watts and ohms
Apr 22, 2002 at 3:39 PM Thread Starter Post #1 of 18

Shinjuku Boy

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will an intergrated amplifier with 50 watts per side into 8 ohms and 80 watts
into 4 ohms be enough for 1 pair of speakers with 180w and 4ohms?

i suppose not but im not sure.
 
Apr 22, 2002 at 5:08 PM Post #2 of 18
If the speakers have an average impedance of 4 ohms and can handle 180 watts of power, the amp with 50 watt/channel should be able to drive them (or 80 watts/channel at 4 ohms). Basically, the power rating on speakers usually refer to how much power they can handle before bad things can happen.

Basically, your amp cannot drive your speakers to their maximum volume, and probably cannot drive them to their maximum fidelity either. I really don't know how amplifiers work, but if you listen to them at low enough volumes, the amp should provide enough current.

I bought a yamaha amp long time ago to drive my monitor audios. I think my monitor audios had too low of an impedance and damaged my amp permanently. After replacing the amp with a Rotel amplifier rated at half the power rating, my speakers sounded much better. Goes to show that the power rating on an amplifier depends how the manufacturer publishes their numbers. A good company publishes power outputs where the amp can perform well, not its absolute maximum output (or they indicate maximum output and put a disclaimer saying that extended periods of time operating at such output levels is damaging or explain that the figure is the maximum instantaneous output).
 
Apr 22, 2002 at 5:51 PM Post #3 of 18
Quote:

Originally posted by Shinjuku Boy
will an intergrated amplifier with 50 watts per side into 8 ohms and 80 watts
into 4 ohms be enough for 1 pair of speakers with 180w and 4ohms?

i suppose not but im not sure.



The 180W is the max powering handling ability of the speakers and is irrelevant to the question you are asking. The factors that are pertinent to whether or not 50 watts @ 8 ohms is enough are:

1. The efficiency of the speakers in question (measured in DB).

2. The volume of the room the speakers are in.

3. How loud you want to play them before they start clipping.

4. Weather or not the amplifier really puts out 50 watts across the frequency range. A lot of manufactures of amps exaggerate their capabilities.

In general, 50 watts is enough to drive most speakers quite loud before clipping in most normal size rooms in ones house. What speakers and amp are you talking about?
 
Apr 22, 2002 at 6:09 PM Post #4 of 18
In the US, the rating of an amplifier at 8 ohms is the amount of power the amp can output into an 8 ohm resistor for an hour without melting down (unless this changed lately when I wasn't looking). A more conservative rating would be 20-20KHz, which simply replaces the 8 ohm resistor with a variety spanning the range. Neither rating means anything in the real world.

Music is highly dynamic, and loud passages requiring the maximum output of the amp last fractions of a second, not hours. Further, a speaker is not a constant impedance load, but rather a variable one that changes with the frequencies going into it. So, manufacturers started building amps that had lower ratings, but greater dynamic headroom, that is, the ability to output an amount of power greater than their rating for a short burst of time.

A 30 watt amplifier with a lot of headroom can actually power speakers much better than a 50 watt amp that has none.

This is my long-winded way of saying that there's simply not enough information to answer the question.

FWIW my main amp is rated at about 65 wpc, and can play B&W Matrix 804's LOUD without clipping. It's also got a huge power supply, and I suspect it may have a few watts in reserve...
 
Apr 22, 2002 at 9:04 PM Post #5 of 18
Speaker specs:
Impendance 4 Ohm
Sensitivity 93 db
Power handling 120 W (funny, the note on the back of the speakers say 180w)
Frequency range 30-20 000 Hz .

They are in a normal sized room, my room. In the basement of a house without neighbours to complain. I suppose the clipping you were talking about is at a volume.. Example, i put some music on and i want to hear it as good when i go upstairs? But no i don't need that. Im just looking for fidelity and good bass.

That is the primary reason why i don't like my current one. Deep bass just rumbels and makes otherwise good tracks bad. It also puts out to much background noice so i can forget enjoying ambient, classical or more minimalistic music.

This is the new amplifier im thinking of buying. The price is 242 USD.
Linn Intek
http://linfo.linn.co.uk/binaries/5A2...ers_manual.PDF
 
Apr 22, 2002 at 9:41 PM Post #6 of 18
Clipping is a electrical state when the output exceeds the limit of the amp in voltage or current. It will sound like clicks and pop (sound is breaking up). This typically is at very high volume.

"It also puts out to much background noice so i can forget enjoying ambient, classical or more minimalistic music. "

This doesn't sound normal. You must have a lot of noise from your amplifier/source. I suspected you have either a defective amp or noise problem in your set up. I doubt higher power will solve this problem.

