how do you work out if an amp is able to drive your speakers?

[STEVE R]

I am going to make my ignorance very obvious but how do you know whether an amp is suitable for your speakers in terms of what is required to drive them? (apart from trying it out of course). I have recently bought some Acoustic Zen Adagios and want to know if a Levardin IS Reference would be ok to partner with them for example.

Sorry if this sounds really basic!

 

[Purite Audio]

The first step would be to look at the specification of your loudspeakers and of the amp, the manufacturer should provide an efficientcy rating in dB at a nominal impedance.

Keith.

 

[alexh]

Turn it up until it goes BANG, then back it off a little

 

[simon g]

The first step would be to look at the specification of your loudspeakers and of the amp, the manufacturer should provide an efficientcy rating in dB at a nominal impedance.Keith.

I think you're confusing sensitivity with efficiency.

 

[Purite Audio]

Yes you are quite correct,

Sensitivity – The sound pressure level produced by a loudspeaker in a non-reverberant environment, often specified in dB and measured at 1 meter with an input of 1 watt (2.83 rms volts into 8 Ω), typically at one or more specified frequencies. Manufacturers often use this rating in marketing material.

Most loudspeakers are highly inefficient,

Keith.

 

[ob1]

The load dipping when you turn the rig up is rather important too. Manufacture's spec sheets doesn't tell you everything that they should and it's quite hard to really get the true idea of how the speakers will preform with a certain amp.

In this case though, the Adagio do like power up them. I know that many Acoustic Zen owners are quite happy with low watts tubes amplification but when I had the Adagio, at certain volume say 75dB (roughly) the sound become noticeably brighter with 20 watts valves pushing speakers. I do remember quite clearly, what GamuT D200 mk3 did to the same pair, the sound was totally effortless and quite amazing real even at high volume.

Back to the question, I think 30 watts Levardin IS would be fine driving the gorgeous adagio in most room size, as long as you are not try to make a concert sound out of them.

 

[SergeAuckland]

The amplifier's specification will (or should) say what the minimum load impedance can be, and/or it will give a power measurement into 8 and 4 ohms that shows low well the amplifier drives the more severe load.

The loudspeaker specification shoul provide an impdance curve that shows how the loudspeaker's load changes with frequency. If the loudspeaker's impedance is always more that the amplifier's minimum, the the amp will drive the 'speakers fine. If it isn't, then depending on where the minimum is, it may ormaynotmatter. For example, a loudspeaker with a minimum at 100 Hz will stress an amplifier much more than one with a minimum at 10kHz as there's far more energy in music at LF than at HF.

S

 

[RobHolt]

Yes you are quite correct, Sensitivity – The sound pressure level produced by a loudspeaker in a non-reverberant environment, often specified in dB and measured at 1 meter with an input of 1 watt (2.83 rms volts into 8 Ω), typically at one or more specified frequencies. Manufacturers often use this rating in marketing material.

Most loudspeakers are highly inefficient,

Keith.

All loudspeakers are highly inefficient - even 'efficient' ones.

The choice is between very inefficient and amazingly inefficient

 

[rod]

Acoustic Zen Adagios according to their web page are 89db@ 1 mtr **

89db spl for 1 watt

92 for 2

95 for 4

98 for 8

101 for 16

104db for 32watts @ 1mtr

Usually this measurement** is based on 8 ohms and the adagios are 6 ohm...

so this is gives a rough idea

lower impedence(6 in this case) gives higher db as long as amp has stiff enough power supply

 

[Purite Audio]

All loudspeakers are highly inefficient - even 'efficient' ones.The choice is between very inefficient and amazingly inefficient

Yes quite, how efficient are 'efficient' speakers in terms of percentage of power turned into acoustic output do any get into double figures?

Keith.

 

[SergeAuckland]

Yes quite, how efficient are 'efficient' speakers in terms of percentage of power turned into acoustic output do any get into double figures?Keith.

According to John Crabbe's excellent book, 'HiFi in the Home', on page 178 he states that most loudspeakers come in the 3-6% efficiency region, with small sealed-boxes being below 1%, although large horn-loaded 'speakers with high-flux magnet systems could be up around 30%.

However, that was written in 1968. Using http://www.sengpielaudio.com/calculator-efficiency.htm this indicates an efficiency of 0.2% for an 85dB/watt loudspeaker, a Tannoy at 92dB/W is 1% efficient.

Eficiency isn't something I'm very hung up about, as most of the loudspeakers I've liked have been relatively low efficiency designs and power is cheap!

S.

 

[Purite Audio]

Even I am more efficient than that!

Kr Keith.

 

[SergeAuckland]

Even I am more efficient than that!Kr Keith.

Efficiency isn't that important, effectiveness is much more so! ;-)

S

 

[paulf-2007]

I was showing someone pictures of my 200Hz horn and its housing today and his comment was " you will be able to hear that all over town ". I then told him I use less than 1 watt to drive them. He looked blankly at me, so I left it at that. :doh:

Yes you are quite correct, Sensitivity – The sound pressure level produced by a loudspeaker in a non-reverberant environment, often specified in dB and measured at 1 meter with an input of 1 watt (2.83 rms volts into 8 Ω), typically at one or more specified frequencies. Manufacturers often use this rating in marketing material.

Most loudspeakers are highly inefficient,

Keith.

 

[Leonard Smalls]

I was showing someone pictures of my horn. He looked blankly at me, so I left it at that. :doh:

:shock:

 

[STEVE R]

I'm not sure if I am any the wiser!

At least someone thinks that the amp will be ok with the speakers at any rate........

Thanks for the replies.

 

[SergeAuckland]

I'm not sure if I am any the wiser!At least someone thinks that the amp will be ok with the speakers at any rate........

Thanks for the replies.

Sadly, the Lavardin website gives zero technical information on their amplifiers other than airy-fairy stuff about "New electron flow" so one can't get any information about what their amps actually do.

Similarly, Acoustic Zen gives next to ne detail on their loudspeakers, and their 'technical' section bangs on about their cables rather than anything substantive.

I'd say it's a marriage made in heaven. An amplifier that one has no idea what it does together with a loudspeaker one has no idea what it needs.

Why do I hate HiFi...........

S.

 

[Micke Y]

how do you work out if an amp is able to drive your speakers?

1 Turn it up loud with some nicely recorded metal and if you can hear distortion then its not powerful enough.

2 Put on some choir music and if the voices are clean then everything is OK (this is very rare indeed)

Michael

 

[Joelsim]

I'm not sure that in my whole lifetime I've ever encountered an amp that can't drive my speakers, no matter whether they have been 8 or 4.

If you live in a palace then maybe it may be a slight issue.

At the end of the day it's about an amp and speakers working in harmony, to my mind this isn't about power. Unless you have a very weak valve amp.