Let’s talk about a major problem with records: Namely, extraneous
noises—clicks, pops, crackles, sizzles, etc. Even those of us who
continue to support records would love to get rid of these annoying
background noises. As we all know, the amount of the background
noise can be reduced by cleaning our records with a good record
cleaner, such as those produced by VPI and Nitty Gritty. Using a
good turntable, arm, and cartridge can further reduce annoying noises.
However, that only gets us so far.
- In the 1970s, a few companies such as SAE, Burwin and Garrard
marketed black boxes which claimed to eliminate impulse noises—clicks,
pops, ticks. To a limited degree, they were successful in at least
reducing such noises—especially the ones caused by large scratches.
By the mid 1980s, however, these devices were no longer being manufactured.
Today the used price for these units vary between about $150 and
$400. There are still a few companies manufacturing devices which
address record noise, but for the most part they are quite expensive
(e.g., the Packburn costs $2,650, and the Cedar $19,000).
- I recently became aware of a relatively new product called Surface
Noise Reducer (SNR) being sold by Esoteric Sound for $450. Quoting
from Esoteric Sound’s literature, “The Surface Noise Reducer circuit
topology employs the latest in modern digital integrated circuits
and a design algorithm which can identify and remove most clicks
and pops found on records and even 78’s and other vintage records...
The Esoteric Surface Noise Reducer acts only on the click or pop
without effecting program material.”
- The SNR circuitry is contained in a 12+ by 7 by 1+ inches box,
with an attached 19 inch faceplate which makes the unit suitable
for rack mounting. The unit can be connected through a tape or processor
loop, or between the phono preamp and the preamp. On the front of
the unit are two dials, and a toggle switch. The switch is used
to toggle between processing and bypass. In bypass mode, the signal
path is hard-wired input to output, therefore it shouldn’t introduce
any noise or distortion. The right hand knob allows you to set the
amount of noise reduction, while the left-hand knob is used to limit
distortion by curtailing the noise reduction at appropriate times.
According to company literature, hum and noise is 95 dB below rated
output, THD is less than 0.02 percent at 1 kHz, and response is
20 to 20 kHz +/- 0.20 dB. The SNR is easy to use, as can be seen
from the following instructions:
- While playing loud passages, advance the Distortion Limiting
control until the THD LED illuminates. Now back off the Distortion
Limiting control slightly.
- Advance the Quieting control until the NR LED flashes indicate
that clicks and pops are removed.
- Carefully adjust the Quieting control for maximum reduction
of noise without introduction of distortion.
- If you notice distortion during loud peaks, advance the Distortion
Limiting control further until the THD LED illuminates and thus
inhibits the NR LED and resultant distortion. This may require
careful adjustment of both controls; some interaction will be
observed.
- How well did the unit work? During the past few weeks, I listened
to dozens of records, in various conditions, using the SNR (for
this review, records were played on a VPI HW-19 Mk III, with a Rega
RB300 arm and a Blue Point cartridge). The SNR works similarly to
the SAE, Burwin and Garrard units in that it identifies the impulse
noise, and cuts the signal for a fraction of a second to remove
the noise, and then backfills the missing signal to match the surrounding
signal. Like the other units, when the SNR removes an impulse noise,
it leaves a sonic footprint, in place of the click or tick, in the
background behind the music. I’d describe the sonic footprint as
being a dull or soft pop at a lower volume than the impulse noise.
For the most part, the music masks this slight noise; however, when
the music is soft, or during the gap between cuts, the noise can
be heard. I found the sonic footprint generally much less annoying
than the click or pop which it replaced. The unit had little if
any effect on other types of surface noise such as sizzle and crackle—but
then it wasn’t designed to remove such noise.
- For some records, the results were outstanding, while for others
only a slight improvement—it depended on the type of background
noise on each record. If the problem was clicks, pops and ticks,
the unit did a great job; On the other hand, if the problem was
sizzle and/or crackle, there was only a slight improvement.On average
I’d say there was a full grade improvement on most records. For
example, good records became very good records, very good records
became excellent.
