Low noise resistors

[Don]

Archived from groups: rec.audio.tech (More info?)

Is it better to use over rated (higher wattage) resistors for low noise, or
just enough wattage capability to cover expected conditions plus a little
more for safty ?

My thinking is that over rating will result in cooler resistors, so therefore,
less noise, but, on the otherhand, more material for the signal to pass
through, therefore, more noise.
-Don

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

In article <uyxqc.74473$536.12094292@attbi_s03>,
TAKE-OUTdobrien25@comcast.net (Don) wrote:

> Is it better to use over rated (higher wattage) resistors for low noise, or
> just enough wattage capability to cover expected conditions plus a little
> more for safty ?
>
> My thinking is that over rating will result in cooler resistors, so
> therefore,
> less noise, but, on the otherhand, more material for the signal to pass
> through, therefore, more noise.

The noise is not due to heating, There are two sources of noise in
resistors, thermal noise and "excess noise". Thermal noise is a function
of temperature and resistance, and nothing you (or the manufacturer) can
do will alter it.

Excess noise is material and process dependent. If it matters ( and most
times it does not), the proper solution is to select "low noise"
resistors. In general, carbon resistors are worse than metal film, are
worse than bulk metal.

Isaac

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

>Is it better to use over rated (higher wattage) resistors for low noise, or
>just enough wattage capability to cover expected conditions plus a little
>more for safty ?
>
>My thinking is that over rating will result in cooler resistors, so therefore,
>less noise, but, on the otherhand, more material for the signal to pass
>through, therefore, more noise.

First thing would be to make sure that the resistors are adequately
de-rated to survive properly! Years ago, one of the early-generation
high-power transistor amps (the "Tigersaurus") developed a bad
reputation for failing after some period of use. It turned out that
the output stage used a "bias stack" of resistors, which were using
relatively small parts (1/2 watt?) but actually were dissipating
several times their rated amount of power. They cooked, and the amp
had a tendency to suffer thermal runaway, oscillate, burst into flames
(literally), or exhibit other forms of makes-the-owner-really-nervous
misbehavior.

So, I'd certainly recommend de-rating all resistors conservatively, to
ensure long life. Running 'em at no more than 50% of rated
dissipation would probably not be a bad thing.

As to noise, though, I don't think it's a terribly big issue in any
well-designed preamp. The primary noise source in a resistor is
thermal or Johnson noise: the noise power is proportional to absolute
temperature, and a matter of a few degrees of heating around room
temperature isn't going to make a big difference. The noise voltage
across the resistor is a function of the noise power and the
resistance... the amount of material used to make up this resistance
doesn't appear to enter into it. As long as you're using good-quality
resistors (e.g. decent metal-film ones), a 1-watter ought to have the
same amount of thermal noise as a 1/8-watter, at the same temperature.

I don't know whether the size/rating of the resistor has any effect on
the quantity of excess (non-thermal) noise, but this ought to be *way*
down in the weeds if you're using good-quality film resistors.

In short, I wouldn't worry about it.

--
Dave Platt <dplatt@radagast.org> AE6EO
Hosting the Jade Warrior home page: http/www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

"Isaac Wingfield" <isw@witzend.com> wrote in message
news:isw-301A53.19580318052004@netnews.comcast.net...
> The noise is not due to heating, There are two sources of noise in
> resistors, thermal noise and "excess noise". Thermal noise is a function
> of temperature and resistance, and nothing you (or the manufacturer) can
> do will alter it.

Saying thermal noise is not due to heating, is a bit of a misnomer. Sure
there will always be thermal noise at any temperature above absolute zero,
but heating will obviously increse the temperature and hence the noise

TonyP.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

TonyP wrote:
> "Isaac Wingfield" <isw@witzend.com> wrote in message
> news:isw-301A53.19580318052004@netnews.comcast.net...
>> The noise is not due to heating, There are two sources of noise in
>> resistors, thermal noise and "excess noise". Thermal noise is a
>> function of temperature and resistance, and nothing you (or the
>> manufacturer) can do will alter it.
>
> Saying thermal noise is not due to heating, is a bit of a misnomer.
> Sure there will always be thermal noise at any temperature above
> absolute zero, but heating will obviously increse the temperature and
> hence the noise

Long ago I was building (tubed) RIAA preamps. I had a goodly collection of
small precision wirewound resistors at my disposal, so I built a stereo
preamp made up of them. The difference in noise levels, compared to carbon
compostiion resistors, was negligable.

