Who fabricates 8 Ohms speakers...? I can't find other except Sony...

[Faustino Dina]

Hi,

I found good sales prices for Yamaha and Onkyo speakers, but it appear all
to have 6 Ohm impedance and I want to buy an AVR which specifies 8-16 Ohm
impedance. So which speaker fabricants have 8 Ohm speakers...? There is
something wrong with 8 Ohms speakers that it looks to be less than 8 Ohm
ones...?

Thanks in advance
Faustino

[Mark D. Zacharias]

A 6 ohm speaker effectively IS an 8 ohm speaker. They're just trying to be
more accurate in their rating. It just would not be a good idea to runs two
pairs at once on that receiver.

Mark Z.


"Shrivel" > wrote in message
...
> First of all, if the receiver can't reliably drive 6 ohms, I'm not sure
> you'd wanna look at it. That's usually an indication of very weak power
> supplies and amplification stages.
>
> Secondly, you're probably pretty safe still, even with 6 ohm speakers. If
> you choose 6 ohm speakers with good efficiency, I doubt you'll have much
> problem even with a receiver that only specifies 8 ohms. I probably
> wouldn't risk anything lower than that, though...
>
>
>
> "Faustino Dina" > wrote in message
> ...
> > Hi,
> >
> > I found good sales prices for Yamaha and Onkyo speakers, but it appear
all
> > to have 6 Ohm impedance and I want to buy an AVR which specifies 8-16
Ohm
> > impedance. So which speaker fabricants have 8 Ohm speakers...? There is
> > something wrong with 8 Ohms speakers that it looks to be less than 8 Ohm
> > ones...?
> >
> > Thanks in advance
> > Faustino
> >
> >
>
>
>

[Neil]

"Mark D. Zacharias" > wrote in message . net>...
> A 6 ohm speaker effectively IS an 8 ohm speaker.

I also wouldn't worry over 6 vs. 8 ohm. Shouldn't be a problem.

(BTW, the loudspeaker specs from manufacturers are often inaccurate,
and impedance will vary with frequencies also.)

>They're just trying to be
> more accurate in their rating. It just would not be a good idea to runs two
> pairs at once on that receiver.

Agree, unless the receiver manual states otherwise.

If I was using really low-impedance speakers (such as 2 ohms), I'd put
my hand on top of the receiver and make sure it's not getting too hot
and is well ventilated, especially when the receiver is turned up to
loud volume.

> Mark Z.
>
>
> "Shrivel" > wrote in message
> ...
> > First of all, if the receiver can't reliably drive 6 ohms, I'm not sure
> > you'd wanna look at it. That's usually an indication of very weak power
> > supplies and amplification stages.
> >
> > Secondly, you're probably pretty safe still, even with 6 ohm speakers. If
> > you choose 6 ohm speakers with good efficiency, I doubt you'll have much
> > problem even with a receiver that only specifies 8 ohms. I probably
> > wouldn't risk anything lower than that, though...
> >
> >
> >
> > "Faustino Dina" > wrote in message
> > ...
> > > Hi,
> > >
> > > I found good sales prices for Yamaha and Onkyo speakers, but it appear
> all
> > > to have 6 Ohm impedance and I want to buy an AVR which specifies 8-16
> Ohm
> > > impedance. So which speaker fabricants have 8 Ohm speakers...?

Almost all consumer speakers are specified as 8 ohms. See comments
above.

>>> There is
> > > something wrong with 8 Ohms speakers that it looks to be less than 8 Ohm
> > > ones...?
> > >
> > > Thanks in advance
> > > Faustino

[Kalman Rubinson]

On Thu, 17 Jul 2003 12:47:52 -0500, "Faustino Dina"
> wrote:

>"Shrivel" > wrote in message
...
>> First of all, if the receiver can't reliably drive 6 ohms, I'm not sure
>> you'd wanna look at it. That's usually an indication of very weak power
>> supplies and amplification stages.
>
>So you do not recommend a receiver who only drives 8 Ohm speakers...I'm
>right?

Not necessarily. If the unit is adequate for the speakers attached
and you do not have plans to change them with this particular
receiver, then an 8ohm-only receiver is OK. What the lack of a 4ohm
rating or application indicates is an inability to deliver power into
a lower impedance load usually as a result of cheaper power supplies
and output stages. Simply, you have to pay more to get more.

Kal

[Faustino Dina]

"Shrivel" > wrote in message
...
> First of all, if the receiver can't reliably drive 6 ohms, I'm not sure
> you'd wanna look at it. That's usually an indication of very weak power
> supplies and amplification stages.

