What does moving from a 150 watt amp to a 400 watt amp get you?


Hi all, I’m coming back to tap the knowledge of the forum again.  I have a pair of revel ultima studio 2s that I very much enjoy. I’m currently running them with an Ayre V-5xe.  I’ve seen others say that these speakers need to be driven by 400 Watts to get them to sound their best.  I sort of understand the relationship between wattage and sound volume, but if I am not looking for “louder” what do I get with a more powerful amp?  I don’t hear clipping. More current?  But what does that do?  Sorry for my ignorance!
miles_trane

I'm sorry to say that most of the responses you've received are not useful, and some are nonsense.  (There are some good ones too, so don't everybody feel insulted.)

I'll try to help...  In general, more watts are not needed for more volume.  They are needed for more 'headroom'.  In a musical recording, the transients (leading edges of any sound) are MUCH higher amplitude than the rest of the signal.  Having plenty of headroom allows your amp to produce those (fraction-of-a-second) transients at full volume without attenuation or 'clipping'.  That results in a much richer, more robust and more REALISTIC presentation.

It's also true that less efficient speakers will perform better with plenty of wattage & current, because they simply need more power to 'sing'.  I tend to like the sound of low-efficiency speakers mated to powerful amps, but there are many exceptions (& that's my personal taste).

That being said, your Revels are rated at about 88 dB sensitivity w/ nominal 6 Ohm impedance.  That is a moderate, rather than difficult, load, and should not require 400 W/ch.

What's more important is the QUALITY of the amp!  The Ayre V-5xe is a nice-sounding amp. You could easily find a mega-watt amp that is not so well-designed... and take a step BACK in sound.  I would try to audition the Revels with a more powerful amp before spending any $$. You may find that there's no real advantage.

BTW... what pre-amp are you using?  Have you tried a tubed pre-amp?  I've had great success matching solid-state power amps with tubed pre-amps (incl. my current system). That gives you the tight, well-controlled bass associated with solid-state as well as the beautiful mids & highs that only tubes seem to provide.

Anyhow... I hope that helps. 

A correction to a miswording in item 2 of my previous post.  When I said ...
...for a 4 ohm impedance the SPL produced in response to an input of 2.83 volts will be 3 db less than if the spec had been based on 1 watt, since 2.83 volts into 4 ohms corresponds to 2 watts.
I should have said:
...for a 4 ohm impedance the SPL produced in response to an input of 1 watt by a speaker whose sensitivity spec is based on 2.83 volts will be 3 db less than if the spec had been based on 1 watt, since 2.83 volts into 4 ohms corresponds to 2 watts.
Regards,
-- Al
 
I'm hoping you can help me understand this 105db idea better. My speakers, harbeth, are 83.5db sensetivity. If I subtract 10db, add back 3db were at 76.5db. To get to 105db I'd need 30db's provided by the amp (A 1000 watt amp!). I'm a budget audiophile. I run them currently on a parasound 2125 which is 150W @ 8 ohms, 225W @ 4 ohms..  the harbeths are 6 ohms... so based on the chart above I'm likely getting a 22db boost from the amp.. now we're at 98.5db--short of the 105db goal.

My question, sorry I'm a bit of a newbie, is my amp likely clipping? I don't crank music, but listen at a good volume 75-85db spls according to my rack shack meter.  


Which Harbeth speakers are these - the P3ESRs? If so, your amplifier is at the beefy end of what they can handle.
If not, the bigger Harbeths are more sensitive than this. How big is your room?
Robertjason75, to add to Willemj’s questions and comments, as I alluded to in the last paragraph of my lengthy post yesterday I don’t think that for most listeners the capability of cleanly producing 105 db peaks at the listening position is necessary on most or all of their recordings. And I believe that a majority of audiophiles do not have systems providing that capability.

And even though as I mentioned I listen to a lot of classical symphonic recordings that have been engineered with minimal or no compression, and consequently have extremely wide dynamic range, that I listen to at average volume levels of perhaps 75 db or so, there are relatively few recordings in my collection which will reach brief dynamic peaks in the area of 105 db. (In addition to basing that conclusion on SPL measurements I have performed using a Radio Shack digital SPL meter set for fast response and C-weighting, I have used a professional audio editing program on a computer to examine the waveforms of some of the widest dynamic range recordings in my collection. Doing so readily allows me to determine the full amplitude of even the briefest high volume transients, and compare it to the average level of the recording).

So without knowing what kinds of recordings you listen to, or the answers to Willem’s questions, my guess is that you don’t have a problem.

Regards,
-- Al