Some time later I was building transistorized RIAA preamps, but this time
the comparison was between carbon film resistors and deposited metal
resistors. Similar results.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:7_mdnb24x5fb_jbdRVn-sQ@comcast.com...
> TonyP wrote:
> > Saying thermal noise is not due to heating, is a bit of a misnomer.
> > Sure there will always be thermal noise at any temperature above
> > absolute zero, but heating will obviously increse the temperature and
> > hence the noise

> Long ago I was building (tubed) RIAA preamps. I had a goodly collection of
> small precision wirewound resistors at my disposal, so I built a stereo
> preamp made up of them. The difference in noise levels, compared to carbon
> compostiion resistors, was negligable.
> Some time later I was building transistorized RIAA preamps, but this time
> the comparison was between carbon film resistors and deposited metal
> resistors. Similar results.

Yes but has nothing to do with temperature. Not that I was suggesting large
differences, just that physics dictates an increase.
As for the reliability of carbon resistors, put your money on the metal
The carbon WILL become more noisy at some stage.

TonyP.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

"TonyP" <TonyP@optus.net.com.au> wrote in message
news:40ab893a$0$1588$afc38c87@news.optusnet.com.au...
>
> "Arny Krueger" <arnyk@hotpop.com> wrote in message
> news:7_mdnb24x5fb_jbdRVn-sQ@comcast.com...
> > TonyP wrote:
> > > Saying thermal noise is not due to heating, is a bit of a
misnomer.
> > > Sure there will always be thermal noise at any temperature above
> > > absolute zero, but heating will obviously increse the
temperature and
> > > hence the noise
>
> > Long ago I was building (tubed) RIAA preamps. I had a goodly
collection of
> > small precision wirewound resistors at my disposal, so I built a
stereo
> > preamp made up of them. The difference in noise levels, compared
to carbon
> > compostiion resistors, was negligable.
> > Some time later I was building transistorized RIAA preamps, but
this time
> > the comparison was between carbon film resistors and deposited
metal
> > resistors. Similar results.
>
> Yes but has nothing to do with temperature. Not that I was
suggesting large
> differences, just that physics dictates an increase.
> As for the reliability of carbon resistors, put your money on the
metal
> The carbon WILL become more noisy at some stage.

The thermal noise of all resistances is the same: kTB. The answer
is in watts. If there is current flowing through the resistor, there
will be additional noise, the amount and spectral charateristics of
which are wildly different. I've found that bulk metal resistors have
the least added noise, followed by metal film. The larger the
resistor, the quieter it is wrt the excess noise.

Norm Strong

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

In article <40ab5fb3$0$1587$afc38c87@news.optusnet.com.au>,
"TonyP" <TonyP@optus.net.com.au> wrote:

> "Isaac Wingfield" <isw@witzend.com> wrote in message
> news:isw-301A53.19580318052004@netnews.comcast.net...
> > The noise is not due to heating, There are two sources of noise in
> > resistors, thermal noise and "excess noise". Thermal noise is a function
> > of temperature and resistance, and nothing you (or the manufacturer) can
> > do will alter it.
>
> Saying thermal noise is not due to heating, is a bit of a misnomer. Sure
> there will always be thermal noise at any temperature above absolute zero,
> but heating will obviously increse the temperature and hence the noise

I knew that, but I didn't say it very well, did I?

What I *meant* was that in essentially NO application where a "low
noise" resistor is called for, will there be enough electrical power
dissipation in the resistor to cause it to become warm. In that sense,
any resistor you put there will exhibit the same amount of thermal noise.

Isaac

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

In article <7_mdnb24x5fb_jbdRVn-sQ@comcast.com>,
"Arny Krueger" <arnyk@hotpop.com> wrote:

> TonyP wrote:
> > "Isaac Wingfield" <isw@witzend.com> wrote in message
> > news:isw-301A53.19580318052004@netnews.comcast.net...
> >> The noise is not due to heating, There are two sources of noise in
> >> resistors, thermal noise and "excess noise". Thermal noise is a
> >> function of temperature and resistance, and nothing you (or the
> >> manufacturer) can do will alter it.
> >
> > Saying thermal noise is not due to heating, is a bit of a misnomer.
> > Sure there will always be thermal noise at any temperature above
> > absolute zero, but heating will obviously increse the temperature and
> > hence the noise
>
> Long ago I was building (tubed) RIAA preamps. I had a goodly collection of
> small precision wirewound resistors at my disposal, so I built a stereo
> preamp made up of them. The difference in noise levels, compared to carbon
> compostiion resistors, was negligable.

