A 2245 for no reason at all....

[mark214]

While browsing a local music shop who is no longer a JBL pro dealer I spotted a 2245 in the back with a completely rotted surround, they said $20 and get it outta' here. It is big, JBL and cheap so I bought it.

Ordered a surround kit with dust coves and completed it last night, tried it free air today. No rub everything seems to be centered and it as far as a free air check out goes sounds good, the bead of glue I drew on the dust cover with the plastic bottle leaves a bit to be desired.

It is big, JBL, cheap, now works and I don't know what the heck I will end up doing with it..

[hjames]

Wow wow - cool beans on that deal!

Now you need a big ol' box and a sub amp to make the most of it!

While browsing a local music shop who is no longer a JBL pro dealer I spotted a 2245 in the back with a completely rotted surround, they said $20 and get it outta' here. It is big, JBL and cheap so I bought it.

Ordered a surround kit with dust coves and completed it last night, tried it free air today. No rub everything seems to be centered and it as far as a free air check out goes sounds good, the bead of glue I drew on the dust cover with the plastic bottle leaves a bit to be desired.

It is big, JBL, cheap, now works and I don't know what the heck I will end up doing with it..

[Don Mascali]

http://www.lansingheritage.org/html/.../1983-subs.htm

I would build the big one.

[mark214]

I have one of these that I built years ago and I am in the process of recapping.

Wow wow - cool beans on that deal!

Now you need a big ol' box and a sub amp to make the most of it!

[Eaulive]

I have one of these that I built years ago and I am in the process of recapping.

Not powerful enough, and those old unprotected amps have the nasty habit of outputting DC when they screw up, you don't want to toast your new toy .
You need good damping for subwoofer applications, look for a newer amp.

[hjames]

I have one of these that I built years ago and I am in the process of recapping.

Yeah, we had them back in the 70s at a campus radio station I worked at ... SouthWestTechProductsCorp

90 watts is not enough juice ...
I've got an old Hk Citation amp i use that puts out a claimed 600watts in bridged mono mode
and i use that to feed a 2235 (15 inch) woofer, and some folks use a LOT more for an 18!!

[mark214]

Ya, the Tiger has more sentimental value than useful value being one of my first kits.

I have a MBI-400 kit which I can use to bridge a stereo 400 into 600 watts mono.


Always another project

[hjames]

Ya, the Tiger has more sentimental value than useful value being one of my first kits.

I have a MBI-400 kit which I can use to bridge a stereo 400 into 600 watts mono.


Always another project

Right - if you want to bridge an old Dynaco, go for it!
Not sure what the damping factor would be for that,
or how well it would handle an 18 inch sub, but do let us know what happens ...

Ah, ok - this website has some specs ...

http://home.indy.net/~gregdunn/dynaco/components/ST400/index.html


Damping Factor:

Greater than 80 to 1 KHz into 8 ohms;
Greater than 30 to 10 KHz into 8 ohms.

[loach71]

Right - if you want to bridge an old Dynaco, go for it!
Not sure what the damping factor would be for that,
or how well it would handle an 18 inch sub, but do let us know what happens ...

Ah, ok - this website has some specs ...

http://home.indy.net/~gregdunn/dynaco/components/ST400/index.html


Damping Factor:

Greater than 80 to 1 KHz into 8 ohms;
Greater than 30 to 10 KHz into 8 ohms.

I would suggest any DYNA 400 user visit the Audio by Van Alstine website.

http://www.avahifi.com

Frank Van Alstine is a recognized genius at the refurbish / redesign of the old DYNA amps. Drop him a note about upgrading your DYNA ST400...

[BMWCCA]

Right - if you want to bridge an old Dynaco, go for it!
Not sure what the damping factor would be for that,
or how well it would handle an 18 inch sub, but do let us know what happens ...

Damping Factor:
Greater than 80 to 1 KHz into 8 ohms;
Greater than 30 to 10 KHz into 8 ohms.

Damping Factor must be one of those statistics that mean nothing from manufacturer to manufacturer. Sort of like tire treadwear numbers.

My DC 300A-II used with my 4345s is rated this way by Crown:
Damping Factor: Greater than 750 from DC to 400 Hz

Looks like at least 400 at 1KHz.

[mark214]

I would suggest any DYNA 400 user visit the Audio by Van Alstine website.

http://www.avahifi.com

Frank Van Alstine is a recognized genius at the refurbish / redesign of the old DYNA amps. Drop him a note about upgrading your DYNA ST400...

I talked with Frank three times on the phone when he rebuilt one of my 400's. No doubt he knows more than most but my gosh what a crotchety guy with a chip on his shoulder with Dynaco "stealing" his double ST400 design for the 416. He was crotchety in the 80's I can only imagine how he is now.

[loach71]

I talked with Frank three times on the phone when he rebuilt one of my 400's. No doubt he knows more than most but my gosh what a crotchety guy with a chip on his shoulder with Dynaco "stealing" his double ST400 design for the 416. He was crotchety in the 80's I can only imagine how he is now.

Don't even dare to mention the name of James Bongiorno (reputed designer of the ST400) with Frank... Notwithstanding his grumpiness, Frank is one of the old jewels of analog audio. He is a wellspring of engineering expertise.

[lgvenable]

drive it with 600 wpc, set your gain accordingly; find a good AB Systems amp; they're theater amps and drive a 2245 to infrasonic output:
heres my 2245 sub:
http://www.audioheritage.org/vbullet...ht=#post306016

thats a AB Systems 821 bridged to 600 WPC siting on top.

[Don Mascali]

drive it with 600 wpc, set your gain accordingly; find a good AB Systems amp; they're theater amps and drive a 2245 to infrasonic output:
heres my 2245 sub:
http://www.audioheritage.org/vbullet...ht=#post306016

Now that is a sub after my heart. Too much is just right.

[dr_gallup]

http://www.lansingheritage.org/html/.../1983-subs.htm

I would build the big one.

That article in Audio inspired me to build a 12 cu ft 2245 sub back in 1983. I used to use it with a bridged Carver M400, 600 watts. Along with a Carver M1.5T main amp the lights would dim on the Telarc 1812 canon blasts. I've recently replaced the 2245 driver. Still using the Carver M400 but no longer bridged. I don't need that much power and gain anymore. The rest of my HT 7.1 system is not as efficient and only has 135 W/channel. The M1.5T was retired when I got tired of repairing it after the 4th or 5th time.