[mc whak]

This has nothing to do with headphones, but if anyone can answer my questions I'm sure you all can.

I noticed that alot of their amps only output 8WPC-22WPC. Now, that to me doesn't seem very good. I was interested in their new "The Wave AV-8" monoblocks. Only $99 each. But they only put out 8WPC. If my speakers are 20W min, 100W max 8ohms, will these just not work?

 

[chych]

Heh yeah, your speakers will basically sound too quiet if any sound at all... I suppose the ASL amps are more geared towards more efficient speakers.

 

[rickcr42]

it depends a lot on where and how you listen.Generally you would not use an amp of 10 watts or less with a speaker of less than 92 db/1w/1m or so.However if you do not listen at loud levels and you are in a smallish room or sit close then you may get by with speakers of 89db/1w/1m sensitivity

 

[bootman]

Wattage ratings on speakers are really useless IMO. Its the sensitivity rating thats important. It will determine how much power you will need to acheive a given sound level. It might surprise to to find out that for a normal volume level. (90db or so) your amp is only putting outs a few watts worth of output. Of course more power is needed if heavy transients are present in the music. (load bass passages for example) but this is only for the duration of the transient.

 

[rickcr42]

bootmamn is correct,the other thing to look at is the impedance curve of the speaker.Even if rated at 8 ohms it may dip low which is not much of a problem with transformer coupled tube amps but could cause big time problems with low power transistor amps (like my ZEN)

 

[Neruda]

yup, you gotta love fullrangers and horns...some of them can be powered with just one watt.

 

[mc whak]

(Said like Butthead)Uhhhh, okay.

(Return to normal voice)Could you all do me a favor? Give me the link(s) to a place or places that explain the whole:

"it depends a lot on where and how you listen.Generally you would not use an amp of 10 watts or less with a speaker of less than 92 db/1w/1m or so.However if you do not listen at loud levels and you are in a smallish room or sit close then you may get by with speakers of 89db/1w/1m sensitivity"

I just don't understand the logic behind it. I was under the impression that 87db, the efficiency(?) of my speakers, meant that it could go that loud before distorting. But if 10W works with 92db, but not 89db...I'm lost.

Help a brutha out.

 

[rickcr42]

OK dude,away we go....................

Say you have a loudspeaker with a rated sensitivity of 90 dB SPL for 1 Watt input at 1 meter.What that means is you will be getting a volume level of 90 dB average if you are sitting one meter from the loudspeaker.Peaks are of course higher as is amplifier power,a 10 watt amp can hit peaks of higher power,the rating is for continuous average power

Now hit that same speaker with 10 watts and you get 100 dB SPL at the same seating location,5 watts would be 95 dB and so on.

If you listen "nearfield" such as with computer speakers then this is plenty of volume,but put that same set up in a large room and you will run out of steam,especially in the bass notes.

But if you take that same amp and mate it to a loudspeaker that has a sensitivity rating of 95 dB SPL/1 Watt/1 Meter and you get 105 dB with 10 watts,pretty damn loud for all except loud rock,very loud rock,then you would want a speaker with a sensitivity of 98dB with the same amp

Hope this was helpful

Rickasaurusrex

 

[rickcr42]

While on this subject I just thought I would add how it really amazes me how many folks try to mate the wrong speaker to the environment they use it in.Trying to squeeze a system with a 15 " woofer into a small room or "nearfield" listening is just plain goofy,as is expecting a 5" woofer to fill a large room with bass.Simple laws of physics dictate that you have to move air to produce bass notes with volume but use that same woofer in a small room and you get a system without enough room to breahte.A big woofer actually gets louder as you move away from it,a small woofer loses steam

 

[crk]

Err... what follows is actually not terribly important but.....

SPL is measured in dB which a logarithimic scale so if 1 Watt gives 90 db, 2 Watts will give 93 dB, 4 Watts 96 db and 8 Watts 99 db.
Well as I said it is not very important...