Wirewound resistors can be rather inductive, and that can make for
"interesting" stability problems.

> Some time later I was building transistorized RIAA preamps, but this time
> the comparison was between carbon film resistors and deposited metal
> resistors. Similar results.

Compared to the groove noise, I don't think anything about the resistor
matters 8^}.

IMHO, the noise level when the stylus is not in the groove is of no
concern as long as it's at least 10 dB below the in-groove value. It
doesn't take *real* low-noise technique to achieve that.

When I designed my own preamp, I selected the topology for lowest
distortion instead of lowest noise -- that meant using a long-tailed
diff pair for the front end. A single bipolar transistor running at
microamp base currents shows considerable distortion due to Rbe
modulation.

Oddball piece of information: The Rbe of a transistor is not an actual
resistance, and does not behave as one, noise-wise. This is a Good
Thing, because at very low collector currents, Rbe can be interestingly
large.

Isaac

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

Isaac Wingfield wrote:
> In article <7_mdnb24x5fb_jbdRVn-sQ@comcast.com>,
> "Arny Krueger" <arnyk@hotpop.com> wrote:
>
>> TonyP wrote:
>>> "Isaac Wingfield" <isw@witzend.com> wrote in message
>>> news:isw-301A53.19580318052004@netnews.comcast.net...
>>>> The noise is not due to heating, There are two sources of noise in
>>>> resistors, thermal noise and "excess noise". Thermal noise is a
>>>> function of temperature and resistance, and nothing you (or the
>>>> manufacturer) can do will alter it.
>>>
>>> Saying thermal noise is not due to heating, is a bit of a misnomer.
>>> Sure there will always be thermal noise at any temperature above
>>> absolute zero, but heating will obviously increse the temperature
>>> and hence the noise
>>
>> Long ago I was building (tubed) RIAA preamps. I had a goodly
>> collection of small precision wirewound resistors at my disposal, so
>> I built a stereo preamp made up of them. The difference in noise
>> levels, compared to carbon compostiion resistors, was negligable.
>
> Wirewound resistors can be rather inductive, and that can make for
> "interesting" stability problems.

I've heard that story, but even though it was a RIAA implemented via
feedback, no problems with oscillation or ringing. Of course, in a RIAA
network, there were big caps across the resistors in the feetback path. And,
the feedback path pretty much controlled how the preamp worked.

>> Some time later I was building transistorized RIAA preamps, but this
>> time the comparison was between carbon film resistors and deposited
>> metal resistors. Similar results.

> Compared to the groove noise, I don't think anything about the
> resistor matters 8^}.

Agreed.

, the noise level when the stylus is not in the groove is of no
> concern as long as it's at least 10 dB below the in-groove value. It
> doesn't take *real* low-noise technique to achieve that.

Agreed.

>I designed my own preamp, I selected the topology for lowest
> distortion instead of lowest noise -- that meant using a long-tailed
> diff pair for the front end. A single bipolar transistor running at
> microamp base currents shows considerable distortion due to Rbe
> modulation.

These transistors didn't have a lot of beta, the collector current was
several mA, so the base currents were probably dozens of microamps.

> Oddball piece of information: The Rbe of a transistor is not an actual
> resistance, and does not behave as one, noise-wise. This is a Good
> Thing, because at very low collector currents, Rbe can be
> interestingly large.

Agreed.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

"Don" <TAKE-OUTdobrien25@comcast.net> wrote in message
news:uyxqc.74473$536.12094292@attbi_s03...
> Is it better to use over rated (higher wattage) resistors for low noise,
or
> just enough wattage capability to cover expected conditions plus a little
> more for safty ?
>
> My thinking is that over rating will result in cooler resistors, so
therefore,
> less noise, but, on the otherhand, more material for the signal to pass
> through, therefore, more noise.
> -Don


Check out Randall Aiken's website for an excellent technical paper on the
subject of resistor types. There's actually 3 types of resistor noise.

http/www.aikenamps.com/

Click on Tech Info, then Technical Papers Advanced, then on "Resistor
Types - Does it Matter?


