I have an 80 wpc amp and am thinking of replacing my speakers.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.
Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?

wrote:
I have an 80 wpc amp and am thinking of replacing my speakers.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.
Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?



A very interesting question!

As I recall from many years ago, low end performance and sensitivity
could to some extent be played off against each other: That is to say,
that for a particular cost, a 'speaker could either go deep in the bass,
or be sensitive, but not both. To achieve greater low frequency
performance with greater sensitivity requires a much stronger magnet,
hence more cost.

When size of box is also factored in, then a small box can go low but
not loud, and vice-versa.

What all this distils down to, as far, again, as I recall, is that cost,
size, bass performance, sensitivity and maximum loudness are all
interrelated.

If I were in your position of having 80 watts available, this is
sufficient for quite high levels with 'speakers of average sensitivity
(say 86dB/watt) so I would choose on the basis of sound, size and cost.
Choosing very sensitive 'speakers (say 100dB/watt)could bring the
noise levels up to be noticeable and make the volume control very touchy.

S.

Serge Auckland wrote:
wrote:
I have an 80 wpc amp and am thinking of replacing my speakers.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.
Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?



A very interesting question!

As I recall from many years ago, low end performance and sensitivity
could to some extent be played off against each other: That is to say,
that for a particular cost, a 'speaker could either go deep in the bass,
or be sensitive, but not both. To achieve greater low frequency
performance with greater sensitivity requires a much stronger magnet,
hence more cost.

When size of box is also factored in, then a small box can go low but
not loud, and vice-versa.

What all this distils down to, as far, again, as I recall, is that cost,
size, bass performance, sensitivity and maximum loudness are all
interrelated.

If I were in your position of having 80 watts available, this is
sufficient for quite high levels with 'speakers of average sensitivity
(say 86dB/watt) so I would choose on the basis of sound, size and cost.
Choosing very sensitive 'speakers (say 100dB/watt)could bring the
noise levels up to be noticeable and make the volume control very touchy.

S.

I was originally leaning toward speakers around 86db for that very
reason. I dont know if that is the right reason for choosing
sensitivity. My gut feeling is that it isn't although it may be
necessary.

wrote in message
oups.com...


** Groper road kill alert !!


I have an 80 wpc amp and am thinking of replacing my speakers.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.
Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?



** Two gentlemen in a nice white van are headed your way right now.

Sucker.......



........ Phil

Phil Allison wrote:
wrote in message
oups.com...


** Groper road kill alert !!


I have an 80 wpc amp and am thinking of replacing my speakers.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.
Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?



** Two gentlemen in a nice white van are headed your way right now.

Sucker.......



....... Phil


I wont be falling for that...

In article .com,
wrote:
I have an 80 wpc amp and am thinking of replacing my speakers.

The critical questions here would be:

1) What is the reason for wanting to replace your current speakers?

2) Can you get the sound levels you require with your current speakers, and
what is their nominal sensitivity?

If they play loud enough for you, then other speakers with similar
sensitivity and power handling should be fine. If they won't go loud
enough, then you may need either higher sensitivity, or/and more power.
Note, though that a change of 3dB won't sound like very much. You'd
probably need 10dB or more to make a dramatic difference.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.

Sensitivity tends to be involved in the trade-off between physical size and
bass extension. Although an expensive design might have a nasty input
impedance on the assumption that an expensive amp can handle this, there is
the risk that the owner won't do as expected. :-)

Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?

An amplifier will have a given ability to drive continuous levels, and a
given level to provide peaks. They have no 'preferences' as such. Most
music in my experience has peak/mean ratios of 10dB or more, which means
the continuous parts won't drop the peak level available much if the amp
has a decent PSU. (If it doesn't, don't buy it. :-) ) This said, given the
compression and clipping on some pop CDs. However if pop CDs are your main
music, then this might be a problem which could occur, but may not matter
much given the clipping already on the CD. :-/

The usual amplifier ratings will be for continuous use, and the chances are
that the peak levels will only be a couple of dB greater, which in
listening terms isn't very much. If 80Wpc isn't enough for you, then you'd
probably have to move to the order of 200Wpc or more to make a marked
difference. (Unless your amp has problems with something like current
limiting.)

