# Choosing an amplifier



## Snpbond (Jul 17, 2013)

I've been spending a lot of time looking around at amplifiers and would like some advice and maybe some information on some of the amplifiers CSS offers. Seeing that I'm in Saskatchewan I'd prefer ordering through CSS and they seem to have a great selection to choose from.

Basically I'm looking to build my first DIY sub with an Exodus Tempest-X 15" driver, I'm looking to build a ported enclosure tuned to 17Hz and need to choose a plate amp for it. I'm looking at a 500W amp and am having trouble choosing between the Dayton SPA500, PE BASH500, or the PA500 (which I understand is a Yung AMP).

The Dayton is an attractive option and includes an adjustable EQ with a built in HPF at about 18Hz as I understand, the downside is I've read quite recently that they are still having issues with popping/humming and that is worrying...

The BASH500 is a nice option as well though it lacks the ability to adjust the bass boost unless I specify on order. I can't find any specifics and hope maybe someone here knows, but it appears from the spec sheet on Parts Express that the built in 3db Boost is around 34Hz with a HPF of 30Hz? I've read that is an outdated document but it's hard to get any concrete info on this amp.

And finally the Yung (or PA500 as CSS has it listed), I believe this has a 20Hz HPF with an bass boost at 25hz that is adjustable (not 100% on that). I haven't looked too closely at the Yung amp yet.

I'm really just looking for some direction as to what I should choose or any clarification on the information I've gathered on these amps, a lot of it is from a few years ago and may be different now. Does anyone have any experience using any of these amps? :dontknow:


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## Mike P. (Apr 6, 2007)

Welcome, flat lander from Moose Jaw! :T

You are correct on the amps as far as I know. The Bash would be your best bet in my opinion but contact P.E. and verify the "new" amp has a HPF at 18 hz.

The Yung amp is a strange one, it apparently has a HPF at 30 hz with boost at 25 hz so it is flat to 20 hz. That came from testing the P.E. Yung amp, I'm not sure if CSS had an mods done to their version of the Yung amp. You should contact CSS and inquire.

That being said, your tuning frequency is a bit low for the HPF that you will be using. What is the net volume of your cabinet?


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## Snpbond (Jul 17, 2013)

Thanks for the reply! Great to see another Saskatchewan guy on here!

I've been modelling the box in WinISD and based my design off an Exodus Audio document I found, looking at the 300L 17Hz ported example:

http://www.bassmasters-heaven.nl/fi...dio_tempest_x_subwoofer_application_notes.pdf

I set my volume a bit larger than the 300L 17Hz example to 340L as I liked the response better in WinISD but that may be adjusted down again before I actually start my build. 

So ideally I'd like the HPF to be slightly lower than the tuning frequency correct? 

I haven't seen any plate amps that are set that low (maybe the BASH can be customized for that) and I'd like to stay away from pro-amps like the iNuke just because I like the compact design of having a plate amp.

Any suggestions are welcome though, nothing is set in stone yet


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## Mike P. (Apr 6, 2007)

Assuming you have the MK II of the driver I modeled it in 340 liters tuned to 17,18, and 19 hz. There's not much difference in output with a 18 hz HPF. What will you be using for porting?


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## Snpbond (Jul 17, 2013)

I'm waiting to hear back from Parts Express on the BASH amp specifications, for the port I'm looking at ordering this:

http://creativesound.ca/details.php?model=6FP


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## Mike P. (Apr 6, 2007)

That will tune 340 liters to 19 hz.


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## Snpbond (Jul 17, 2013)

Would you recommend 2 - 4" ports then? Other than finding some PVC and making an 8" port there doesn't seem to be any kits that size.

Parts Express replied saying the boost table document is correct:

http://www.parts-express.com/pdf/300-752.pdf

So if I understand it correct the default HPF is 30.6Hz so I would have to ask CSS to adjust that on order..


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## Mike P. (Apr 6, 2007)

Two 4" ports will work, each cut to 14" overall will tune to 18 hz. The HPF at 18.7 hz from the 1 db boost chart would be a good match for your setup.


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## Snpbond (Jul 17, 2013)

Thanks! I've ordered the BASH 500 modified with 18Hz HPF and 3db boost in 20-24Hz range an 2 - 4" flared ports from CSS.


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## Mike P. (Apr 6, 2007)

That should be 1 db of boost not 3 db. With 3 db of boost in the 20 -24 hz range your port air speed is too high.


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## Snpbond (Jul 17, 2013)

Would I be able to adjust the port length to compensate or do you think I should just have them lower it to 1 db boost? How can I calculate this value?


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## Mike P. (Apr 6, 2007)

3 db will create hump in the response, and you would need three 4" ports to deal with the air speed.


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## Snpbond (Jul 17, 2013)

Thanks for the tip! I've emailed them asking to change that modification order to the 1db boost in 25-30hz range with 18.7 HPF.


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## Mike P. (Apr 6, 2007)

If you don't mind me asking, where did you get the driver from? When I inquired about them the shipping was expensive to Canada.


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## Snpbond (Jul 17, 2013)

I've bought it off a friend, it's currently in a sono-tube...I'm not sure where he originally purchased it but he's using an 18" Mach 5 now and doesn't need this driver anymore.

I believe this is the spec sheet for it, don't believe I listed it earlier:

http://www.bassmasters-heaven.nl/fi...empest_x/exodus_audio_tempest_x_subwoofer.pdf


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