Stock subs, 50 watt rms or peak?

[J Wikoff]

I'm piecing together a shelf stereo for my garage. I have an amp that has a sub channel stable to 4 ohm at 68 watts. Don't know if that's peak or rms just yet. I thought I might use one or both of the old stock G8 subs which are 2 ohm and have 50 watts stamped on the back. I figure I'd have to use both, wired serial to play nice with the amp, but I'm not sure if the power will be sufficient. If they are 50 watts peak, it might be ok. Thoughts?

[STL_G8GT]

I'm piecing together a shelf stereo for my garage. I have an amp that has a sub channel stable to 4 ohm at 68 watts. Don't know if that's peak or rms just yet. I thought I might use one or both of the old stock G8 subs which are 2 ohm and have 50 watts stamped on the back. I figure I'd have to use both, wired serial to play nice with the amp, but I'm not sure if the power will be sufficient. If they are 50 watts peak, it might be ok. Thoughts?

As long as you don't drive the amp into clipping you should be just fine, rms or peak, the numbers are close regardless. At that power level, no issues.

Building an acceptable enclosure will be the greater challenge... Id build the biggest box possible and adjust port length based on performance, 3" or 4" dia.

[J Wikoff]

I should be fine with just one 2 ohm sub, or with two in series?

[norm8332]

FYI: I left the stock subs in and installed an amp. I regularly (years) have put 150W peak (measured) into the stock subs without any kind of degradation or failure. They are pretty forgiving with music power. Like said above, just keep it below the level of when the amp or speakers clip.

[J Wikoff]

So 50 is likely their RMS. That helps to know. Thanks!

[STL_G8GT]

I should be fine with just one 2 ohm sub, or with two in series?

You need to wire both subs in series to get 4ohm load.

Amp sub channel + to sub 1 +, then sub 1 - to sub 2 +, then sub 2 - to amp sub channel -.

[J Wikoff]

I tried last night, with one stock G8 sub and this amp. It sounds decent in lower volume situations, but when I turn it up the sub pops somewhat. I'll try wiring the second sub in series this evening and see how that goes.

https://www.parts-express.com/dayton...pply--300-3830

[norm8332]

Does that amp support two ohms? Yeah try them in series.. That amp is not going to be able to put out 2X50 Watts (100W) when it only comes with a 48W power supply Watts=Voltage times Amperage with DC.


The specs claim 4 ohm minimum. They are a bit sketchy if you ask me.

Specifications: • Speaker power output: 50 watts x 2 • Subwoofer power output: 100 watts • Impedance: 4-8 ohms • Amplifier input voltage: 24 VDC • Amplifier input amperage: 4A • Power supply voltage: 100-240 VAC, 50/60 Hz • Power supply amperage: 2A

Note that it says Amplifier input amperage 4A, but it only comes with a 2A power supply.

[J Wikoff]

The amp manual says 4 ohm min, but the data sheet for the chips in the amp say 2 ohm, and some reviews say they use 2 ohm just fine. So I thought I'd give it a try.

[norm8332]

Yeah, I think it's not an adequate power supply it's only 48W. How do they expect to get 50W X 2 and 100W sub woofer is beyond me. And you could only get 48W continuous on one channel if the amp was 100% efficient and it is not, more like 80% for class D. That means 38W total combined continuous output in real life. I think that amp is "creatively rated". It would probably work better with a 24V 5A power supply.