FWIW In my experience in the UK most people with 'powerful' amps only
actually use them to output modest power levels. Although this will depend
on your taste in music and the size of your listening room. :-)

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Jim Lesurf wrote:
In article .com,
wrote:
I have an 80 wpc amp and am thinking of replacing my speakers.

The critical questions here would be:

1) What is the reason for wanting to replace your current speakers?

2) Can you get the sound levels you require with your current speakers, and
what is their nominal sensitivity?

If they play loud enough for you, then other speakers with similar
sensitivity and power handling should be fine. If they won't go loud
enough, then you may need either higher sensitivity, or/and more power.
Note, though that a change of 3dB won't sound like very much. You'd
probably need 10dB or more to make a dramatic difference.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.

Sensitivity tends to be involved in the trade-off between physical size and
bass extension. Although an expensive design might have a nasty input
impedance on the assumption that an expensive amp can handle this, there is
the risk that the owner won't do as expected. :-)

Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?

An amplifier will have a given ability to drive continuous levels, and a
given level to provide peaks. They have no 'preferences' as such. Most
music in my experience has peak/mean ratios of 10dB or more, which means
the continuous parts won't drop the peak level available much if the amp
has a decent PSU. (If it doesn't, don't buy it. :-) ) This said, given the
compression and clipping on some pop CDs. However if pop CDs are your main
music, then this might be a problem which could occur, but may not matter
much given the clipping already on the CD. :-/

The usual amplifier ratings will be for continuous use, and the chances are
that the peak levels will only be a couple of dB greater, which in
listening terms isn't very much. If 80Wpc isn't enough for you, then you'd
probably have to move to the order of 200Wpc or more to make a marked
difference. (Unless your amp has problems with something like current
limiting.)

FWIW In my experience in the UK most people with 'powerful' amps only
actually use them to output modest power levels. Although this will depend
on your taste in music and the size of your listening room. :-)

Slainte,

Jim


Answers:

1) They are a bit harsh. I want something that does not fatigue my ear
and if they are more revealing of the music then of course I would
appreciate that as well.

2) The sound levels are definately high enough and they are 90db
sensitivity. It would not bother me if the speakers were not capable
of such high volumes.

Its true I do use the amp at moderate levels and I did not buy the amp
first I had the speakers and another amp first. The first amp was warm
and fuzzy perhaps this is why the speakers did not sound harsh then.
But it was so long ago now that I dont remember. This amp is much more
detailed and enjoyable and I am very happy with the amp. I have
considered that changing the speaker might not be the right solution,
after all it does seem like a slippery slope of changing one component
after the other. But I am just thinking about it at the moment.

wrote:
I have an 80 wpc amp and am thinking of replacing my speakers.

With an 80W amp you don't have to worry. Buy speakers that you can live
with over the long term and your amp will no doubt drive them well.

In general, it is putting the cart before the horse to choose your amp
first and your speakers afterwards. Even in valves, where that happens
so often that the thoughtless can come to believe that choosing the amp
first is the correct procedure, it is counterproductive.

A couple of articles on my KISS netsite
http://members.lycos.co.uk/fiultra/KISS%20100.htm
KISS 102 by Andre Jute: The myth of the watt
KISS 103 by Andre Jute: Calculating the power our amp requires to drive
the chosen speakers
explain how little power you really require to drive even insensitive
speakers.

I had read that sensitivity is often compromised in higher end speakers
because higher end amps are often high wpc so can still drive them.

Too many speaker designers are slack incompetents who expect amp
designers to make up for their laziness and thoughtlessness; they run
after the pack and year after year turn out lowest common denominators
speakers.

