I read about the tubes equals GCs : op-amp : I got it all turned upside down. Maybe youll find the article interesting. I meant to say: low wattage Solid State Class A : like the Amp Camp Amp by Nelson Pass; it is a low-cost kit I would have managed to buy without breaking the bank + and a kit I would have managed to build myself.


I got my 755Es in the mail today; they both are in very good condition :-)
I have a NAD 3120 ( a version of the NAD 3020B without tone controllers ) + a refurbished Quad 303+Quad 33 ( pre ) that I will first try out with the ALTEC 755Es.

I think I will leave the thread as it is + and not do anything about tweeters.

Three last questions from me:

Q1: Have you ever heard the 755E? Sound impressions / after your opinion: will it work well on its own without tweeters; this will be apart of a living room stereo; mostly jazz , small ensembles, singer / songwriter, classical music ( small ensembles )

Q2: Considering 12mm pine ply instead of 9mm : pros / cons ?

Q3: The NAD3120 / The QUAD303+33 - any other integrated ( sub 500USD ) amps that jumps into mind?


Thank you again for helping out...

Best regards,
Tralalalala ( NORWAY )

goodbye

[GM]

( dont know the correct label for 9mm is in inches )

9/25.4 = 0.354", so between 5/16" = 0.312" and 3/8" = 0.375", ergo much too 'lossy'/resonant.

GM

[tomt]

9/25.4 = 0.354", so between 5/16" = 0.312" and 3/8" = 0.375", ergo much too 'lossy'/resonant.

GM

too late.

hes gone.

see the 'goodbye' ?

[GM]

No, I didn't till now, I'm so 'gun shy' nowadays from lost postings, etc., that I do my postings off line and copy/paste, then going to the next one in sequence as time permits. Oh well, I intend to finish what I started, maybe others will benefit eventually. If not, it at least keeps me distracted from [currently] crippling sciatica in both legs.

GM

[Phil-G]

"Goodbye''

well that was weird.

[mah]

"Goodbye''

well that was weird.

Agree.