So you do not recommend a receiver who only drives 8 Ohm speakers...I'm
right?

[Faustino Dina]

> I also wouldn't worry over 6 vs. 8 ohm. Shouldn't be a problem.
> (BTW, the loudspeaker specs from manufacturers are often inaccurate,
> and impedance will vary with frequencies also.)
> >They're just trying to be
> > more accurate in their rating. It just would not be a good idea to runs
two
> > pairs at once on that receiver.
>
> Agree, unless the receiver manual states otherwise.

The receiver is a Sony STR-DE685, the manual doesn't says anything about
speaker impedance except in the rear view of the receiver where is a label
below the speaker connectors that says to use 8-16 Ohms speakers.

> If I was using really low-impedance speakers (such as 2 ohms), I'd put
> my hand on top of the receiver and make sure it's not getting too hot
> and is well ventilated, especially when the receiver is turned up to
> loud volume.

So can I trust the 6 Ohm speakers will not melt my receiver as long as I
don't turn it too loud ? (Is anybody ready to put his sign under this... ;-)
?

[Mark D. Zacharias]

2 ohm operation would be a death sentence for many modern receivers' power
transformers, especially those which go to the trouble of spelling out 6 ohm
minimums on the rear panel. Denons especially are notorious for this, but
Pioneers and Yamahas are this way also.

Mark Z.



> If I was using really low-impedance speakers (such as 2 ohms), I'd put
> my hand on top of the receiver and make sure it's not getting too hot
> and is well ventilated, especially when the receiver is turned up to
> loud volume.


"Neil" > wrote in message
om...
> "Mark D. Zacharias" > wrote in message
. net>...
> > A 6 ohm speaker effectively IS an 8 ohm speaker.
>
> I also wouldn't worry over 6 vs. 8 ohm. Shouldn't be a problem.
>
> (BTW, the loudspeaker specs from manufacturers are often inaccurate,
> and impedance will vary with frequencies also.)
>
> >They're just trying to be
> > more accurate in their rating. It just would not be a good idea to runs
two
> > pairs at once on that receiver.
>
> Agree, unless the receiver manual states otherwise.
>
> If I was using really low-impedance speakers (such as 2 ohms), I'd put
> my hand on top of the receiver and make sure it's not getting too hot
> and is well ventilated, especially when the receiver is turned up to
> loud volume.
>
> > Mark Z.
> >
> >
> > "Shrivel" > wrote in message
> > ...
> > > First of all, if the receiver can't reliably drive 6 ohms, I'm not
sure
> > > you'd wanna look at it. That's usually an indication of very weak
power
> > > supplies and amplification stages.
> > >
> > > Secondly, you're probably pretty safe still, even with 6 ohm speakers.
If
> > > you choose 6 ohm speakers with good efficiency, I doubt you'll have
much
> > > problem even with a receiver that only specifies 8 ohms. I probably
> > > wouldn't risk anything lower than that, though...
> > >
> > >
> > >
> > > "Faustino Dina" > wrote in message
> > > ...
> > > > Hi,
> > > >
> > > > I found good sales prices for Yamaha and Onkyo speakers, but it
appear
> > all
> > > > to have 6 Ohm impedance and I want to buy an AVR which specifies
8-16
> > Ohm
> > > > impedance. So which speaker fabricants have 8 Ohm speakers...?
>
> Almost all consumer speakers are specified as 8 ohms. See comments
> above.
>
> >>> There is
> > > > something wrong with 8 Ohms speakers that it looks to be less than 8
Ohm
> > > > ones...?
> > > >
> > > > Thanks in advance
> > > > Faustino
>

[Mark D. Zacharias]

6 ohm speakers are fine. The big thing is just to use some common sense when
operating them. Watch out for too much volume, for too long, and avoid
excessive tone / EQ settings. This is doubly true of lower impedance or
parallel speaker operation.

Mark Z.


"Faustino Dina" > wrote in message
...
> > I also wouldn't worry over 6 vs. 8 ohm. Shouldn't be a problem.
> > (BTW, the loudspeaker specs from manufacturers are often inaccurate,
> > and impedance will vary with frequencies also.)
> > >They're just trying to be
> > > more accurate in their rating. It just would not be a good idea to
runs
> two
> > > pairs at once on that receiver.
> >
> > Agree, unless the receiver manual states otherwise.
>
> The receiver is a Sony STR-DE685, the manual doesn't says anything about
> speaker impedance except in the rear view of the receiver where is a label
> below the speaker connectors that says to use 8-16 Ohms speakers.
>
> > If I was using really low-impedance speakers (such as 2 ohms), I'd put
> > my hand on top of the receiver and make sure it's not getting too hot
> > and is well ventilated, especially when the receiver is turned up to
> > loud volume.
>
> So can I trust the 6 Ohm speakers will not melt my receiver as long as I
> don't turn it too loud ? (Is anybody ready to put his sign under this...
;-)
> ?
>
>
>

