Home theater amplifers

[Lee Batchelor]

Hi everyone,

I've been away for a long time, but I'm back with a question or two.

I built my home theater about 12 years ago. The room is 22' by 35'. I use two Altec Lansing Valencia cabinets (circa 1974: A7-800 kits in mint condition with new HF domes by Great Plains Audio), a custom designed center channel speaker and an Eminence Lab 12 sub; the latter two designed and built by yours truly. There are two rear channel speakers as well.

At the time, the recommendation was to select Small for both Left and Right channels (regardless of whether you had large 15 inch cabinets) while a decent sub would do all the heavy lifting. I assume the Large setting was for those who didn't own a sub. I have never agreed with that setting for my theater. At the time, the manufactures seemed to cater to those who wanted a "kit" or for people who had to buy small bookshelf style speakers and a small sub for their 8' by 9' home theaters. That's fine but what about those who have large systems and a large room??

Now my question: has the industry finally woke up to cater to those who use large speakers? Are there amps available that pump out decent front speaker bass WITHOUT shutting down bass redirection to the sub? Why can't we have both? My current amp is a 12 year old Denon. When I select Large, the sub is basically useless. When I select Small, I may as well sell the Altec speakers on eBay and visit my local big box store for a pair of 3 inch woofers. Can you tell I've been away for a while? I really don't know what's available!
Thanks folks...

- Lee

 

[lovinthehd]

What's the question? What's wrong with the Denon you're using?

Bass management still works the same. There are some avrs with double bass features for use with speakers set to large (does your Denon have LFE + main?). If your speakers truly have the bass response you need that's great, just depends on how low and how loud your speakers can go. I prefer subs and bass management personally.

Curious, what's the sensitivity of your current speakers? You could just add some power amps if you want more, does your avr have pre-outs?

 

[TLS Guy]

What's the question? What's wrong with the Denon you're using?

Bass management still works the same. There are some avrs with double bass features for use with speakers set to large (does your Denon have LFE + main?). If your speakers truly have the bass response you need that's great, just depends on how low and how loud your speakers can go. I prefer subs and bass management personally.

Curious, what's the sensitivity of your current speakers? You could just add some power amps if you want more, does your avr have pre-outs?

The sensitivity is 97.5 db 1 watt 1 meter. A 10 to 15 watt amp will drive these speakers to deafening levels. These are the speakers. They are form the 70s and were a consumer speaker using the Altec Voice of the theater components, that were widely used in cinemas across the world.

They used 15" drivers and crossed to the compression driver loaded by large sectoral horns at 800 Hz.

If memory serves me correctly the f3 was in the low forties. The drivers were low Q types and the bass very punchy, with very articulate dialog.

So the OP has a highly authentic "70s West Coast Sound."

In a speaker like this they absolutely should be run full range and not crossed over, just supplemented with a sub. Doing anything else will totally destroy the character and shear effect of these speakers.

Ideally all speakers should be set to large. However most are in some way incapable and have to be set to small, and in most cases this means a sub optimal crossover.

The longer I do this the more I'm convinced that speakers should be either truly full range or designed with an integrated bass/sub system. Failing that just gently supplementing the last octave with a sub also work well. The worst option and the one these days almost universally required because of the preponderance of incapable speakers, is to set the speakers to small with a full two way crossover.

I know exactly what this guy is complaining about. If his receiver can not be set to send full range to the main speakers and add in the subs around 60 Hz, then he needs to get one that can.

 

[Mark of Cenla]

My Yamaha and Pioneer AVR's both have the option to set the fronts to "large" and use the sub at the same time. The Yamaha is three years old, and the Pioneer is two years old; both were bottom of the line. I only use subs in the living room. Once when I was watching a sci-fi movie with really heavy bass (the fronts were set to "large" and the subs were on), there was some type of interaction between them, and they were both visibly moving, almost flapping. Now I always set the front speakers to "small" or turn off the subs. Peace and goodwill.

 

[BoredSysAdmin]

Ideally all speakers should be set to large. However VAST MAJORITY are in some way incapable and have to be set to small, and in most cases this means a sub optimal crossover.

minor edits and highlights.

 

[Lee Batchelor]

Thanks everyone for chiming in!

TLS - those pictures represent my exact speakers. My home made cabs are identical. I have the plans right from Altec. (Back in 1974 when I bought the parts, my dad was an Altec dealer. I had all the parts delivered to our home just outside Toronto for $417.00 (Canadian) tax in!)

LovintheHD - my Denon has an LFE + main selection. I used it in the past but didn't notice any great advantage. Based on everyone's comments, I suspect I had my sub crossed too high (90 Hz). Sounds like I should try the LFE + main setting and cross the sub around 60 Hz. I have never known the true F3 of these cabs. TLS says it's in the low 40s. I'll give this a try today and post back.

I remember listening to the Valencias in my dads store show room back in 1974. They were driven with an ordinary stereo amp. They sounded amazing and yes, very punchy. I have run them recently with a powered mixer in stereo, and they still sound the same, so it's up to me to get the mix correct with my Denon.

Thanks again....Lee