Model 19 with 511?

[SOOTSHE]

Looking to see if anyone has used this setup. I remember when I switched my 811's for a set of 511's (same drivers) on a pair of A7's that I had, the sound was considerably more open. Is this just the way the 511 launches the sound into the listening space?

I'm pondering doing a rebuild of my 19 cabs & while I am at it, if the 511 would be an improvement I would build them to suit the 511 horn. This means that the cabinet would be slightly higher & therefore have slightly greater volume. (511 is 10 5/8" high, 811 is 8 5/8" high). Not sure if I'm going to be able to get the horn/driver combo in the same depth cabinet.....I'll need to measure that accurately. If I wish to keep the other dimensions the same, do I need to alter the port tuning at all?

Would I set the 511 back from the front of the cabinet the same as the 811 in the 19's?

So does anyone have experience from going from the 811 to the 511.....or opinions.....and will I need to alter the port tuning if I change the volume of the cabinet slightly.....or alter the set back of the horn.

Drivers will be stock 19 components....416-8B, 902's, upgraded 19 crossovers (new caps...ground lug bypass...fixed resistors for L pads).
Thanks,
John

[rontec]

.... the sound was considerably more open. Is this just the way the 511 launches the sound into the listening space?

I noticed my 511b / 808 8b's seem to have a more opened sound than my 811s. (Valencias and 19's) But it was a larger room as well. Have you tried just setting the 511's on top of the 19 cabs and running them from there for a while? Before you do any major mods!

[GM]

Basically. A bigger horn 'throws' the sound further and controls directivity to a lower F6 and why I prefer the 511 to the 811 and the 311 to the 511, etc.. The trade-off other than size is that when used with a point source driver (woofer, etc.) is that the XO point must decrease with increasing horn size for a given polar response which in turn increases its required delay. Fortunately, these are no longer the major issues they once were now that adjustable digital XO, delay systems are available.

Basic cab tuning is strictly a function net Vb, so all you need to do is increase its dims enough to account for the additional volume taken up by the larger horn/whatever.

Not having ever experimented with using a 511 with a ~1200 Hz XO, not sure how well the M19's XO will line up electrically with the horn's gain BW or if there's enough mids, HF tuning adjustment, but for sure the 511 will ideally need the same driver offset to line up acoustically for the XO's point(s) to work, making it extend in front of the woofer/cab by however much longer it is. IOW, mount it same as an 811 and you'll need a much lower XO point for best performance.

GM

[Panomaniac]

A matter of taste, I suppose. For domestic listening I much prefer the 811. It seems lighter, cleaner, clearer to me.

But I seem to be alone in this opinion.

[SOOTSHE]

Basically. A bigger horn 'throws' the sound further and controls directivity to a lower F6 and why I prefer the 511 to the 811 and the 311 to the 511, etc.. The trade-off other than size is that when used with a point source driver (woofer, etc.) is that the XO point must decrease with increasing horn size for a given polar response which in turn increases its required delay. Fortunately, these are no longer the major issues they once were now that adjustable digital XO, delay systems are available.

Basic cab tuning is strictly a function net Vb, so all you need to do is increase its dims enough to account for the additional volume taken up by the larger horn/whatever.

Not having ever experimented with using a 511 with a ~1200 Hz XO, not sure how well the M19's XO will line up electrically with the horn's gain BW or if there's enough mids, HF tuning adjustment, but for sure the 511 will ideally need the same driver offset to line up acoustically for the XO's point(s) to work, making it extend in front of the woofer/cab by however much longer it is. IOW, mount it same as an 811 and you'll need a much lower XO point for best performance.

GM

Sometimes this is hard for me to get my head around...so here goes.
I should have the 902 driver in the same position as it was with the 811 & therefore the set back from the front baffle will vary accordingly?
I may not have enough adjustment in the MF & HF L pads? So I'm assuming that the 511 will change the sound balance & I may need to adjust the L Pads?

Cabinet tuning seems fairly straightforward....just alter the volume to allow for any increases/decreases with the new horn or cabinet design...and keep the port the same.

Quote: Rontec - "I noticed my 511b / 808 8b's seem to have a more opened sound than my 811s. (Valencias and 19's) But it was a larger room as well. Have you tried just setting the 511's on top of the 19 cabs and running them from there for a while? Before you do any major mods!"

I noticed the same openness of sound when I changed from 811 to 511 on my A7's...and it wasn't just a subtle difference. I won't be modding the original cabs, I'm going to keep them in storage, as they are original. I'll build new cabs & use 1 inch ply with additional bracing. I'm keen to see if this improves the sound, so I might as well build them to suit 511's.

Quote: Panomaniac - "A matter of taste, I suppose. For domestic listening I much prefer the 811. It seems lighter, cleaner, clearer to me.

But I seem to be alone in this opinion."

Nothing wrong with that, everyone listens differently & I have to say that I love the sound of my 19's just as they are. Just can't help myself to try & see if they get any better.

Thanks for the input everyone,
John

[GM]

I should have the 902 driver in the same position as it was with the 811 & therefore the set back from the front baffle will vary accordingly?
I may not have enough adjustment in the MF & HF L pads? So I'm assuming that the 511 will change the sound balance & I may need to adjust the L Pads?

Look at this from a side section view and just to make it simple, draw a vertical line through the 902/811 flange joint and another vertical line through the 416's magnet/frame joint. The distance between these two lines represent the XO's phase delay (strictly for illustration/tape measurement purposes, the actual acoustic centers will be different), so in theory must be the same regardless of the horn used if the stock M19 XO is used. Obviously then, the longer 511 horn will protrude in front of the 416's baffle a fair amount.

If the horn is set back without lowering the XO point and/or increasing its slope order to account for its increased phase offset, there could be an audible time delay (echo) between the two.

GM

[GM]

A matter of taste, I suppose. For domestic listening I much prefer the 811. It seems lighter, cleaner, clearer to me.

But I seem to be alone in this opinion.

Different strokes, but considering the popularity of the Iconic/Valencia and especially the M19 among the Altec cognoscenti that I don't share, I'd say I'm far more the odd man out than you. I just don't like using a 15" woofer this high up for vocals. Now a 9844 is a whole different ballgame.

GM

[SOOTSHE]

GM,
Thanks for that explanation....understood.
I'm sure you have a great technical explanation of why you dislike the model 19, but when I just use my ears it's the most musical & realistic speaker that I've heard.....different strokes indeed.
Many thanks,
John

[GM]

You're welcome!

Don't know if I have any technical explanation beyond a 15" output this high up is nothing but break-up modes which is technically called distortion. Mostly though, it's about how we hear which is the same, yet not so much. Disconnect the horn and listen to music to get an exaggerated version of how I perceive the woofer's underlying 'grunge' that the HF horn doesn't completely mask for me unless XO'd lower to a larger horn.

GM

[Altec Best]

We all hear differently,and we have our likes and dislikes.I like the 811 too.More so now with the tight fitting foam around the bell of the horn that keeps the horn from resonating to the point of ringing.The 811 and the 511 for that matter need to be damped.My 511E's with a big 288 sound wonderful.I wish Altec had done the same thing with the 811's as they did with the 511E.