[Shrivel]

"Kalman Rubinson" > wrote in message
...
> On Thu, 17 Jul 2003 12:47:52 -0500, "Faustino Dina"
> > wrote:
>
> >"Shrivel" > wrote in message
> ...
> >> First of all, if the receiver can't reliably drive 6 ohms, I'm not sure
> >> you'd wanna look at it. That's usually an indication of very weak
power
> >> supplies and amplification stages.
> >
> >So you do not recommend a receiver who only drives 8 Ohm speakers...I'm
> >right?
>
> Not necessarily. If the unit is adequate for the speakers attached
> and you do not have plans to change them with this particular
> receiver, then an 8ohm-only receiver is OK. What the lack of a 4ohm
> rating or application indicates is an inability to deliver power into
> a lower impedance load usually as a result of cheaper power supplies
> and output stages. Simply, you have to pay more to get more.
>
> Kal

Yeah... what he said... ;-)

In all seriousness, if I were serious about sound quality and assuming I
could afford something more than the cheapest receivers, I'd spend a little
more and get a receiver that was rated at a minimum of 4 ohms, and insure
that pretty much any except the most demanding speakers could be driven
without clipping or burning up the receiver. But that's just me and we may
not have the same pocketbooks or desires...

I'm also not a huge fan of most Sony stuff either, but that's only because
I've simply been burned by Sony equiptment too many times in the past and
I've learned my lesson.

If you're just getting into home theater, I'm sure whatever you choose will
be a treat. Enjoy it and don't worry too much about the 6 and 8 ohm
difference.

[GregS]

In article . net>, "Mark D. Zacharias" > wrote:
>A 6 ohm speaker effectively IS an 8 ohm speaker. They're just trying to be
>more accurate in their rating. It just would not be a good idea to runs two
>pairs at once on that receiver.

If its rated 6 ohms then its rated 6 ohms nominal. Its what the manufacturer came up with.
Many speakers are rated at the MINIMUM impedance, not always nominal.
When I make a speaker, the impedance is essentialy the measured DC resistance.
Unless I buy some of those Pioneer 6 ohm drivers, then its impossible for me to go
lower than 8 ohms unless I go down to 4.

greg

[Faustino Dina]

> I've simply been burned by Sony equiptment too many times in the past and
> I've learned my lesson.
What do you mean when say "burned"...? Sorry, my english is not good enought
for tasting this phrase, I'm taking it literally.... ;-)

> If you're just getting into home theater, I'm sure whatever you choose
will
> be a treat. Enjoy it and don't worry too much about the 6 and 8 ohm
> difference.
I'm new to HiFi, then I'm looking for cheap, entry level, equipment, for
training my ears. I'm aiming to the home cinema package from Sony because it
includes speakers, subwoofer and receiver for the price of one receiver of
another HiFi firms (ok, it's looking the Mexican market where prices are two
or three times the USA --where is the globalization? ). But I'm looking also
for two good speakers for stereo playing. I don't trust the small speakers
that comes with the home-cinema pack....

[Neil]

"Faustino Dina" > wrote in message >...
> > I also wouldn't worry over 6 vs. 8 ohm. Shouldn't be a problem.
> > (BTW, the loudspeaker specs from manufacturers are often inaccurate,
> > and impedance will vary with frequencies also.)
> > >They're just trying to be
> > > more accurate in their rating. It just would not be a good idea to runs
> two
> > > pairs at once on that receiver.
> >
> > Agree, unless the receiver manual states otherwise.
>
> The receiver is a Sony STR-DE685, the manual doesn't says anything about
> speaker impedance except in the rear view of the receiver where is a label
> below the speaker connectors that says to use 8-16 Ohms speakers.

Then speakers of 8-16 ohms should be fine, and I also think that 6
ohms is close enough to be OK and not cause your receiver to overheat.
You ahould make sure your receiver is well ventilated, no matter what
speakers you use. There should be at least a few inches of space above
your receiver so that air can circulate and the receiver doesn't
overheat.

BTW, Consumer Reports magazine (www.consumerreports.org) tests reviews
receivers. CR tests whether receiver will perform acceptably at 4, 8,
and 16 ohms. Last November, CR printed a review that includes your
receiver. CR recommended against using 4 ohm speakers with almost all
the receivers tested, including yours. So just in case you ever are
considering 4 ohm speakers, you probably shouldn't use those.