Mikey

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

"Isaac Wingfield" <isw@witzend.com> wrote in message
news:isw-5E2E1E.20221819052004@netnews.comcast.net...
> Compared to the groove noise, I don't think anything about the resistor
> matters 8^}.

True.

> IMHO, the noise level when the stylus is not in the groove is of no
> concern as long as it's at least 10 dB below the in-groove value. It
> doesn't take *real* low-noise technique to achieve that.

Depends on the noise, but I would want a slightly better margin than that,
and is very easy to achieve anyway.

> When I designed my own preamp, I selected the topology for lowest
> distortion instead of lowest noise -- that meant using a long-tailed
> diff pair for the front end. A single bipolar transistor running at
> microamp base currents shows considerable distortion due to Rbe
> modulation.

Since the distortion on any vinyl record is also high, you are reducing one
non-problem, whilst claiming another is of no importance.

TonyP.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

TonyP wrote:
> "Isaac Wingfield" <isw@witzend.com> wrote in message
> news:isw-5E2E1E.20221819052004@netnews.comcast.net...
>> Compared to the groove noise, I don't think anything about the
>> resistor matters 8^}.
>
> True.
>
>> IMHO, the noise level when the stylus is not in the groove is of no
>> concern as long as it's at least 10 dB below the in-groove value. It
>> doesn't take *real* low-noise technique to achieve that.
>
> Depends on the noise, but I would want a slightly better margin than
> that, and is very easy to achieve anyway.

Agreed. You have to consider not only the over-all amplitude of the noise,
but also its spectum.

>> When I designed my own preamp, I selected the topology for lowest
>> distortion instead of lowest noise -- that meant using a long-tailed
>> diff pair for the front end. A single bipolar transistor running at
>> microamp base currents shows considerable distortion due to Rbe
>> modulation.
>
> Since the distortion on any vinyl record is also high, you are
> reducing one non-problem, whilst claiming another is of no importance.

Same basic comment as noise. The spectral content of the nonlinear
distortion have to be considered. However, it's trivial to build electronics
with nonlinear distortion that is so much less than that of the LP, that
there's not a lot to worry about.

IME, the most common audible issues relating to phono preamps relate to
frequency response, both that due to the RIAA demphasis network, and that
due to cartridge loading.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

"MikeyMann" <mikeyamps@comcast.net> wrote in message
news:TLCdna78AOMz_TDdRVn-uQ@comcast.com...
> "Don" <TAKE-OUTdobrien25@comcast.net> wrote in message
> news:uyxqc.74473$536.12094292@attbi_s03...
> > Is it better to use over rated (higher wattage) resistors for low noise,
> or
> > just enough wattage capability to cover expected conditions plus a
little
> > more for safty ?
> >
> > My thinking is that over rating will result in cooler resistors, so
> therefore,
> > less noise, but, on the otherhand, more material for the signal to pass
> > through, therefore, more noise.
> > -Don
>
>
> Check out Randall Aiken's website for an excellent technical paper on the
> subject of resistor types. There's actually 3 types of resistor noise.
>
> http/www.aikenamps.com/
>
> Click on Tech Info, then Technical Papers Advanced, then on "Resistor
> Types - Does it Matter?
>
>
> Mikey


Great page, Thanks
Dale

 

[Guest]

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"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:vYqdnXPMztw_ZTDd4p2dnA@comcast.com...
> Same basic comment as noise. The spectral content of the nonlinear
> distortion have to be considered. However, it's trivial to build
electronics
> with nonlinear distortion that is so much less than that of the LP, that
> there's not a lot to worry about.

Agreed.

> IME, the most common audible issues relating to phono preamps relate to
> frequency response, both that due to the RIAA demphasis network, and that
> due to cartridge loading.

Cartridge loading is usually easy to fix, and IME freq response errors are
usually much less than the variation in the records themselves.
Whilst it is good practice to set up a flat system using a good test record,
the variation in response from supposedly identical records, but from
different pressings, will usually be larger than any phono pre-amps
variation from ideal RIAA response. Worrying about variations less than 1-2
dB is a waste of time IMO.

TonyP.

 

[Guest]

Archived from groups: rec.audio.tech (More info?)

TonyP wrote:
> "Arny Krueger" <arnyk@hotpop.com> wrote in message
> news:vYqdnXPMztw_ZTDd4p2dnA@comcast.com...
>> Same basic comment as noise. The spectral content of the nonlinear
>> distortion have to be considered. However, it's trivial to build
>> electronics with nonlinear distortion that is so much less than that
>> of the LP, that there's not a lot to worry about.
>
> Agreed.
>
>> IME, the most common audible issues relating to phono preamps relate
>> to frequency response, both that due to the RIAA demphasis network,
>> and that due to cartridge loading.