More to the point is that one needs to allow for a sufficient overhead in the power rating, i.e. the comfortable listening level should require an average amp power significantly less than the maximum. (The TI guide rick referenced in the DIY CD thread is a good place to start). So with an 8W amp, I reckon you'd want speakers with a much greater sensitivity than 90 db/W.
crk

 

[rickcr42]

correct (the rickster should not answer many threads at same time)
I use speakers at my computer rated at 89dB spl and power them with a 20 watt tube amp.Way more than enough for sitting at the computer

My main system is actually underpowered in some areas.I run 10 watts at a combination of 89 db satellite and a padded down DIY woofer under each that normally would be rated at 95 db spl.I get away with it solely because I also have a corner sub with its own amp and when combined with the rear speakers aounds fine due the cumulitive volume of all the speakers together

 

[RGA]

Mc Whak:

Some of the explanations above while good, may still confuse you a bit so here is a bit of help with the basics of Sensitivity and watts. The following refers to continuous average power output:

Say you have a speaker rated at 89db sensitive 1Watt/1meter. That means that you will get 89db(of volume) with just 1 watt of power. For every 3db increase in Volume...you need a doubling of the watts to get that 3db.

So: 89db = 1Watt
92db = 2 Watts
95db = 4 Watts(doubles 2)
98db = 8 Watts
101db = 16Watts
104db = 32Watts
107db = 64 watts
110db = 128Watts
113db = 256 watts

Something you should be aware of is that it requires a 10db increase to get what is perceived as a doubling of the volume level. So, if you use the Wave 8 with an 89db sensitive speaker you are looking at a max of about 99db. Since your speakers are rated at 100Watts max then you can only get around 108db...no matter what amp you use(if the sensitivity is 89db).
95db is very loud...116 is near concert level...140db is a jet engine at 10 feet

You can see that if you have a speaker rated at 95db sensitive(like mine) then the scale above shifts so that 8Watts would produce 104-105db.

Now there are other variants...for instance the sensitivity rating is often innacurately measured. While the tweeter may be 95db the woofer may only be 87db...my bet is manufacturers split the difference. Bass often requires far more power which is why tubes sometimes make the bottom end a bit fuzzy...it's nice fuzz...but solid state amps will usually give more presence in the bass department. They also give more presence in the high frequencies which can sound shrill...which is why tube owners hate them, and why many Solid State owners eventually buy tubes.

I recently heard an 11 Watt integrated tube amp driving the B&W Nautilus 801s at a difficult 89db(B&W's impedence curve makes them harder than there spec sheet indicates). http://www.bwspeakers.com/products/g...1E0000E20E7DA6

at the end of the day Watts are not that important...If your speakers are rated at over 90db...you will get reasonably good volume levels...better yet...the Wave 8s will likely beat any solid state amp at twice or maybe even 3 times the price.

I have not heard them yet ... but other ASL amps are terrific and the design and build is quite solid. Check out reviews at UHF. Probably the toughest group of reviewers to impress. http://www.uhfmag.com/Issue58/Antique.html

 

[morphsci]

I have a pair of ASL AV-8's. I run them through a biwired pair of Wharfedale Anniversary 7.2's. The speakers are rated at a nominal 8 Ohm impedance and a sensitivity of 89 db. I use them in our den which is approx. 12' x 18', carpeted with three walls paneled. It is plenty load for me and so far has never sounded strained. But this is after only about two weeks of listening. So far I am very pleased with the sound of the Waves. The construction is average, but then again they only cost abot $230 for a pair (With tube cages and removable plugs). I am constructing some beefier power cables for them so we'll see if this AC cord hysteria has any truth to it

 

[jmpsmash]

thank you RGA for the explanation.

so let me get this clear...

a exponential increase (x2) in power give a linear increase (+3db)in decibels.

while a linear increase in decibels (+10dB) gives exponential increase in loudness.

does that means linear increase in power gives linear increase loudness?

in other words, does that mean, if i double the power of my amplifier, running at it's max output, and for simplicity sake, running only the woofer, i should get twice the perceived loudness?

 

[Neruda]

I always think it's funny how people want more and more power, when that power is usually giving them three or four more decibels of volume, which aren't being used anyway