Hi All.
Earl K made this Valencia with a 411 and a 288 driver and an 511 horn.
http://www.hostboard.com/forums/hbmc.../2013/01/8.jpg
I like the looks. BEEFY LOOK
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Hi All.
Earl K made this Valencia with a 411 and a 288 driver and an 511 horn.
http://www.hostboard.com/forums/hbmc.../2013/01/8.jpg
I like the looks. BEEFY LOOK
Nope !Quote:
Originally Posted by LICORNE
That's not mine , but I certainly like the visual presentation quite a lot ( ie; "I wish it were mine" ) .
Thanks for the image ( it's a nice "beefy" look ) !
:)
Me too, though it appears to be a 9846 box/woofer setup except with the 9848's horn, but the driver offset won't allow either's XO to work properly, so hopefully it's a hybrid also.
GM
So perhaps bi-amp and use an active crossover that does phase-alignment adjustments?Quote:
Originally Posted by GM
That would be my choice.
GM
I too am a firm believer in custom networks ( especially when components have been changed ) .Quote:
Originally Posted by GM
Let's keep in mind Licorne thought this box was mine ( & to boot, called it a custom-built Valencia ). I think the whole 288 driver ( swap thing ) is best treated as a theoretical exercise .
Having said that ( is the 511E horn swap a deal breaker for this class of network) ?
- A 288-8K on a 511E horn ( vs the 802D on a 511b ) doesn't miss duplicating the dimensional marks by all that much .
- In fact, the difference is around .75" ( with the 288-8K/511E combo coming up the "shorter" of the 2 combos ) .
- Here's bfish(s) work ( for a quick visual reference ) ;
http://www.hostboard.com/forums/hbmc.../2013/01/9.jpg
- The 288-8K is @ 4" deep from exit to ( middle of ) top plate while the 802D is @ 2.5" .
- Cutting off say 2.5" from the 511b ( then adding back on a 1/4" deep mounting flange ) leaves one with a 2.25" ( shorter horn ) with 1.5" added back ( accounting for the 288s extra depth ) giving an approx. depth difference of just .75" ( less ) .
- At crossover ( & say it's exactly 500hz ) a quarter wavelength is @ 6.5" - 6.75" . So the .75" difference is well within what I'll call an allowable zone of additive quadrature ( all the while making some pretty broad assumptions, such as Altec having actually "nailed" the phasing of the original crossover ) .
- Assuming my early morning math hasn't failed me [ ( .75 / ( 1130 / 500 * 12 ) ) * 360 = 9.96 deg ] , that .75" represents about a 10deg difference ( in phase rotation ) compared to the original network.
- A 10deg difference ( compared to the original ) wouldn't hinder the goal of achieving proper summing ( within the crossover region ) .
- OTOH, the 288 & the 802 variants differ quite a bit in their sensitivities , their impedance curves ( from 400 to 2K ) as well as their frequency response curves .
- ( If this was my project ) I would proceed to modify the original HF leg of the network based on those factors . And since I really prefer bi-amped woofers ( with passively crossed HF driven by another amp ) the original network would be right out the window .
:)
Quote:
Originally Posted by LICORNE
Looks like a stock 9846 from the outside and it should answer the question
"Where's the beef?" quite soundly........I know mine does..........
9846216 | Flickr - Photo Sharing!
Hi All
The speakers pictured are mine - they are standard 9846As
They take up a lot of real estate in our lounge! but fit snugly in the corners on 200mm stands - essentially to get clean bass.
They are bi-amped with a Marchand crossover
I love'em.
Here's the link from the previous owner
Altec 9846
Wow--those are real beauties Art! Never seen them with wood grain like that....Quote:
Originally Posted by Art J.
http://altecpro.com/pdfs/vintage/Spe...r%20System.pdf
Quote:
Originally Posted by voice of the theater
Thanks VOT. When they were new, they were sent to a cabinet maker for the stands
and finish to match the auditorium stage they were displayed on.............
Cool looking speakers, I have been looking for a pair 9846 8-a's, would love to find a pair.. they dont seem to come up for sale that often, I wonder how they sound.. A single came up locally on ebay that was restored. It appeared there was a plug that went into the crossover? Is this normal?
"It appeared there was a plug that went into the crossover? Is this normal? "
It might have been the "B" model with the phono plug input.
http://www.lansingheritage.org/image...-8b/page04.jpg
The 9846 was a commercial speaker that could be ordered different ways
depending on the application, like the B model bi-amp with the 21597 element
for studio use, all the way down to the Church A model with a symbiotic element for old church ladies.
Be careful of what's inside when buying.
"How do they sound?" Well, I have mine sounding really great but they were difficult to get right
because of the efficiency and characteristic differences between the horn and woofer.
If they aren't right, they sound muddy like 70's consumer speakers.
This speaker really needs the bi-amp route more than any other Altec as Rod Elliott explains so well.
Active Vs. Passive Crossovers
Right ! That is were the Altec 30904/30923 attenuator equalizer networks comes in... Did you use one with this application Art ?Quote:
Originally Posted by Art J.
Remember this one ? :biggrin2:
http://www.hostboard.com/forums/hbmc...2012/06/21.jpg
Hi John,Quote:
Originally Posted by Altec Best
Yes, my terrible photoshop work, but I notice it gets used a lot. I'm glad.
I used the attenuator with the bi-amp setup and its working well.
I used a better capacitor but I forgot what it was.
Some day I want to bias 2- 12uf capacitors with a 9v battery (charge couple) as I saw
over at the LH board to see if I get better top end.
I can't hear anyways but it might show on the scope..........
Yes it does get used a lot.. It works well ! Thanks for your efforts on it..Quote:
Originally Posted by Art J.
Thanks ArtJ. and AB you are a font..Quote:
Originally Posted by Art J.