> > If I was using really low-impedance speakers (such as 2 ohms), I'd put
> > my hand on top of the receiver and make sure it's not getting too hot
> > and is well ventilated, especially when the receiver is turned up to
> > loud volume.
>
> So can I trust the 6 Ohm speakers will not melt my receiver as long as I
> don't turn it too loud ? (Is anybody ready to put his sign under this... ;-)

I think you'll be OK. But when you start using the 6 ohm speakers,
just put your hand on top of the receiver occasionally and make sure
the receiver doesn't feel hot. (It's normal for a receiver or amp to
feel warm, but if it feels hot, that's a sign of trouble.)

Also, just out of curiousity, I wonder if your Sony receiver has a
built-in cooling fan? That can also help, although the fan may
contribute some noise. Modern Dolby receivers have so many amps and
electronics built in that some of these receivers now include fans to
help cool the receiver.

(BTW, many years ago when I didn't know better, I once installed a
reciever in some bookshelves and put one bookshelf right on top of a
receiver, blocking the receiver's cooling vents. Eventually the
receiver failed and required service, the technician told me the
receiver had overheated, he repaired it, and I learned my lesson about
making sure receivers and amps get enough ventilation. Another BTW:
that happened 25-30 years ago, and thanks to luck and ventilation,
that receiver is still working now.)

[Faustino Dina]

> I travel all throughout Mexico frequently, and I am amazed on how
expensive
> electronic equipment is. Why is this?

My first I suspect is the government. Mexico is well known to be a country
with a lot of tax evasion. Then the gov raises the taxes so we, the one few
good citicens, pay the taxes they are unable to collect...

But I also found that internet sellers in USA don't want to export many
items, specially HiFi audio equipment. I read in some sites it's 'cause the
manufacturer doesn't permits to do so. Adding that the market for HiFi in
Mexico is inherently weaker than in developed countries, then it is hard to
find well stocked distributors....So where is the world markets?, where is
the globalization...? Sony has a solid presence in Mexico, I can buy
directly from him and make valid my guarantee on many places across the
country, but others HiFi firms are accesible only through not so convincent
dealers....

[Shrivel]

"Faustino Dina" > wrote in message
...
> > I've simply been burned by Sony equiptment too many times in the past
and
> > I've learned my lesson.
> What do you mean when say "burned"...? Sorry, my english is not good
enought
> for tasting this phrase, I'm taking it literally.... ;-)

I mean that in my years of buying audio and video equipment, the Sony stuff
has ALWAYS proven to be the least reliable. I've had ONE single piece of
Sony stuff that did not die prematurely and that is my Sony EP9ES surround
processor and I attribute it's longevity to the fact that it's an "ES"
component, which means it's built by an entirely different division of Sony.
The other stuff that has broken:

2 car stereo head units
1 Laserdisc player
1 CD player
1 receiver


I can only think of ONE SINGLE piece of A/V equipment that was not Sony
branded that has broken on me in all those years and that is an NEC
integrated amplifier.

Needless to say, I don't buy Sony anymore, although I never really had any
complaints about the sound or video with any of the products. The lack of
reliability was the problem.

[Geoff Wood]

"Faustino Dina" > wrote in message
...
> Hi,
>
> I found good sales prices for Yamaha and Onkyo speakers, but it appear all
> to have 6 Ohm impedance and I want to buy an AVR which specifies 8-16 Ohm
> impedance. So which speaker fabricants have 8 Ohm speakers...? There is
> something wrong with 8 Ohms speakers that it looks to be less than 8 Ohm
> ones...?

Zillions of companies make speakers that would suite. 6 ohms should not be a
problem - 8Ohms is a pretty nominal figure at the best of times.

Other brands - try looking in a hifi shop rather than a department store.


geoff

[Geoff Wood]

"Mark D. Zacharias" > wrote in message
link.net...
> Simply not true. Speakers were rated at a "nominal" 8 ohms for decades but
> they actually measured closer to 5 or 6. Nowadays the trend is to rate the
> EXACT SAME SPEAKER type at 6 ohms instead of 8.

You talking impedence or resistance ?


geoff

[Geoff Wood]

"Faustino Dina" > wrote in message news:bf9bq0
> I'm new to HiFi, then I'm looking for cheap, entry level, equipment, for
> training my ears. I'm aiming to the home cinema package from Sony because
it
> includes speakers, subwoofer and receiver for the price of one receiver of
> another HiFi firms (ok, it's looking the Mexican market where prices are
two
> or three times the USA --where is the globalization? ). But I'm looking
also
> for two good speakers for stereo playing. I don't trust the small speakers
> that comes with the home-cinema pack....
>

Just don't get anything with silver plastic on the cabinet !

