Need Power amplifier Recomendations 1000.00 or less 500 watt minimum @4ohm.

[MRC01]

I think the log/exp relationship of SPL to power throws people off when they make ballpark estimates.
Even my inefficient Mag 3.6/R produce SPLs in the 90s with about 10 W output. That's very loud. But reaching the THX recommended 105 dB SPL takes about 30x more power, now we're talking about 300 watts!
I agree -- when it comes to power, better to have it and not need it, than need it and not have it. So long as excess power on a fixed budget doesn't mean compromising sound quality.

 

[HammerSandwich]

The median measured number is 86dB/2.83V. But a greater number of speakers fall below that number than above it...

I don't wish to split hairs, but that's completely opposed to everything I learned about medians.

Regardless, taking 86-87dB/dBW seems to be a safe bet.

 

[HammerSandwich]

...my(600W SDS-470C) class D amplifier consumes 175-400W. So, this is clearly not true. Even counting some power supply loss that's at least 10x more power than 10W rms.

The difference between 10W & 400W is 16dB, which is within reason for high-DR music. Even more so, if "consumes" means that you measured at the amp's AC input, because even Class-D isn't 100% efficient. 10Wrms might be unreasonable with speakers that can't do [email protected].

 

[Sancus]

The difference between 10W & 400W is 16dB, which is within reason for high-DR music. Even more so, if "consumes" means that you measured at the amp's AC input, because even Class-D isn't 100% efficient. 10Wrms might be unreasonable with speakers that can't do [email protected].

Yeah, that's how I measured, and agreed it's definitely not 100% efficient, probably something like 90%. Was just meant to illustrate that 10W is definitely insufficient for some speakers in some rooms, at least.

 

[HammerSandwich]

Agreed 100%. Amps need to provide more than RMS power levels, no question.

 

[andreasmaaan]

I don't wish to split hairs, but that's completely opposed to everything I learned about medians.

Regardless, taking 86-87dB/dBW seems to be a safe bet.

Haha yes! Obviously I should have swapped average and median in that post

 

[Ron Texas]

Interesting thread which has been sleeping for over a year. In the meantime a Crown XLS1502 was tested here with the result being a so-so SINAD of around 76db. I recall in the review thread @mitchco posting he used the Crown to make binaural recordings of his recently purchased LS50's and nobody said anything was amiss.

Our host has estimated an Emotiva PA-1 to have an 86db SINAD from it's published specifications. Would I hear a difference from the Crown? I doubt the reduced power of the PA-1 would be a factor since the extra power of the Crown would easily drive the LS50's into distortion.

There is the bass management issue. XLS amps have a built in DSP which may be used to set up a high pass for the mains. With the Emotiva (any Icepower or Hypex) based amp, I need to add something. Another member around here recommended using something like this:

https://www.parts-express.com/harrison-labs-fmod-inline-crossover-pair-100-hz-high-pass-rca--266-274

It's 12db/octave, passive and cheap.

So, I wonder if a significant improvement is possible with a pair of PA-1's and some Harrison plugs, or is it just throwing money at an imaginary problem?