Help with replacing plate amp on ported subwoofer

[AlexF40]

Hi,

I had a ported 12" sub which the amp board has blown, I was thinking about just replacing the whole plate amp rather than trying to fix the board but then started thinking about the ports.

Will this sound awful if I just replace the amp with say a Yung 300 or do I really need a DSP and if so how would I tune the DSP to the sub?

Thanks in advance.

[Paul O]

Changing the amp should not affect the sound of the sub... that is determined by the box, its tuning, and the driver with reflex designs. There can sometimes be some response shaping or protection built into the amp module but that is more of a highend or high performance type of thing, if the module you are taking out is just a basic analog amplifier that probably isn't the case.

[AlexF40]

Thanks Paul, I'm just assuming due to the size of it that it's been EZ optimised for the ports. Looks quite big just to be an amp module.

[Paul O]

That is old school for sure and it's big because of the linear power supply and toroid transformer, modern class D plate amps use switching power supplies so the whole thing can fit on a single board.

[AlexF40]

Thanks for your help Paul O I've got a lot to learn. In that case do you think it's safe to do a direct replacement then without affecting the sound?

[Steve Lee]

In my several (20+) years experience with plate sub-woofer amps is that you rent them, you do not own them as they all blow-up and die for no apparent reason here in my local.

I replaced 3 of them in a Dayton 12" sub-woofer over a 2 year period and they were hardly ever used - just sat idle and never pushed very hard when employed.

I finally just wound up installing a crown 2 channel commercial amp in a closet and wired it to the sub (s) I added a second one - a 10" in the other corner of the room.

It has been functioning flawlessly while powered-up 7 X 24 X 365 for the past 3 years and sounds much cleaner than the original Dayton/BASH/YUNG amps that blew up.

Just a thought.

YMMV.

[AlexF40]

Hi Steve, that's a good point and has just swayed me away from the Yung amps as they only have a one year warranty, the Dayton's have five. I had a look a the Crown amps and they don't appear to have line level on, plus the additional price of them, makes me still prefer the plate amp for a single sub.

[Steve Lee]

Try this my friend --> https://www.parts-express.com/crown-...ohms--245-5126

Best bang for the buck.


The unused output can be turned-down to zero output if you don't need it right now.

[AlexF40]

I'm not in the US so have 240v, it's a shame they're not switchable. But I suppose this is how they control their pricing, as the same amp over here is more than 2x the price.

[tomzarbo]

To Steve's point... placing a piece of electronic equipment in a subwoofer cabinet essentially as one of it's walls and being subject to all the vibrations and pressure changes therewith is kind of asking for it to fail over time. I'm pretty sure that's why we hear about so many subwoofer plate amps failing after a few years...

I've had luck with a few of PE's small 25 watt plate sub amps, but they don't see the same level of vibration that the bigger 10 and 12" drivers would produce.

I usually make a separated sub-enclosure for the sub amp to avoid the vibration/pressure changes that a normal 11" x 11" plate amp would have to endure... Not an option for you at this point I know, but maybe a good reason to remote-mount your replacement or go with a stand-alone pro-amp for power if you can find one within the budget.

Actually, PE does have add-on plate adaptors for their DSP amps which are pretty thin... This mounting bracket: Dayton Audio SPA-F Subwoofer Plate Amplifier Mounting Frame for SPA250DSP and SPA500DSP (parts-express.com) combined with either of the two amps listed there would be a good option.

You could patch the existing opening with a piece of wood, and go with one of the above options which wouldn't see nearly the level of vibration that your plate amp has seen. Or like I said, just get a decent replacement plate amp and patch the existing cabinet and make a little box for the new plate amp to live in and mount it remotely, avoiding all the pounding it would normally take.

TomZ

[Chris Roemer]

Most ordinarily, amps for ported subs don't have boost (DSP/EQ), normally.

[djg]

Find something used on your local Craigslist equivalent with a blown speaker and a good amp, combine parts, see what happens.

[fpitas]

Most ordinarily, amps for ported subs don't have boost (DSP/EQ), normally.

Conversely, if you use boost with a ported sub be very careful. You can easily get over excursion below the port tuning frequency.

[jhollander]

I prefer the crown XLS for the onboard DSP and adjustable input sensitivity. If auto on is a requirement then the Dayton 5 year warranty is hard to beat. My experience with auto on was not good as I'd find my amp on at weird times. I presumed there was A/C jumping on the LFE cable.

If you have live music outlets like a Guitar Center near you, you could fine some bargain pro amps. Just watch for the input sensitivity. If you have to buy an input boost amp then there's no bargain