model 19 clone box for my A7 500Hz components?

[kipduff]

As explained in my other thread, I have just received components from a 1966 A7: 416-A (16 ohm), 502-D (16 ohm), 511B horn, N-500-E crossover. Want to make simple box (excluding enclosure for horn) based on the dimensions of model 19 (or whatever I can find that's appropriate) - and mount horn on top in open (like VOTT's). Obvious differences to me are:

1) 416-A will have to be rear mounted- I can determine cu. inches to add to box volumne (once determined) to compensate.
2) model 19's were tuned for 416-8B. What T-S parameters I've found so far for 416-A seem to differ from 416-8A, but box dimensions could be altered as necessary when correct T-S parameters are nailed down.
3) my system crosses over at 500Hz instead of 1000 or 1200Hz. Is a model 19 box tied to a 1200Hz crossover and smaller horn?

It's possible that because A7's have LF driver horn loading, this driver in a box with flush mounting will be over-powered by the 511B horn.

Thanks, Kip.......

[Elitopus1]

I'm not sure about cab tuning for the 416a. I'm sure someone will know the correct volume and port size for that setup.

Personally I would use a 800hz or 1200hz crossover point. The 511 horn does not sound good that low to my ears.

Plus the M19/Z19 crossovers are built with MF EQ included. It makes the horn sound much better. IMO it turns a theatre speaker into a HiFi speaker

[kipduff]

I'm not sure about cab tuning for the 416a. I'm sure someone will know the correct volume and port size for that setup.

Personally I would use a 800hz or 1200hz crossover point. The 511 horn does not sound good that low to my ears.

Plus the M19/Z19 crossovers are built with MF EQ included. It makes the horn sound much better. IMO it turns a theatre speaker into a HiFi speaker

Would use of 800 or 1200 XO require discarding the 502D/511B assembly for 802/811 horn assy?

[Elitopus1]

You can cross the 511 horn at any frequency above 500hz. That is just its lower cut off frequency.

I used to run a pair of 511b crossed over at 800hz with my 828 cabs. I used an active crossover and played around with different crossover points. I preferred 800hz with that setup. A few of the guys here use a 1200hz crossover point with various Altecs, including 828 cabs, and Valencias.

The HF driver you have is the same 802D you would use with the 811 horn. It is an 800 series driver, which has the same body as the 808. There is no 502D

[kipduff]

You can cross the 511 horn at any frequency above 500hz. That is just its lower cut off frequency.

I used to run a pair of 511b crossed over at 800hz with my 828 cabs. I used an active crossover and played around with different crossover points. I preferred 800hz with that setup. A few of the guys here use a 1200hz crossover point with various Altecs, including 828 cabs, and Valencias.

The HF driver you have is the same 802D you would use with the 811 horn. It is an 800 series driver, which has the same body as the 808. There is no 502D

Yes- I've been laboring under some misconceptions- got it in my mind somehow that the 811 and 511 horms used different drivers. And seem to have lost the ability to remember the model numbers on my own components. My apologies to thread for faulty listing of components. After a 10 hour day working on petrol tankers, brain not @ full capacity.

Well that's good news- components are usable with the adoption of a higher crossover. Your statement: "HiFi vs. theater" is informative.

I've been laboring under another significant misconception- after reviewing thread at Altec 19, post #6, I realized there is no simple box version of model 19- the housing for the 811 horn is connected to the lower box. The 8.3 cu.ft. volume quoted did seem high for just the lower box. I assumed the boxes were separate- the 19 is unusual in that way. I'm not going to consider making a model 19 for this project because it's more work than I plan at this point- and is designed for differen components. Looks like I can proceed with an Altec (or scratch built) 800Hz crossover and basic box tuned for 416A. I will research the crossovers you mentioned earlier.

[Old Guy]

843 might work

http://www.lansingheritage.org/image...ure/page11.jpg

[gdmoore28]

Kipduff,

If you are interested, I have a build currently in process that incorporates 416s, 511Bs, 802Ds, and a custom built 800Hz crossover with horn eq posted here:

Altec 606-Inspired Build Using A-7 Components | Audiokarma Home Audio Stereo Discussion Forums

I went with a corner cabinet loosely based on the Altec 606 plans, but altered them for a Model 19 look with the horn cabinet separated from the main cabinet.

