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ictwoody
12-11-2017, 12:51 AM
Hey guys. I have a question.

On my onkens which i purchased, didn’t build myself, they were using a recapped pair of N-501-8B networks with 902-8 CDs and 511 horns. They always sounded pretty good to me. Now the upgrade bug has got me and I bought a set of Jabo KH-55 horns with 1.4” adapters and some Altec 288(C’s I think) on them.

I am running 416Z’s on the low end that are getting reconed to 8ohm drivers by GPA.

My question is are the N-501-8Bs a good choice for this combo in a 360L Onken enclosure? Or should I sell them and persue a better option for my combo? Technical stuff like crossovers is a dark art to me and I just need to know what to do.

Thanks!

- Woody

Earl K
12-11-2017, 06:06 AM
My best advice is to simply try it ( listen & then maybe measure it's acoustic effects if you want to get serious about trying to make this stuff work ).

This ( N-501-8B ) network might work very well ( or at least good enough ).

FWIW, I've never seen a complete schematic for this crossover /// so it's impossible to predict it's interaction with your chosen horn/driver combo .

( Obviously ), this combo is not part of the Altec handbook, so some response errors are to be expected ( in a custom lash-up such as your are implementing ).

:)

gdmoore28
12-11-2017, 12:28 PM
I'll bet the 288/Jabo/N501/416 Onken combo will sound nice.

Earl - I hate to sound like a broken record, but do you think that adding the Altec 30923 eq network after the N501 will work as well with the 288 as with the small format drivers? Both formats seem to have the same highly accentuated midrange response.

GeeDeeEmm


Pic from here: http://theartofsound.net/forum/showthread.php?13734-Jabo-horns

http://farm9.staticflickr.com/8004/7563587814_3c5d4d588a_c.jpg

Earl K
12-11-2017, 04:18 PM
GDM,

The N501-8B may already have the 30923 ( padding with some mild HF contour ) built into it.

That's the speculation ( anyway ) according to this older thread on the subject. (http://www.audioheritage.org/vbulletin/showthread.php?25254-Help-on-Altec-N501-8b/page2)

The info is not corroborated of course ( that's nothing new regarding older Altec stuff ), but there are some strong inferences .

The Jabo ( type ) horns additionally focus the HF into quite a laser beam ( compared to a 511 ) bumping it upwards >> therefore the need for full HF compensation is likey mitigated vs say the typical Altec sectoral/radial ( which needs more help in the HF ) .

That's why I replied earlier, it'll likely "be fine" ( conditional to individual taste , obviously ).

:)


Ps; There's just no substitute for making personal measurements and then using them to identify one's own preferences.

ictwoody
12-11-2017, 10:29 PM
I really need to get the equipment and learn to measure in room I suppose. Is there software to do it that is Mac compatible? I haven’t owned a PC in 15years.

I was was hoping for a more definitive answer than “try them” :-) but I kinda figured that’s what you guys were gonna say. Haha!

i guess I need to get these all put back togeather and then give them a try. Hopefully soon.

- Woody

79326



GDM,

The N501-8B may already have the 30923 ( padding with some HF contour ) built into it.

That's the speculation ( anyway ) according to this older thread on the subject. (http://www.audioheritage.org/vbulletin/showthread.php?25254-Help-on-Altec-N501-8b/page2)

The info is not corroborated of course ( that's nothing new regarding older Altec stuff ), but there are some strong inferences .

The Jabo ( type ) horns additionally focus the HF into quite a laser beam >> therefore the need for ultra HF compensation is really quite mitigated vs say a typical Altec sectoral/radial .

That's why I replied earlier, it'll likely "be fine" ( conditional on individual taste , obviously ).

:)


Ps; There's just no substitute for making personal measurements and then using them to identify one's own preferences.

Earl K
12-12-2017, 05:30 AM
I really need to get the equipment and learn to measure in room I suppose. Is there software to do it that is Mac compatible? I haven’t owned a PC in 15years.

I was was hoping for a more definitive answer than “try them” :-) but I kinda figured that’s what you guys were gonna say. Haha!

i guess I need to get these all put back togeather and then give them a try. Hopefully soon.

- Woody

79326


"FuzzMeasure" (http://supermegaultragroovy.com/products/fuzzmeasure/) is the most common ( & stable ) Mac-based measuring software . It's very affordable with an easy enough, learning curve .

Room EQ Wizard ( REW ) (https://www.roomeqwizard.com/) may in fact be better software ( & it's free ) but seems to confound many new users .


:)

gdmoore28
12-13-2017, 02:40 PM
I really need to get the equipment and learn to measure in room I suppose. Is there software to do it that is Mac compatible? I haven’t owned a PC in 15years.

I was was hoping for a more definitive answer than “try them” :-) but I kinda figured that’s what you guys were gonna say. Haha!

i guess I need to get these all put back togeather and then give them a try. Hopefully soon.

- Woody

79326

Woody,

Are those yours in this post? Those are beautiful, and so is the room.

GeeDeeEmm

ictwoody
12-13-2017, 02:54 PM
Woody,

Are those yours in this post? Those are beautiful, and so is the room.

GeeDeeEmm

Yup. Those are snaps I took the other night. When I bought these from a guy in TX they had a Parts Express woofer, the 908-8 drivers (partially converted to 902's) and 511 horns on them along with the N-501-8B networks. I'm reworking them right now which is why they are apart. They also didn't have the damping inside the boxes as per the original plans. The build is great on the cabs. 1" china birch ply etc...

Here they were in my space when I first got them.

- Woody

79352793537935479355

gdmoore28
12-14-2017, 11:26 AM
Yes! I remember those. Must have seen and lusted over that pic a hundred times. Man, that is such a beautiful room.

GeeDeeEmm