;-)


geoff

[Mark D. Zacharias]

I think we're really splitting hairs here. I'm out of this one.

mz


"GregS" > wrote in message
...
> In article . net>, "Mark
D. Zacharias" > wrote:
> >A 6 ohm speaker effectively IS an 8 ohm speaker. They're just trying to
be
> >more accurate in their rating. It just would not be a good idea to runs
two
> >pairs at once on that receiver.
>
> If its rated 6 ohms then its rated 6 ohms nominal. Its what the
manufacturer came up with.
> Many speakers are rated at the MINIMUM impedance, not always nominal.
> When I make a speaker, the impedance is essentialy the measured DC
resistance.
> Unless I buy some of those Pioneer 6 ohm drivers, then its impossible for
me to go
> lower than 8 ohms unless I go down to 4.
>
> greg
>

[Faustino Dina]

> 2 car stereo head units
> 1 Laserdisc player
> 1 CD player
> 1 receiver

....yeah, it's really a very convincent list, I was understanding the word
"burned" correctly... :-(

> Needless to say, I don't buy Sony anymore, although I never really had any
> complaints about the sound or video with any of the products. The lack of
> reliability was the problem.

Thanks for your advice, I'll consider my decision...

[Leadfoot]

> The receiver is a Sony STR-DE685, the manual doesn't says anything about
> speaker impedance except in the rear view of the receiver where is a label
> below the speaker connectors that says to use 8-16 Ohms speakers.
>


I ran a Sony @100WPC STR-DE575 running 4 ohm Cerwin-Vega RE-30's for at
least 6 months. Mostly I used them for Home theather and some music and
rarely cranked them I recently upgraded to a Yamaha RX-V630 that while
rated @80WPC is much louder than the Sony. Part of the reason for the
upgrade to the Yamaha was the 4 ohm/8 ohm switch.

I don't think the 6 ohm speaker will pose a problem so long as you don't
crank up the volume for LONG periods of time and you make sure the Sony's
air vents are kept open. If you have a situation where you do want to crank
the volume for long periods of time you could place a fan near the air vents
to keep the air in the receiver circulating.

[ST]

The Amplifier failing is the lest of your problems, since the speakers are
being grossly underpowered it will cause the amp to clip, especially when
producing loud (dynamic) bursts.

You will eventually damage the speakers!

NOT leaving the amp running for long durations and cooling it is a waste of
time. The amp will not be damaged but again, your speakers will.



"Leadfoot" > wrote in message
news:TyCSa.13944$u51.11838@fed1read05...
>
> > The receiver is a Sony STR-DE685, the manual doesn't says anything
about
> > speaker impedance except in the rear view of the receiver where is a
label
> > below the speaker connectors that says to use 8-16 Ohms speakers.
> >
>
>
> I ran a Sony @100WPC STR-DE575 running 4 ohm Cerwin-Vega RE-30's for at
> least 6 months. Mostly I used them for Home theather and some music and
> rarely cranked them I recently upgraded to a Yamaha RX-V630 that while
> rated @80WPC is much louder than the Sony. Part of the reason for the
> upgrade to the Yamaha was the 4 ohm/8 ohm switch.
>
> I don't think the 6 ohm speaker will pose a problem so long as you don't
> crank up the volume for LONG periods of time and you make sure the Sony's
> air vents are kept open. If you have a situation where you do want to
crank
> the volume for long periods of time you could place a fan near the air
vents
> to keep the air in the receiver circulating.
>
>

[michael Mueller]

Hello All. I've been lurking for a while in the group and find it
interesting. As for this post if I may?
Why go cheap to get your ears adjusted to good equipment? That seems
very counter productive. Look for some good used equipment on the net.
Buy a good pair of new speakers, a good used higher end amp amp. and a
new Digital source. NAD makes an excellent line of CD players.
I have a sony ES CD player that I am still using after 13 years. It
still works well.

I recently upgarded to a Rega Jupiter. I replaced an old Philips 312
turntable 6 months ago with MMF5 table. All this goes through a Fisher
400c preamp or a Heathkit SP-2A preamp. The system is tri-amped with 2
Dynaco MKIII's and a Dynaco ST-70.

