Amplification "Headroom" and Sierra-1s

[cynan]

I'm thinking of getting a power amplifier for my sierra-1s. My option is to go with one rated at 120 watts RMS per channel (wpc) into 8 ohms or go with one rated 240 wpc into 8 ohms. I realize the 120 wpc version will be enough power for the Sierras (I currently run them off of an integrated amp that maxes out at about 55 wpc into 8 ohms with great results). However, will I notice any difference in dynamics by going with the extra headroom? The difference in cost between the 120 wpc and 240 wpc is only about $60...

Any opinions?

[curtis]

You can use this calculator to help you gauge how loud things can get with either setup.

http://www.stageaccompany.com/en/support/splcalc.php

[cynan]

Thanks for the link. However, I'm not so interested in SPL levels. I'm more interested in the increase in dynamics more amplification can provide (to a certain level) and, in that vein, was wondering if 240 wpc would provide any discernable increase in dynamics over 120 wpc. I'm leaning towards "probably not". However, given the modest price difference between these amplifiers, I'm undecided which to go with.

[curtis]

Thanks for the link. However, I'm not so interested in SPL levels. I'm more interested in the increase in dynamics more amplification can provide (to a certain level) and, in that vein, was wondering if 240 wpc would provide any discernable increase in dynamics over 120 wpc. I'm leaning towards "probably not". However, given the modest price difference between these amplifiers, I'm undecided which to go with.
Dynamics relates to SPL levels. The speaker is more dynamic if the differentiation between its lowest level it can play to the highest is larger at any given time. Dynamic range is measured in decibels.

With a more powerful amp, you can achieve higher and cleaner peaks(SPL), thus being more dynamic.

All things being equal, a 240wpc channel amp will be capable of 3dB louder peaks than a 120wpc amp.

Currently, with your 55wpc amp and two Sierras, you are capable of 97dB peaks at distance of 3 meters. With 120wpc, that increases to 101dB, and with 240wpc it is 104dB.

Now, if you don't play your music loud enough to take advantage of the extra power, then it would not make any difference. If you listen to your music at an average of 85dB, and the music has a 15dB peak(which is not uncommon) with your 55wpc amp, you would not hit the peak and not realize the full dynamics of the music. With the 120wpc amp, you would.

[cynan]

Yes. What you write is correct. I guess what I meant was that I'm not interested in trying to hit greater overall spl levels, but in having enough headroom to hit peaks, offering a full dynamic range at my nominal listening SPL, as you address clearly in the last paragraph.

I suppose I need to establish what my max normal listening level is - probably not more than 85 db. However, this can be difficult to determine without resorting to data-logging with an SPL meter across different genres of music. Also, you say that 15 db peaks from nominal spl is not uncommon - is this for particular type of music or a general figure?

Thanks for your input, Curtis!

[curtis]

Yeah...understanding your listening levels would help.

Scroll down this page and you can see the loudness levels of certain music/instruments. It might help.

http://www.hearnet.com/at_risk/risk_trivia.shtml

[RicardoJoa]

For 60 bucks, i will get the 240 watts amp, assuming that both amps are same in terms of quality. Usually thing doubles.