Big Solid State Amps

[luvdunhill]

So, I'm working on a pair of monoblocks. swt61 has seen these monster heat sinks. 12.2" wide x 12" tall with 2.925" fins and 0.326" base, weight is 13 pounds... and I got four. I've done some thermal plots of 6 devices per heatsink on a small PCB. Each device is dissipating 14.8W x 6 devices x 4 channels ~ 350W. I'm wondering how much further I can push the devices. The sim data is very close to actual temperatures and since I don't want to drill holes under the devices for thermal probes, the simulator will be gospel. I don't really want to move the devices apart anymore, as I have a PCB in mind I'd like to accommodate, plus a design of my own.

Datasheets for devices:

http://www.fairchildsemi.com/ds/FQ%2FFQA12P20.pdf

http://www.fairchildsemi.com/ds/FQ%2FFQA19N20C.pdf

Attached are some plots and below is the tabular sim data:

Thermal Design Details

Heatsink type:	Extrusion

Part number:	Extrusion: 9012

Weight:	5.26685 kg

Heatsink dimensions:	309.96 mm wide x 304.8 mm long x 74.3 mm high

Material:	Aluminum

Finish:	B





Environment

Ambient Temperature:	25.0 C

Altitude:	0.0 m





Thermal Design Details

	Temperature

Source Names 	%sc 	Power 	Tsink-avg 	Tsink-max 	Tcase 	Tjunction

			C 	C 	C 	C

N2 	0.3% 	14.8 W 	49.5 	49.6 	49.6 	77.9

N1 	0.3% 	14.8 W 	48.6 	48.9 	48.9 	74.4

N3 	0.3% 	14.8 W 	49.1 	49.3 	49.3 	75.5

P2 	0.3% 	14.8 W 	49.5 	49.6 	49.6 	75.9

P1 	0.3% 	14.8 W 	48.6 	48.9 	48.9 	72.3

P3 	0.3% 	14.8 W 	49.1 	49.2 	49.2 	75.5

[Icarium]

Sweet I'm sure this will be awesome.

[n_maher]

Are you sure you want to push them any harder? I mean seriously, how much of a space heater are you trying to create?

[guzziguy]

These will be TWAs. Texas Winter Amps.

[swt61]

I'll be making solid wood face panels for these big boys.

Maple with Pink Ivory heart shaped inlays. Marc did you want little Purple Heart daisy inlays as well? No extra charge.

[luvdunhill]

just bought some metal online. If anyone needs to buy from onlinemetals.com, let me know and I can send you a discount coupon as part of their refer a friend. It's an additional 5% off, which is added to their 5% discount for signing up and the 10% discount for material orders over $100.

Anyways, here's what I got:

Aluminum 6061-T6 Bare

Extruded Square

0.375"

Cut to: 11.8425"

8 @ $1.66

Aluminum 3003-H14

Perforated Sheet Round Hole

0.125" Thick

(0.5" dia. holes)

0.6875" stagger

Cut to: 12.0457" x 5"

4 @ $10.84

Aluminum 6061-T6 Bare

Extruded Rectangle

0.375" x 2"

Cut to: 4.25"

4 @ $2.55

Plastic Teflon Virgin NATURAL

Extruded Round

0.8125"

Cut to: 12"

1 @ $9.03

Plastic Acetal Black

Round

1.375"

Cut to: 12"

1 @ $9.29

[luvdunhill]

oh, and before you ask what the last two items are for....

[JBLoudG20]

Plastic Teflon Virgin NATURAL

1 @ $9.03

You dog.

[swt61]

Building your own sex toy belongs on another forum!

[JBLoudG20]

Building your own sex toy belongs on another forum!

Aerius' forum.

[Sherwood]

Which parts of the plastic virgin are teflon and which parts are natural?

At least she'll be warm

[luvdunhill]

Which parts of the plastic virgin are teflon and which parts are natural?

At least she'll be warm

as long as the black Delrin rod doesn't get involved.

[swt61]

Cue Aerius, cue Aerius.

[grawk]

cuckold jokes hit too close to home for aerius.

[luvdunhill]

so, does anyone need anything anodized black? I found a place to do it locally, but requires a minimum order of $100...

[Pars]

so, does anyone need anything anodized black? I found a place to do it locally, but requires a minimum order of $100...

Oooh... could in the future, but not right now.

[luvdunhill]

this is the general idea... the heat sinks totally dwarf that big Plitron

[guzziguy]

Ah yes, the ghetto Halcro look. Very nice!

[Dusty Chalk]

so, does anyone need anything anodized black? I found a place to do it locally, but requires a minimum order of $100...

Yes.

[guzziguy]

Yes.

So you're the one that bought the chrome plated PS-1s.

[Dusty Chalk]

No, I just want something -- possibly several somethings -- anodized black.

[JBLoudG20]

No, I just want something -- possibly several somethings -- anodized black.

It would probably be a bad idea to anodize your penis. Just thought you might like to know.

[n_maher]

this is the general idea... the heat sinks totally dwarf that big Plitron

Heatsinks look undersized to me.

[asebastian0]

Those are some manly heatsinks! Curious as to what type of topology you are using for this amp... I have a ton of these devices and no set design yet. If you still have a referral to onlinemetals I could definitely use one for an upcoming copper sheet purchase.

[swt61]

Heatsinks look undersized to me.

Yeah and John Holmes had a small pee pee.