Speakers are LYnn Olsens Ariels Version 3. All the tube gear has been
rebuilt over the last 4 years
Thank you for your time
Mike Mueller

[Tom Steele]

"Shrivel" > wrote in message
...
>
> I mean that in my years of buying audio and video equipment, the Sony
stuff
> has ALWAYS proven to be the least reliable. I've had ONE single piece of
> Sony stuff that did not die prematurely and that is my Sony EP9ES surround
> processor and I attribute it's longevity to the fact that it's an "ES"
> component, which means it's built by an entirely different division of
Sony.
> The other stuff that has broken:
>
> 2 car stereo head units
> 1 Laserdisc player
> 1 CD player
> 1 receiver
>
>
> I can only think of ONE SINGLE piece of A/V equipment that was not Sony
> branded that has broken on me in all those years and that is an NEC
> integrated amplifier.
>
> Needless to say, I don't buy Sony anymore, although I never really had any
> complaints about the sound or video with any of the products. The lack of
> reliability was the problem.

I found that interesting to read on my Sony Multiscan 20 se II monitor that
I purchased in ~1994. It has been my monitor through several computers and
several different iterations of the Intel Pentium series processor.

Over my shoulder is my Sony XBR32 TV which was also purchased around 10
years ago. It is STILL a very respectable TV and would cost ~$1,000+ to
replace with a similar quality/featured TV today.

I could go on. I guess everyone's experiences are different.

Sincerely,

TS

[[email protected]]

Every year or two CU tests popular speakers, and while most speakers
claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
opinions should to be taken with a grain of salt, measurements are
measurments, and not opinions.

[R]

wrote in news:1102953201.277311.196100
@c13g2000cwb.googlegroups.com:

> Every year or two CU tests popular speakers, and while most speakers
> claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
> opinions should to be taken with a grain of salt, measurements are
> measurments, and not opinions.
>
>

CU is as a disreputable source as I can think of bar none. I would take
anything they say with several large truckloads of salt and a shovel. The
shovel is to dig out from under all the manure they dump on the reader.

r


--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.

[TonyP]

wrote in news:1102953201.277311.196100
> @c13g2000cwb.googlegroups.com:
> Every year or two CU tests popular speakers, and while most speakers
> claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
> opinions should to be taken with a grain of salt, measurements are
> measurments, and not opinions.

The good thing about speaker impedance is that you can quote almost any
figure you like, and be able to back it up with measurements. Unfortunately
the frequency at which that figure applies is never quoted.

CU are probably right if they are talking about minimum impedance, however
the only *useful* measurement is an impedance Vs frequency graph, then you
can decide for yourself what is relevant.

TonyP.

[[email protected]]

Julian Hirsch of Stereo Review fame/notorietyconsidered CU a valuable
source of consumer audio info , although not the last word. He also
believed they had great testing facilities, and the requisite, unbiased
audiophile testers. Of course, some folks considered Hirsch to be
disreputable, but I, along with countless others, didn't; quite the
opposite.

[Engineer]

> wrote in message
oups.com...
> Every year or two CU tests popular speakers, and while most speakers
> claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
> opinions should to be taken with a grain of salt, measurements are
> measurments, and not opinions.
>
I don't read CU so I can't comment on their alleged "4 ohm" claim.
However, the key word is "nominal" that should precede "8 ohms".
Another point is minimum impedance. Nominally 8 ohms speakers can go
as low as 4 ohms at some frequencies, putting a bit of a strain on
cheap amplifiers that can't deliver the required current. Ideally,
you need the whole impedance vs. frequency graph, complete with phase
angle.
Cheers.
Roger

[r.berger]

"Engineer" > schreef in bericht
...
> > wrote in message
> oups.com...
> > Every year or two CU tests popular speakers, and while most speakers
> > claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
> > opinions should to be taken with a grain of salt, measurements are
> > measurments, and not opinions.
> >
> I don't read CU so I can't comment on their alleged "4 ohm" claim.
> However, the key word is "nominal" that should precede "8 ohms".
> Another point is minimum impedance. Nominally 8 ohms speakers can go
> as low as 4 ohms at some frequencies, putting a bit of a strain on
> cheap amplifiers that can't deliver the required current. Ideally,
> you need the whole impedance vs. frequency graph, complete with phase
> angle.
According to DIN standardisation the minimum impedance is 0.8 x nominal
impedance or the nominal impedance is 1.25 x the minimum impedance.
Consequently a speaker with a nominal impedance of 8 Ohm will have a minimum
impedance not lower than 6.4 Ohm and a 4 Ohm speaker 3.2 Ohm. Thus a speaker
with a minimum impedance of 4 Ohm has a nominal impedance of 1.25 x 4 Ohm =
5 Ohm and could never be an 8 Ohm speaker (according to DIN).
Ronald Berger

[Richard Crowley]

spironical wrote ...
> Every year or two CU tests popular speakers, and while most speakers claim
> to be 8 ohms, CU finds most to measure 4 ohms. Although CU's opinions
> should to be taken with a grain of salt, measurements are measurments, and
> not opinions.