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Mike Stosich of Esoteric Sound informed
me that when there are fluctuations in voltage, this could increase
the residual noise (soft dull pop) left after the tick/pop has been
eliminated. To correct this problem, Esoteric began adding a voltage
regulator to the SNR units. After he had added a voltage regulator to
my unit, I did extensive listening. While it’s tough to compare my memory
of the units performance before the voltage regulator to its performance
after, I believe there was a slight improvement—but it’s a difficult
call.
- After a while, I became aware that more wasn’t necessarily better
than less. Sometimes moderation in noise reduction is the best policy.
This became clear while listening to George Winston’s Piano Solos.
This album had a great many very fine scratches, few moderate scratches,
a no major scratches. When the quieting knob was turned high enough
to identify and process the very fine scratches, the resulting dull
pops were more intrusive than the ticks had been. These dull pops
could be heard between each note, and were very distracting. By
reducing the amount of noise reduction, the dull pops went away,
and the volume of the tiny ticks was so low they generally couldn’t
be heard.
For the first couple of days I was constantly tweaking the knobs.
After that, I found that I was generally setting the distortion
limiting knob at about 11 o’clock, and the quieting knob at
about 1 o’clock. I finally decided to leave them there, and
feel I’m getting most of the benefit of the unit without any
audible distortion. Now I only tweak the setting when I get an unusual
album such as the George Winston album discussed above. I also will
probably do some tweaking when I tape a record.
- Did the SNR affect the quality of the sound? Did it add or eliminate
something? When the SNR was in the bypass mode, there was absolutely
no change to the music. This was an easy A/B test. The unit was
in the tape loop, so by leaving the SNR in the bypass mode I was
able to switch the SNR in and out by using the pre-amp tape button.
Whether the SNR, when in the active mode, added or subtracted something
from the music is a harder call. I spent a lot of time switching
between bypass and active, and didn’t hear any difference in the
music, but with the background constantly changing (ticks/pops being
eliminated/reduced), I can’t be absolutely sure that the music remained
exactly the same. I can’t say for certain that there were no changes.
If there were, they were very small.
- With devices such as the SNR, it’s important to have realistic
expectations. You can’t expect all extraneous noise to be eliminated,
but you can expect some improvement. Shortly after I purchased the
SNR, Mike Stosich sent me an early version of a cassette tape (C-60,
high bias, Dolby B) made on their digital audio workstation which
is used to demonstrate what the SNR is capable of accomplishing.
The cassette compares the SNR to the Packburn and Cedar noise reducing
units four 78 selections, 2 LP selections (the current version has
four LP selections), a 1 kHz signal plus scratches selection, and
a selection containing calibration scratches. When listening to
each tape selection, you first hear the selection with no noise
reduction, then the selection as processed through the SNR, then
through the Packburn, and finally through the Cedar. Interestingly,
the SNR did a better job than the Packburn on the record and scratch
selections, and better than the Cedar on the scratch selections.
But the Cedar did a much better job than either the SNR or Packburn
in cleaning up LP noises. It didn’t just stop at eliminating or
reducing impulse noise; it also did a credible job on sizzle, crackle
and other grungy noises (you get a lot for $19,000).
- For those of you who still enjoy listening to records, you should
consider adding the SNR to your system. I’m very pleased with mine.
If you’re interested in purchasing an SNR ($450, plus shipping charge;
postage to Northern California cost me $6.50, so I imagine it would
be the same to Southern California), receiving the demonstration
tape ($5.00), or a free catalog, Esoteric Sound can be reached at
4813 Wallbank Ave., Downers Grove, IL 60515 (phone/fax: 708-960-9137).
If you call, you’ll first get the fax connection and then in a moment,
you’ll get their answering machine.
- Larry Calhoun
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