> Cartridge loading is usually easy to fix,

But IME rarely fixed.


> and IME freq response
> errors are usually much less than the variation in the records
> themselves.

However, that doesn't let them off the hook. If they are audible then they
represented undesirable changes in sound quality.

> Whilst it is good practice to set up a flat system using
> a good test record, the variation in response from supposedly
> identical records, but from different pressings, will usually be
> larger than any phono pre-amps variation from ideal RIAA response.

I'd be careful about *any*, particularly when it comes to legacy preamps
from before the 1980s, that are still in use.

> Worrying about variations less than 1-2 dB is a waste of time IMO.

It very much depends where those 1-2 dB are.

Take a listen to the differences from variation that size that you can hear
in musical samples you can download from
http/www.pcabx.com/technical/dips_pips_tips/index.htm , particularly the
ones I call "tips".

IME mastering is often about broad but shallow changes in frequency
response.

 

[Guest]

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TAKE-OUTdobrien25@comcast.net (Don) wrote in message news:<uyxqc.74473$536.12094292@attbi_s03>...
> Is it better to use over rated (higher wattage) resistors for low noise, or
> just enough wattage capability to cover expected conditions plus a little
> more for safty ?
>
> My thinking is that over rating will result in cooler resistors, so therefore,
> less noise, but, on the otherhand, more material for the signal to pass
> through, therefore, more noise.
> -Don

Purely for fun, I did a test today. My test setup is a x100 amplifier
(with OPA2228 op amp) feeding the sound card on my PC, whereupon I
have a crude FFT spectrum analyzer program. So I took two resistors as
"signal sources" to compare their noise spectra. One was a 100k 1/4 W
metal film, the other was a 100k 1/8 W carbon film. They were close
enough in resistance on an ohmmeter to rule out resistance variation.

The carbon film had 6 percent more voltage noise from essentially zero
up to 20 kHz, give or take 1 percent. This is about 0.5 dB. Does
anybody out there have a real "professional" spectrum analyzer or
digital scope? This should be an easy measurement if you have the
right equipment.

I don't know if I would choose a metal film resistor in an audio
circuit on this basis. If 0.5 dB makes a difference, then it may be a
questionable design, since you can usually arrange matters so the
front end op amp is the dominant noise source.

Where I have seen it make a difference is in something like a
transimpedance front end for optical detection, where the resistor is
often the dominant noise source.

 

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"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:tdWdnUrNUKgBDy3d4p2dnA@comcast.com...
> > Cartridge loading is usually easy to fix,

> But IME rarely fixed.

Yes it's amazing how many people would rather buy a new pre-amp or
cartridge, than a 10 cent capacitor
I buy cartridges based mainly on tracking performance (Shure V15VMR) then
adjust loading to suit.

> > and IME freq response
> > errors are usually much less than the variation in the records
> > themselves.

> However, that doesn't let them off the hook. If they are audible then they
> represented undesirable changes in sound quality.

But how are they audible, only when doing a direct comparison with something
else?
Which then is the more accurate? How do you know? Does it matter if it
sounds good to you?

> > Worrying about variations less than 1-2 dB is a waste of time IMO.
> It very much depends where those 1-2 dB are.

Not at all, since the records frequency variation will be all over the
place. Simply adjust tone controls to taste. That's what the mastering
engineer does anyway!

> Take a listen to the differences from variation that size that you can
hear
> in musical samples you can download from
> http/www.pcabx.com/technical/dips_pips_tips/index.htm , particularly the
> ones I call "tips".

When listening to records I don't usually ABX them to the master tapes. So I
have no idea which pressings are more accurate. Only which sound better to
me at the time.

> IME mastering is often about broad but shallow changes in frequency
> response.

As is the response variation in most pre-amps.
IME the mixing/mastering, total EQ will be *MUCH* greater overall. And not
flat to any reference whatsoever.

TonyP.

 

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Archived from groups: rec.audio.tech (More info?)

TonyP wrote:
> "Arny Krueger" <arnyk@hotpop.com> wrote in message
> news:tdWdnUrNUKgBDy3d4p2dnA@comcast.com...
>>> Cartridge loading is usually easy to fix,
>
>> But IME rarely fixed.
>
> Yes it's amazing how many people would rather buy a new pre-amp or
> cartridge, than a 10 cent capacitor

Exactly.