"8 ohms" sounds like the "nominal rating". While the speaker is
likely actually 8 ohms at some point, the impedance is never
uniform across the whole frequency spectrum. Nominal ratings
are just a guide to tell you what the design impedance was.

CU's measurement of 4 ohms sounds like the minimum impedance
at some (unspecified) frequency. This seems normal to me. Look
at any impedance curve and you can see that the variation between
minimum and maximum impedance can sometimes be 2x or even 4x.

The fact that CU is reporting the minimum impedance (without any
apparent explanation or context) is just indicative of their questionable
understanding, judgement, and reliability in technical areas.

No offense, but the notion that "measurements are measurements
not opinions" is not a safe world-view to subscribe to. ALWAYS
question how the measurements were made and what is the hidden
agenda of the person reporting them. In CU's case, reporting 4 ohms
for nominally-rated 8 ohm speakers makes them look like consumer
champions giving you valuable information worth paying for. While
in reality, they are reporting perfectly normal phenomenon.

[r.berger]

"Richard Crowley" > schreef in bericht
...
> spironical wrote ...
> > Every year or two CU tests popular speakers, and while most speakers
claim
> > to be 8 ohms, CU finds most to measure 4 ohms. Although CU's opinions
> > should to be taken with a grain of salt, measurements are measurments,
and
> > not opinions.
>
> "8 ohms" sounds like the "nominal rating". While the speaker is
> likely actually 8 ohms at some point, the impedance is never
> uniform across the whole frequency spectrum. Nominal ratings
> are just a guide to tell you what the design impedance was.
>
> CU's measurement of 4 ohms sounds like the minimum impedance
> at some (unspecified) frequency. This seems normal to me. Look
> at any impedance curve and you can see that the variation between
> minimum and maximum impedance can sometimes be 2x or even 4x.

Or much more, according measurements I have taken.

> The fact that CU is reporting the minimum impedance (without any
> apparent explanation or context) is just indicative of their questionable
> understanding, judgement, and reliability in technical areas.
>
> No offense, but the notion that "measurements are measurements
> not opinions" is not a safe world-view to subscribe to. ALWAYS
> question how the measurements were made and what is the hidden
> agenda of the person reporting them. In CU's case, reporting 4 ohms
> for nominally-rated 8 ohm speakers makes them look like consumer
> champions giving you valuable information worth paying for. While
> in reality, they are reporting perfectly normal phenomenon.
>

I don't know CU but to me the minimum impedance is much more important than
the (fake) nominal impedances the brands state. Because along with the
electrical phase behaviour, this is one of the most important indications of
how difficult the speaker load will be for the (power/integrated)amplifier.
Many tube amplyfiers with very low damping factors in particular, the Audio
Note single ended amplifiers for instance, can be very sensitive for hefty
impedance curves with very low dips and tall highs. They will audibly affect
the frequency curve. High impedances are an easy load for tube amplifiers
and semi-conductor amplifiers as wel. I always try to design the minimum
impedance as high as possible. In my opinion it sounds better on many
amplifiers, including semi-conductor amplifiers.
Ronald Berger

[Wylie Williams]

wrote:
> Every year or two CU tests popular speakers, and while most speakers
> claim to be 8 ohms, CU finds most to measure 4 ohms. Although CU's
> opinions should to be taken with a grain of salt, measurements are
> measurments, and not opinions.
>


Was there any particular reason why this subject arose?

Wylie Williams

[TonyP]

"r.berger" > wrote in message
...
> According to DIN standardisation the minimum impedance is 0.8 x nominal
> impedance or the nominal impedance is 1.25 x the minimum impedance.
> Consequently a speaker with a nominal impedance of 8 Ohm will have a
minimum
> impedance not lower than 6.4 Ohm and a 4 Ohm speaker 3.2 Ohm. Thus a
speaker
> with a minimum impedance of 4 Ohm has a nominal impedance of 1.25 x 4 Ohm
=
> 5 Ohm and could never be an 8 Ohm speaker (according to DIN).

Unfortunately I can't remember the last time I saw a speaker impedance
quoted according to DIN spec.
Maybe in Europe?

TonyP.

