As I have finished remodeling my new Opera room:

 http://www.GoodSoundClub.com/TreeItem.aspx?PostID=16948

…I modified my Altec 19. The one ordinal that I had was truly phenomenal item. I went to recue what was done in there I was very impressed. The former owner from Florida has reportedly died already but the way how he kept the speaker was truly exemplary.  Everything inside is original and new as it was produced just last week. The new external foam, the new grills, the drivers as they were made just last night. Wonderful! I rotated the bass drivers (a good for suspension sagging) and realized the he put a very thick layer of leather (½ inch) between the bass driver and enclosure. I got rid of the MF driver, put my 18-cell with S2 driver in place driving it from the very same Altec 19 crossover, effectively converting the Altec 19 to Altec 21S. The sound of CD was very nice if I hear it from another room.

Then I decided that I am too expressed and too sophisticated and that I can do much better then the 35 years old stupid crossover. So, I made two second order 500Hz crossovers for 416 driver and S2 with metal cone. As I connected my new Altec 21S with my own crossovers, with use the original one  the sound turn out to be so disgusting that it shocked my “sophistication” to its core. I can not even begin to describe how bad it was and I am very glad that no one witnessed that shame. In the best it sounded like I just eaten a kilogram of rusty nails and then drunk a gallon of Muriatic acid. If somebody tried to apply Muriatic  acid to metal then you know it feels (smells). I was sitting in front of the speakers and was thinking what the fucking idiot I am. I literally was about to vomit not only because the Sound but also because I did it with my own hands (mind).

Well, the result I got, perhaps need to have further working and I am sure that if I go all the way to the bottom of it then I would find a useful combination, but I was poisoned by me “engineering” that I trashed my own crossover, put back the original Altec and said to myself: “You Moron, do not fucking touch it anymore.”  The only thing that comforts me in that whole story is that the narratives of my big “design adventure” is my secret and no one knows about it.

Listening my Altec 21S, even for movies, I do detect that it has some kind of lower MF problem, somewhere within 500-2000Hz. Here is the dilemma, what to do with it in 2–way speaker? Pretty much nothing… Since I use the original Altec 19 crossover my crossover has MF adjustment but Altec adjustment   is within next octave and sonically as I move Altec own EQ then it very horribly reflects sound. I prefer to keep the MF Altec 19 adjustment at zero.

Here is two options that I can see if I willing to deal with it: 1) to drop the MF crossover point from the Altec’s 1250Hz to let say 500Hz, thankfully the 180Hz multi-sell would allow to do so 2) introduction another channel between tweeter and woofer. Both of the ways would do and I “might” try it.

What I wonder if another channels goes what driver it might be. It is not that I am in search mode for driver. I would like to spend no efforts on it and at this point my interest is purely theoretical. For sure my JBL 2490 would be a great candidate for it:

http://www.goodsoundclub.com/Forums/ShowPost.aspx?PostID=15335

I have a pair of them, new sitting in the boxes. The problem is that when I got them I was thinking to use them with my 18-sell 180Hz horn. Now the multi-sell is busy with Vitavox S2 and I have no plans to change MF. So, to engage the JBL 2490 it would need another lower MF horn with 3” entry. I do not have such a horn. If somebody knows any ready to go 3”-entry horn of any profile with 150Hz-180Hz exit then I might try it. I would not custom design and order such a horn as I would like to have the Altec 91 project to go easy and cheap.

To drop the MF crossover point would not be a big deal and I need to try it another day…. Still, the huge amount of empty space above multi-sell with Vitavox S2 drives me nuts… and called to be filled…

The Cat

Markus wrote:

Personally, if I wanted to get a 2nd system, I wouldn't want a less good version of the main system. If they both share an approach to audio, you'll always hear the 3- or 4-ness when you are used to the same thing in 10. I'd try to be as different as possible in the 2nd system, say Genelec 8260A or something in that genre. Or perhaps, since you want your 2nd system for opera, I'd look at what monitors are used in opera production.

Romy the Cat wrote:

As wonderful my Altec 21S plays video and pop crap as much it absolutely impotent to play any classical repertoire. In fat when I estimated it as 3 on the scale of Macondo 10 I meant the video concert and operas that I play on it. With pure audio with more or less demanding material it sinks to the bottom of the barrel.   I played today on the Altec 21S the Adagio form Mahler 6 – probably the most beautiful music Mahler ever composed and Altec 21S just destroyed it to level that it was a pain to listen. I do not need to make those experiments as it kills my libido to entire audio…

miab wrote:

I wonder if the inappropriate settings for 2 channel audio somehow might have affected your experiments with it as a transport in your main audio only system?