M19s vs A7x

[Phil-G]

The M19 has way more bass and much more tonally balanced than an 816 since it's unloaded below ~156 Hz. What it has is chest pounding upper mid-bass, lower mids ~ the same as an A7 that allows for much greater efficiency from ~200 Hz all the way up to the HF horn's limits, so as already noted, it seems like a kick-a$$ sub system is the preferred route here.

That, or make a reasonable compromise same as me, AB and some others have done by using dual woofers in large cabs that at least in my case is better overall performing than when they were ~70 Hz compression horn loaded. In room, ~corner loaded, my ~20 ft^3/16 Hz Fb cabs are at least 103 dB/4ft eff. down to around 20 Hz.

GM

so i guess i'll be following suite and build a double too. after i give up trying to tune my A7s down below 70.

[bowtie427ss]

so i guess i'll be following suite and build a double too. after i give up trying to tune my A7s down below 70.

Forget the horns in the foreground, behind them is my A7 LFE solution in conjunction with a DCX2496 and a few hundred solid state watts.

[GM]

Yeah, that's the ticket! My current mains were originally the subs and platforms for the big horns.

GM

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Without the enclosures they are just that, components.

Thanks Again GM !!! If I had one wish I only wish that you could hear them.

True, but the cab alignment is only as good as the driver's electro-mechanical specs allow it to be.

Thanks for the 'attaboy', but all I've done is learn from the pioneering EEs and MEs that worked it all out mathematically before even my dad was born, then fine tuned it with real world measurements. I've added nothing to the core knowledge base and lack the creativity of a Tom Danley to take my knowledge to the next level without first being shown the way.

That said, in some ways I 'see' the way things are acoustically to make what I consider overall superior designs Vs what the math smart guys conclude because they rely too heavily on T/S and 1D wave equations, which 'boxes in' cab alignment options.

Well, my game plan is to do some traveling to [hopefully] enjoy some of my hard won savings before the gov't. steals it for redistribution if/once I can complete this ~ 1 yr whole property rehab that's been dragging on for almost 5 yrs now; so who knows, I haven't been to Atlantic City since '85 IIRC and you're along the way, right?

GM

[Altec Best]

Forget the horns in the foreground, behind them is my A7 LFE solution in conjunction with a DCX2496 and a few hundred solid state watts.

I like Tom ! That's what I'm talking about !

True, but the cab alignment is only as good as the driver's electro-mechanical specs allow it to be.

Thanks for the 'attaboy', but all I've done is learn from the pioneering EEs and MEs that worked it all out mathematically before even my dad was born, then fine tuned it with real world measurements. I've added nothing to the core knowledge base and lack the creativity of a Tom Danley to take my knowledge to the next level without first being shown the way.

That said, in some ways I 'see' the way things are acoustically to make what I consider overall superior designs Vs what the math smart guys conclude because they rely too heavily on T/S and 1D wave equations, which 'boxes in' cab alignment options.

Well, my game plan is to do some traveling to [hopefully] enjoy some of my hard won savings before the gov't. steals it for redistribution if/once I can complete this ~ 1 yr whole property rehab that's been dragging on for almost 5 yrs now; so who knows, I haven't been to Atlantic City since '85 IIRC and you're along the way, right?

GM

What I'm mostly talking about is your helping me with the design.And for that matter countless other folk's for decades ! For me personally it means a lot. I appreciate your time ! Sounds Great ! My wife and I were thinking of taking a road trip too.South to Florida,sometime in September or early October..I'm north of AC about 75 miles northeast of AC. I'm in central NJ on the Pennsy/New Jersey border.Mercer County.About 10-15 minutes from Princeton.

Sounds good.If you can make it we'll have to plan the day maybe take a ride up to NYC or AC..After a nice listening session..

I still have to finish the veneer with stain and poly.And I'm still playing with the HF drivers/horns trying to get the best match.

[Alien_Shore]

The M19 has way more bass and much more tonally balanced than an 816 since it's unloaded below ~156 Hz. What it has is chest pounding upper mid-bass, lower mids ~ the same as an A7 that allows for much greater efficiency from ~200 Hz all the way up to the HF horn's limits, so as already noted, it seems like a kick-a$$ sub system is the preferred route here.

That, or make a reasonable compromise same as me, AB and some others have done by using dual woofers in large cabs that at least in my case is better overall performing than when they were ~70 Hz compression horn loaded. In room, ~corner loaded, my ~20 ft^3/16 Hz Fb cabs are at least 103 dB/4ft eff. down to around 20 Hz.

GM

Greg, as is usually the case, it takes me about 4 times reading your posts, (and then me standing on a foot stool) before I get it. It is that expansive mid bass range that sound so good to my ear. I don't get that with my M14s upstairs. So I will play around with a sub + my 816s. Building a powered sub-woofer will be a fun project. Now to decide stereo vs mono subs...

[analog addict]

Not to belabor the point, but the looking around I did when I got my first pair of 816s suggested that the idea of stacking 816s or other similar horn cabinets allowed for lower bass extension through some sort of "sonic linking". The more you stacked, the lower they'd go. Can anyone elaborate further on this principle?

[Earl K]

Not to belabor the point, but the looking around I did when I got my first pair of 816s suggested that the idea of stacking 816s or other similar horn cabinets allowed for lower bass extension through some sort of "sonic linking". The more you stacked, the lower they'd go. Can anyone elaborate further on this principle?

Put somewhat crudely, when using multiples of 816s , the mouth area of the horn is increased enough ( an important factor in horn loading ) that the transition from horn loaded response to bass reflex is lowered by a portion of an octave .

See the following comparison of the 816 vs the 817 ( as a reasonable demonstration of the effect ) ;

[Altec Best]

Not to belabor the point, but the looking around I did when I got my first pair of 816s suggested that the idea of stacking 816s or other similar horn cabinets allowed for lower bass extension through some sort of "sonic linking". The more you stacked, the lower they'd go. Can anyone elaborate further on this principle?

Alan scroll down to "Multiple Subwoofers" this should give you a better understanding.. Actually the whole post by Big Daddy "The Science Behind Subwoofer Placement" is interesting with lots of good info..

A Guide to Subwoofers (Part II): Standing Waves & Room Modes - Blu-ray Forum

Here's part 1 if you would like to read that as well.

"A Guide To Subwoofers" http://forum.blu-ray.com/showthread.php?t=43669

Bill Fitzmaurice is a friend of mine.He frequents the Tech Talk forum quite a bit.He did this post on his website that illustrates Stacking & Placement of Subs..

http://billfitzmaurice.info/forum/viewtopic.php?t=398

[GM]

the mouth area of the horn is increased enough ( an important factor in horn loading ) that the transition from horn loaded response to bass reflex is lowered by a portion of an octave .

Right, ~ a half octave with a doubling of horns, so four square or two square on a concrete or similar floor for an octave.

GM