A7 and Cold Feet

[mah]

In a few weeks time I will be ready to assemble my A7-500 project from ready-cut panels. For various reasons I have wondered if a BR enclosure using the whole volume of the A7 enclosure, about 16 cu. ft., may be a simpler but still satisfactory alternative, overall?

Comments welcome.

[Steve Mac]

In a few weeks time I will be ready to assemble my A7-500 project from ready-cut panels. For various reasons I have wondered if a BR enclosure using the whole volume of the A7 enclosure, about 16 cu. ft., may be a simpler but still satisfactory alternative, overall?

Comments welcome.

You'll lose dynamics and efficiency in the mid bass if you do.
If you are using the stock crossovers then that'll be a problem too.
Bass reflex... If you wanted smaller cabs then...yeah go the model 19 approach.
If the 15s are 515s...then that's another reason to stick with the altec design.
The 515 is best in a horn type enclosure. The A7-500 is a great design...and when yer
done if there's not enough sub bass...then you will build a large horn sub woofer.

[Audio_by_Goodwill]

In a few weeks time I will be ready to assemble my A7-500 project from ready-cut panels. For various reasons I have wondered if a BR enclosure using the whole volume of the A7 enclosure, about 16 cu. ft., may be a simpler but still satisfactory alternative, overall?

Ready cut panels? Are you paying to have some cut for you? I don't see any reason to build anything else if you won't have to cut anything. Furthermore, I'd guess that a box that big, that is all reflex enclosure, wouldn't be ideal, since a lot of people reduce the volume a bit by closing off the space behind the horn flairs, if it isn't done already.

[mah]

The panels are cut to what I would call overall size. Any angled cuts still have to be done - probably routered. Also all of the horn panels have to be cut/shaped. I am using 416Bs.

If a BR of equivalent size would still give a very good result I could save myself a lot of work.

[notloudenough]

Marshall,
Is the "putting it all together" part what's scaring you ? You have people from all around the world that will be willing not only to help, you but to see your results so they can do it too.
Furthermore, you will have a set of cabinets that you will have for the rest of your life, you'll hear sounds that you've never heard before on recordings you've listened to a hundred times, and if you can get the wife to help, it will be something that you can do together with excellent results.

Keith

[mah]

Keith,

I am on the home run building a guitar tube-amp head and cabinet for my daughter. It has taken much longer than I anticipated and has pushed the Altec project way behind schedule. I guess I am just feeling a bit wary about taking on another not so straight-forward job that may take too long to complete. Probably suffering from DIY poop-out.

[GM]

Been there, done that except made them taller to get ~20 ft^3 cabs tuned to Fs to replace A7s with no regrets, so IMO the empty 825/828's ~15 ft^3 gross Vb tuned to ~24 - 32 Hz depending on amp and room/position variables will have all the dynamics required for all but possibly the largest pipe organ symphonies in a HIFI app and do it at audibly lower overall distortion than if expo horn/BR loaded.

If the budget allows, you can match the A7's overall dynamics (and then some) by adding a second 416B/channel and doubling available power and possibly with a lower tuning or even sealed up depending on the room/position variables. This is what I later did except swapped to dual 515Bs.



GM

[mah]

HI, GM,

Thanks for your reply. Can I PM you about this topic?

Regards, Marshall.

[GM]

Greets!

You're welcome!

Sure.

GM

[RonSSS]

Been there, done that except made them taller to get ~20 ft^3 cabs tuned to Fs to replace A7s with no regrets, so IMO the empty 825/828's ~15 ft^3 gross Vb tuned to ~24 - 32 Hz depending on amp and room/position variables will have all the dynamics required for all but possibly the largest pipe organ symphonies in a HIFI app and do it at audibly lower overall distortion than if expo horn/BR loaded.

If the budget allows, you can match the A7's overall dynamics (and then some) by adding a second 416B/channel and doubling available power and possibly with a lower tuning or even sealed up depending on the room/position variables. This is what I later did except swapped to dual 515Bs.



GM

Is this you in the pic GM? Maybe we all ought to post pics of our setups with us in the photo. Would make this a bit more personal.
BTW....I have the gray goatee "old dog" look going on as well. Cause I'm old!

Ron