[r.berger]

"TonyP" > schreef in bericht
...
>
> "r.berger" > wrote in message
> ...
> > According to DIN standardisation the minimum impedance is 0.8 x nominal
> > impedance or the nominal impedance is 1.25 x the minimum impedance.
> > Consequently a speaker with a nominal impedance of 8 Ohm will have a
> minimum
> > impedance not lower than 6.4 Ohm and a 4 Ohm speaker 3.2 Ohm. Thus a
> speaker
> > with a minimum impedance of 4 Ohm has a nominal impedance of 1.25 x 4
Ohm
> =
> > 5 Ohm and could never be an 8 Ohm speaker (according to DIN).
>
> Unfortunately I can't remember the last time I saw a speaker impedance
> quoted according to DIN spec.
> Maybe in Europe?

Yes, that is right.
The DIN standardisation for the nominal and minimum impedance is commonly
used in the European Union. But there are brands who apparently have their
"own
standards" which seem to vary to fit the design of the speaker. They seem to
think flattery will get them everywhere.
Most experienced European audio reviewers disapprove of this behaviour.
People who
know about this fiddling with figures experience it as misleading.
Ronald Berger.

[[email protected]]

While slightly o/t, the subject is related to the nature of
manufacturer's published, and measured speaker resistance specs. It's
just a question of which, if any, specs to take seriously. Personally,
I just hook up the speakers, and if the amp gets too hot at normal
levels, the speakers go back.

[r.berger]

> schreef in bericht
oups.com...
> While slightly o/t, the subject is related to the nature of
> manufacturer's published, and measured speaker resistance specs. It's
> just a question of which, if any, specs to take seriously. Personally,
> I just hook up the speakers, and if the amp gets too hot at normal
> levels, the speakers go back.
>
If you knew the minimum impedance you would'nt have bought them at all
and you wouldn't have run the risk of damaging (blowing up) your amplifier.
Ronald Berger

[r.berger]

> schreef in bericht
oups.com...
> While slightly o/t, the subject is related to the nature of
> manufacturer's published, and measured speaker resistance specs. It's
> just a question of which, if any, specs to take seriously. Personally,
> I just hook up the speakers, and if the amp gets too hot at normal
> levels, the speakers go back.
>
If you knew the minimum impedance you would'nt have bought them at all
and you wouldn't have run the risk of damaging (blowing up) your amplifier.
Ronald Berger

[r.berger]

> schreef in bericht
oups.com...
> While slightly o/t, the subject is related to the nature of
> manufacturer's published, and measured speaker resistance specs. It's
> just a question of which, if any, specs to take seriously. Personally,
> I just hook up the speakers, and if the amp gets too hot at normal
> levels, the speakers go back.
>
If you knew the minimum impedance you would'nt have bought them at all
and you wouldn't have run the risk of damaging (blowing up) your amplifier.
Ronald Berger

[r.berger]

> schreef in bericht
oups.com...
> While slightly o/t, the subject is related to the nature of
> manufacturer's published, and measured speaker resistance specs. It's
> just a question of which, if any, specs to take seriously. Personally,
> I just hook up the speakers, and if the amp gets too hot at normal
> levels, the speakers go back.
>
If you knew the minimum impedance you would'nt have bought them at all
and you wouldn't have run the risk of damaging (blowing up) your amplifier.
Ronald Berger

[r.berger]

> schreef in bericht
oups.com...
> While slightly o/t, the subject is related to the nature of
> manufacturer's published, and measured speaker resistance specs. It's
> just a question of which, if any, specs to take seriously. Personally,
> I just hook up the speakers, and if the amp gets too hot at normal
> levels, the speakers go back.
>
If you knew the minimum impedance you would'nt have bought them at all
and you wouldn't have run the risk of damaging (blowing up) your amplifier.
Ronald Berger

[TonyP]

"Richard Crowley" > wrote in message
...
> CU's measurement of 4 ohms sounds like the minimum impedance
> at some (unspecified) frequency. This seems normal to me. Look
> at any impedance curve and you can see that the variation between
> minimum and maximum impedance can sometimes be 2x or even 4x.

Or 10x!.

> The fact that CU is reporting the minimum impedance (without any
> apparent explanation or context) is just indicative of their questionable
> understanding, judgement, and reliability in technical areas.

Very true.

> No offense, but the notion that "measurements are measurements
> not opinions" is not a safe world-view to subscribe to.

It's quite correct. It's when you are basing an opinion on questionable
measurements that problems arise.
Only when you know exactly what is being measured, and the uncertainty of
those measurements, is it is possible to arrive at a valid conclusion.

> ALWAYS
> question how the measurements were made and what is the hidden
> agenda of the person reporting them. In CU's case, reporting 4 ohms
> for nominally-rated 8 ohm speakers makes them look like consumer
> champions giving you valuable information worth paying for.

Well spotted.:-)

TonyP.