Easy Stereo Add-on

[Jimmytee]

Attachment 15518

What model speaker is that? the DB series?

[Dirtstiff's F6B]

What model speaker is that? the DB series?

They are -
Polk DXI 651 s which are 80 watt RMS.

[Dirtstiff's F6B]

They are -
Polk DXI 651 s which are 80 watt RMS.

Driving them with a Polk 200 watt per channel PAB 2000.2 amp. They sound pretty good.

[Jimmytee]

They are -
Polk DXI 651 s which are 80 watt RMS.

Looks like they're rated for 55 to 60 watts RMS. http://www.amazon.com/Polk-Audio-DXI.../dp/B00FEYXTT6
http://www.crutchfield.com/S-b9xzeDI...o-DXi651s.html

Running more than that shouldn't be an issue if you set the amplifier gain control to help keep from over driving them. More speakers are damaged from too little wattage than too much.

[Dirtstiff's F6B]

I stand corrected
The DXI 6.5 are
6 - 60 watt RMS with 180 Peak.
The DXI 651s - shallow mount are appx 5 watt lower.

I will likely end up with the MM 651 Polk. 100 watt RMS rated.

I also believe the sound would be best doing what JT did in finding the input to the oem amp.
Thanks

[Jimmytee]

I stand corrected
The DXI 6.5 are
6 - 60 watt RMS with 180 Peak.
The DXI 651s - shallow mount are appx 5 watt lower.

I will likely end up with the MM 651 Polk. 100 watt RMS rated.

I also believe the sound would be best doing what JT did in finding the input to the oem amp.
Thanks

The best sound I achieved with the OEM stereo was like you mentioned , finding the preouts to the OEM amplifier and using them to feed the after market amplifier. But now I have seen the light, or at least heard it. I am no longer using anything OEM in the stereo system.

[53driver]

...Running more than that shouldn't be an issue if you set the amplifier gain control to help keep from over driving them. More speakers are damaged from too little wattage than too much.

Amplifier gain settings will NOT (in all amps I have ever been associated with) limit the output to a reduced wattage. The only thing that will limit the amp's output is something that limits its input.

Totally concur with "more speakers are damaged from too little wattage..."

[Jimmytee]

Amplifier gain settings will NOT (in all amps I have ever been associated with) limit the output to a reduced wattage. The only thing that will limit the amp's output is something that limits its input.

Totally concur with "more speakers are damaged from too little wattage..."

Yes, the gains are used to match the pre out voltage to the amplifier's input gain structure, but you can use this to limit the maximum volume that you achieve. Doing by ear, you could decrease the gains until you achieve the ability to turn your source volume up without audible distortion in your speakers. Yeah, it is just a way to adapt. Of course the more accurate way to adjust gain control is by using a DMM and adjusting the gains to the desired voltage that will avoid the amplifier clipping. The desired voltage is dependent on the RMS rating of the amplifier and the impedance or load that wattage is driving.

Voltage = square root of the (wattage x impedance)

[53driver]

Yes, the gains are used to match the pre out voltage to the amplifier's input gain structure, but you can use this to limit the maximum volume that you achieve. Doing by ear, you could decrease the gains until you achieve the ability to turn your source volume up without audible distortion in your speakers. Yeah, it is just a way to adapt. Of course the more accurate way to adjust gain control is by using a DMM and adjusting the gains to the desired voltage that will avoid the amplifier clipping. The desired voltage is dependent on the RMS rating of the amplifier and the impedance or load that wattage is driving.

Voltage = square root of the (wattage x impedance)

I use this equation to set my limiters:

20log(((sqrt(program wattage of speakers * impedance of speakers)) / amplifier gain) / 0.775)
Amp gain number is in "X" format, like 40X.
This yields proper dBu for setting limiters in sound processors.
This will limit the input signal so it cannot drive the amp past speaker ratings.