> I buy cartridges based mainly on tracking performance (Shure V15VMR)
> then adjust loading to suit.

Exactly. Mistracking is a lot harder to fix downstream than FR problems.

>>> and IME freq response
>>> errors are usually much less than the variation in the records
>>> themselves.

>> However, that doesn't let them off the hook. If they are audible
>> then they represented undesirable changes in sound quality.

> But how are they audible, only when doing a direct comparison with
> something else?

It's often apparent without comparison.

> Which then is the more accurate?

The one you get when you get the FR of the playback equipment right.

> How do you know? Does it matter if it sounds good to you?

I find that if you get the FR of the playback equipment right, more
different recordings sound good to me.

>>> Worrying about variations less than 1-2 dB is a waste of time IMO.

> > It very much depends where those 1-2 dB are.

> Not at all, since the records frequency variation will be all over the
place.

Right, but I find that there is a natural centerline out there someplace.

> Simply adjust tone controls to taste. That's what the mastering
> engineer does anyway!

It's nice to be able to play a stack of recordings without constantly
fiddling with the gear.


>> Take a listen to the differences from variation that size that you
>> can
> hear
>> in musical samples you can download from
>> http/www.pcabx.com/technical/dips_pips_tips/index.htm ,
>> particularly the ones I call "tips".

> When listening to records I don't usually ABX them to the master
> tapes. So I have no idea which pressings are more accurate. Only
> which sound better to me at the time.

Yes, but if you can tune the playback system so that it is closer to the
median without adjustments, it takes less individual adjustment to sound
right with a variety of recordings.

>> IME mastering is often about broad but shallow changes in frequency
>> response.

> As is the response variation in most pre-amps.

Exactly.

> IME the mixing/mastering, total EQ will be *MUCH* greater overall.

Not necessarily. While I'm not shy about applying eq, I often make
recordings where many tracks if not the whole mixdown has minimal or zero
eq.

> And not flat to any reference whatsoever.

We all carry a reference around in our heads - it's the composite of
everything we've ever heard.

 

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"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:IP6dnSdQi_yD2C7d4p2dnA@comcast.com...
> > But how are they audible, only when doing a direct comparison with
> > something else?
> It's often apparent without comparison.

Not sure how you would know whether it's the equipment or the record?
If they put test tones on every record you may have a shot.

> > Which then is the more accurate?
> The one you get when you get the FR of the playback equipment right.

Not necessarily. If the record has say 3dB droop at HF compared to the
master tape, then the cartridge/pre-amp with a 3dB rise will be more
accurate for that record.

> > How do you know? Does it matter if it sounds good to you?

> I find that if you get the FR of the playback equipment right, more
> different recordings sound good to me.

I already stated that you should set the response flat using a good test
record. Then you can ignore the 1-2 dB variations from RIAA that your
cartridge/pre-amp might have, safe in the knowledge that the records you
play will be far more than that anyway. Compensate with EQ as necessary.

> > Not at all, since the records frequency variation will be all over the
> place.
> Right, but I find that there is a natural centerline out there someplace.

I don't, but getting as flat as possible with a test record, is a good place
to start anyway.

> > Simply adjust tone controls to taste. That's what the mastering
> > engineer does anyway!
> It's nice to be able to play a stack of recordings without constantly
> fiddling with the gear.

Of course you can, but that doesn't mean they will all sound similar in
tone, or similar to what the mixing or mastering engineers heard. You can't
even expect that from CD's.

> > When listening to records I don't usually ABX them to the master
> > tapes. So I have no idea which pressings are more accurate. Only
> > which sound better to me at the time.

> Yes, but if you can tune the playback system so that it is closer to the
> median without adjustments, it takes less individual adjustment to sound
> right with a variety of recordings.

Of course, but that was never the argument.

> > IME the mixing/mastering, total EQ will be *MUCH* greater overall.
>
> Not necessarily. While I'm not shy about applying eq, I often make
> recordings where many tracks if not the whole mixdown has minimal or zero
> eq.

Sure, but that would be the exception, not the rule.

> > And not flat to any reference whatsoever.
> We all carry a reference around in our heads - it's the composite of
> everything we've ever heard.

Yep, and everybody's is different. To be a reference, you need a common
standard.

TonyP.