Anyway, I can't read the data sheet of the Linn amp. But based on the power spec you described, it is a capable amp. Depends on the speaker you use, this might be adequate. For difficult load, you might want to look at used Adcom instead.
 
Apr 23, 2002 at 4:35 AM Post #7 of 18
Quote:

Originally posted by Shinjuku Boy
Speaker specs:
Impendance 4 Ohm
Sensitivity 93 db
Power handling 120 W (funny, the note on the back of the speakers say 180w)
Frequency range 30-20 000 Hz .

They are in a normal sized room, my room. In the basement of a house without neighbours to complain. I suppose the clipping you were talking about is at a volume.. Example, i put some music on and i want to hear it as good when i go upstairs? But no i don't need that. Im just looking for fidelity and good bass.

That is the primary reason why i don't like my current one. Deep bass just rumbels and makes otherwise good tracks bad. It also puts out to much background noice so i can forget enjoying ambient, classical or more minimalistic music.

This is the new amplifier im thinking of buying. The price is 242 USD.
Linn Intek
http://linfo.linn.co.uk/binaries/5A2...ers_manual.PDF


At 93 db your speakers are very efficent and your amp should drive them fine. Your lack of bass is mostly likely caused by the speakers limitations. A more powerful amp will not help. Solutions are to get a powered subwoofer or speakers that go lower. If you can afford it ($300 ish is the starting point for something half decent) the powered subwoofer is the better solution. I use a HSU VTF2 which I like alot and sells for around $400 - $450.

Nick
 
Apr 23, 2002 at 5:22 AM Post #8 of 18
quick note: for anyone who doesn't know, every time you double the power rating of an amp, you get 3db more volume. so a 50 watt amplifier will only be 3db quieter than a 100 watt one, and in most cases you'll never use that extra 3db of volume. just a reminder
smily_headphones1.gif
 
Apr 23, 2002 at 8:36 AM Post #9 of 18
the noise problem comes from my amplifier i assure you, it's as old as me i think. 20 years
smily_headphones1.gif
. 220V. 180W; 50Hz is all the back of it says.

can anyone read the adobe acrobat linn intek manual?
i thought about posting some info, but i don't know if i'll miss something important.

im buying it as soon as i can a definite answer(if possible).

i really appreciate what you people are doing, i did'nt understand much of all this compatability and techinal stuff.
 
Apr 23, 2002 at 3:01 PM Post #10 of 18
Quote:

Originally posted by Shinjuku Boy
the noise problem comes from my amplifier i assure you, it's as old as me i think. 20 years
smily_headphones1.gif
. 220V. 180W; 50Hz is all the back of it says.


Shinjuku, you are barking up the wrong tree. Most of what you hear from your audio system is based on speaker choice, room acoustics and speaker location. About your 20 year old amp, some folks think that the old amps are superior to the ones you buy today. Food for thought.

Nick
 
Apr 23, 2002 at 4:10 PM Post #11 of 18
Im checkin out the german intruction manual to my current old Sansui 661, and im trying to compare this aone and the Linn Intek.

The non technical data part of the Sansui manual says:
.
the differential amplifier in the entrance and the double supply voltage fur + and - result in an effective sine achievement of full 32 w for each channel (at 8 ohms with 1 kHz pure tone) the achievement range of the output stage is with 15 - 40000 hz cycles per second amazingly roughly, the gesamtklirrfaktor and the intermodulation distortion are appropriate more under for 0.5%.


The technical data sheet is shown exactly like this:

Sine achievement (effective DIN)
with enterprise both channel 2 x 27 w on 8 Ohm with 1000Hz

with operation of a channel 2 x 40 w on 4 Ohm with 1000Hz
2 x 32 w on 8 ohm with 1000Hz

music achievement(IHF) 110 W on 4 Ohm with 1000Hz 75 W on 8 Ohm with 1000Hz.
-----------------------------------------------------------------------------------

Linn Intek:

Load impedance: Two pairs of 4 Ohm loudspeakers may cause the overcurrent protection trip to operate at moderate volume levels.( i only need to drive 1 pair of 4 ohm loudspeakers).

Outputs:
Maximum output power 50 watts / 8 ohms per channel
80 watts / 4 ohms per channel.

Is this enough information for someòne to deside which one is better?
 
Apr 25, 2002 at 10:48 PM Post #13 of 18
please help me out. i would'nt try to speed it up like this if i had alot of time. i don't know if someone else will buy it before me and its the best offer yet.

just say if there is more information "you" need.
 
Apr 26, 2002 at 12:01 AM Post #14 of 18
Shinjuku;

Spec wise, the Linn is better. But since I don't know anything and have no experience with this amp, I can't say for sure the quaility of the amp.
 

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