Any overage is supposedly for transient spikes, an argument that
shortly leads to 2kW amps. I've had a couple of kW in amplification
power (12x 200W units where each pair bridged for 400W) for an outdoors
rock'n'roll poolside setup (it was built for me in 1969 by a couple of
chums from HP whose next invention was a heated brick in a fur wrap to
keep the feet of their departmental secretary warm) and we had to keep
a lock on the volume control and bribe the police and pay off the
neighbours within a three mile radius, and even then dogs and cats and
snakes went crazy and bit us, not to mention that the sound ****ed off
the piranhas I kept in my pool.

Although this sounds plausable I've also read that valve amps are ofter
low wpc. Besides dont amps prefer less work so they have more power in
reserve for fast transients?

I have valve amps from about a third of a watt to over eighty watts in
SE, and to over a hundred watt in PP. My squalid state amps run from
about ten watt to whatever a Quad 405 Mk II puts out (could be140W --
I've forgotten because it is an irrelevant number of importance only to
the marketing department). Besides the Quad which is permanently on and
might be switched in at any time, it is very rare for me to use an amp
of more than 20-25W, for the simple reason that that is enough to drive
anything to more than reasonable volumes. My everyday speakers are Quad
ESL-63 which are perhaps optimistically claimed to be 86dB/m sensitive.
That is, they are not very sensitive when compared to my Fidelio type
Lowther-driven horns at around 100dB/2m (only those who don't have
brains to put in gear measure a horn bigger than a tweeter at 1m)
in-box and 3dB better at least in-room. I drive the horns with an amp
of one third of a watt and shake the house with the bass by putting
them in the door of the top floor to use a four-story winding stairwell
as a horn-expansion and rooms on the way down as additional Helmholz
chambers; the treble goes up to 22kHz. You can see the horns and the
amp (a huge grey thing numbered Type 68 bis standing on its short end)
on my netsite via the URL under my sig. You can also see on the site
plans for very sensitive speakers (Impresario) I have designed for you
to build cheaply if you want to experiment with the sweetness of tone
available only in very low-powered valve amps. There are also some
cheaper ultrafi amps like the SEntry I designed for student use and
space.

Valve amps are in general more powerful than their bare ratings might
suggest. The ultrafidelista single-ended types (and quite a few PP
types as well if designed and built by the right people) operate in
Class A with maximum power permanently loaded and locked and ready to
rock'n'roll because they constantly draw a standing current even at
zero signal equal to maximum power, unlike your average solid state amp
which operates in class A/B if you're lucky, and doesn't come into real
power until it is well into Class B, that is, a Class B amp draws
current only when it is operating and then only proportional to output.
Compare the pressure in a water tank that starts full and (if correctly
choked and capped in the analogous power supply) stays at least
two-thirds full with one that starts empty and is replenished only to
the level of water drawn off (I could even argue that it is replenished
only to half the level of water drawn off, but that will just lead to a
nastiness with people who learned their engineering by rule of thumb
and have learned nothing since). The upshot is that in a valve/SS
comparison more is usually hidden than is illuminated. Valve/SS
comparisons are intrinsically unfair to SS even before you switch the
amplifiers on, and on switch-on become irremediably unfair unless cost
is an issue, which at our end of the audiophile spectrum it never is.
The same applies to comparisons of point source speakers, especially
dipoles to multi-driver boxes: the point sources and dipoles have an
intrinsic advantage in sonic quality over the multi-driver boxes, and
that advantage is multiplied when the multidriver box requires active
circuitry to do anything right.

Less is always more in the reproduction of music.

Just my opinion, of course. The majority has a perfect democratic right
to be wrong.

Duck!

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

Too many speaker designers are slack incompetents who expect amp
designers to make up for their laziness and thoughtlessness; they run
after the pack and year after year turn out lowest common denominators
speakers.

Lol, that sounds right.