My 416s are 8 ohm and my 802Ds are 16 ohm, so the crossover was built for that impedance. However, it is VERY easy to convert the crossover for whatever impedance your speakers are rated for. Be happy to help you with that, but be forewarned that I'm not a trained EE. I based my crossover on the recommendations of those who are.

GeeDeeEmm

Altec Partial Assembly 004.jpg

[GM]

2) model 19's were tuned for 416-8B. What T-S parameters I've found so far for 416-A seem to differ from 416-8A, but box dimensions could be altered as necessary when correct T-S parameters are nailed down.

3) my system crosses over at 500Hz instead of 1000 or 1200Hz. Is a model 19 box tied to a 1200Hz crossover and smaller horn?

It's possible that because A7's have LF driver horn loading, this driver in a box with flush mounting will be over-powered by the 511B horn.

OK, recommend a MLTL alignment similar to this large M19 MLTL variant using M19 components:

GM's MLTL with 416-8B

GM's MLTL with 416-8B - Google Search

I will use these T/S specs unless you get yours measured at the average power you plan to use them at, though MLTLs are tolerant of specs variance since by design they are acoustically large, so damping, possibly fine tuning the vent is all that's required:

416A specs ?? N-801-8A specs ??

Folks typically prefer the horn centerline to be at, or above, seated ear height, so need this info and if there's any width, depth limitations; I normally use 30" W, though wider is better if well away from any walls.

Correct, but your XO is designed for 500 Hz with impedance shelving to counter the difference in woofer, horn efficiency, though with today's recording's much higher HF, a bypass capacitor will be needed to create the M19's CD horn EQ.

GM

[kipduff]

Kipduff,

If you are interested, I have a build currently in process that incorporates 416s, 511Bs, 802Ds, and a custom built 800Hz crossover with horn eq posted here:

Altec 606-Inspired Build Using A-7 Components | Audiokarma Home Audio Stereo Discussion Forums

I went with a corner cabinet loosely based on the Altec 606 plans, but altered them for a Model 19 look with the horn cabinet separated from the main cabinet.

My 416s are 8 ohm and my 802Ds are 16 ohm, so the crossover was built for that impedance. However, it is VERY easy to convert the crossover for whatever impedance your speakers are rated for. Be happy to help you with that, but be forewarned that I'm not a trained EE. I based my crossover on the recommendations of those who are.

GeeDeeEmm

Altec Partial Assembly 004.jpg

Awesome- I,m at work, but will contact you when I get home on real computer. Interested in all that......

[kipduff]

OK, recommend a MLTL alignment similar to this large M19 MLTL variant using M19 components:

GM's MLTL with 416-8B

GM's MLTL with 416-8B - Google Search

I will use these T/S specs unless you get yours measured at the average power you plan to use them at, though MLTLs are tolerant of specs variance since by design they are acoustically large, so damping, possibly fine tuning the vent is all that's required:

416A specs ?? N-801-8A specs ??

Folks typically prefer the horn centerline to be at, or above, seated ear height, so need this info and if there's any width, depth limitations; I normally use 30" W, though wider is better if well away from any walls.

Correct, but your XO is designed for 500 Hz with impedance shelving to counter the difference in woofer, horn efficiency, though with today's recording's much higher HF, a bypass capacitor will be needed to create the M19's CD horn EQ.

GM

I'm honored by your response. Really like the look of it- I also like the light baltic birch look- but went to "upgrade your account" on PhotoBucket: $399... It will take me a while to grind thru all the info in that post- I still work full-time and OT- to bed soon for 3:30 am alarm. My room is small- speakers of this size too big I think at this point. Thinking 612 cab size.... 6 - 9 cu.ft. (think I'm gonna do 612 for my 604-8H's) As far as height/ear level, I use heavy cinder blocks- and I have found some great industrial dense, sticky 1/2" rubber sheet to stabilize floor-to-block and block-to-cab interfaces. Floor is linoleum on concrete with some throw rugs around. I listen pretty loud.....

Here are specs I found on line for 416A (16 ohm)- I have never heard of Bl or Le. They don't seem that credible to me- but I'm not qualified to be sure. I have not found any specs yet for the N-500-E XO. I will be researching more after work tomorrow.....

Xmax: 0.6"
Xmax: 15mm
Re: 12.54 ohms
Fs: 21.4
Vas: 36.8 cu ft
Qts: 0.272
Le: 2.5
Bl: 18.01
cone dia: 12.7
Cms: 0.001124