Frequently Asked Questions
Reno Hi-Fi and Pass Labs are available to personally help you
with any questions or concerns. Reno Hi-Fi can be contacted at
and by phone at 775-829-7332. Pass Labs help is
and phone 530-367-3690. Reno Hi-Fi and PASS constantly hear
that we are some of the most helpful, dedicated and accessible
professionals in the audio industry. Below are some Frequently
Asked Questions and answers to frequent misconceptions about
Where can I find reviews of Pass Labs products?
There are many reviews of Pass Labs products on the “Reviews &
Awards” page at www.PassLabs.com.
How do I register my Pass Labs or First Watt warranty?
The Pass Labs and First Watt warranties are three-full-years and
are automatically transferred, without notice to the factory, to
the owner of the product during the three-year warranty period.
You don’t need to do anything. Pass Labs’ policy is that the
warranty starts when the product leaves the factory. Reno Hi-Fi
keeps a huge inventory of new Pass Labs products in stock, and
this stock may be in inventory from a few days to a few months.
When a new product leaves Reno Hi-Fi, it has a full three-year
factory warranty. Upon request, after the ten-day in-home demo,
and after the product is fully-paid and any trade-in item is
received in the condition stated by the buyer, Reno Hi-Fi will
mail a signed receipt on Reno Hi-Fi letterhead stating the
warranty (which of course will be the length promised when the
transaction was started). Reno Hi-Fi has never had a warranty
Is a product the latest version from Pass Labs?
There is only one version of PASS XA.5 amps. There has been no
change, and there are no changes planned to the XA.5 line
(XA.30.5, XA-60.5, XA-100.5, XA-160.5 and XA-200.5). All the
XA.5 amps of any particular model are the same.
There are two versions of the X.5 amps (X-150.5, X-250.5,
X-350.5, X-600.5, X-1000.5). Amps manufactured before February
2008 are very slightly different than those made after that
date. There is an obvious way to tell which version of the amp
when you look at it, while sonically the changes are very
subtle. The newer and revised X.5 amps have a “signal ground
pin” on the rear of the amp, and the earlier models do not have
a signal ground pin. Also, the newer version of the X.5 amps
received a layout change that some listeners feel offers a
slight performance advantage. Any listening improvements as a
result of these changes is small and frequently system
dependant. Either version of this product represents an
excellent sonic investment.
What is a “Signal Ground Pin?”
This pin is a connector allowing an “audio signal ground
reference” connection for a powered subwoofer. When a powered
subwoofer is connected to the speaker-level connection (rather
than connected to the line-level connection from the preamp
output) the subwoofer amplifier negative connection should be
made to a negative (-) zero-voltage ground reference. This
connection should not be made to an amplified negative output.
All Pass Labs X amps (all X, X.5, XA and XA.5) have amplified
negative speaker outputs because the amps are internally a
bridged design. The signal ground pin makes connecting a
subwoofer extra easy and safe. Connecting a powered subwoofer to
the amplifier negative output terminal will damage some
subwoofers and may damage the power amplifier.
How do I connect a powered subwoofer to an amp without a signal
First, consider using the line-level connection from the preamp
output as this eliminates all issues of negative speaker
terminal connections and potential conflicts. In the case where
you most want to use the speaker level connection, the powered
sub must be connected to a negative zero-voltage ground. Make
the negative connection to the negative terminal of the power
amp input not in use. If you are connecting your preamp to the
power amp using the XLR input to the amp, then use the negative
(shell) connection on the RCA connector to supply your sub with
a negative ground. And if you are connecting your preamp to the
power amp via the RCA connector, then use Pin #1 in the XLR
connector for a signal ground reference for the sub. All
full-range speaker systems of which we are aware today that have
a built in amp for the sub woofer (like Martin Logan speakers)
do not have a conflict using the amplified negative to power
their amps. Many powered subwoofers also do not have a
problem being driven with an amplified negative signal; check
your sub’s owner’s manual.
From the Pass Labs Owner’s Manual regarding subwoofer
“Some powered subwoofers
require an audio signal ground reference, and their makers may
suggest that a black speaker terminal is where this voltage
reference might be found. On complementary designs, which would
be typical of all power amps produced by Pass Laboratories™,
this is an incorrect and unsafe assumption. On all Pass
Laboratories™ power amplifiers a reference of 0 volts will be
found only at pin 1 of the XLR input or at the shell of the RCA
connections for these devices require special consideration when
used with our product. If you have such a device, and wish to
use it with our product, please contact our Foresthill,
California factory for specific instructions.... you have been
Should I change the capacitors in my used amp?
Almost always, the answer to this question
is an emphatic NO! If your amp is not humming through a speaker,
and usually just one speaker, then there is probably no reason
to go to the unnecessary expense, shipping, and damage risks to
have capacitors replaced. Modern, high-quality capacitors, in an
amp that is not abused will last thirty-years and beyond—no
kidding. Mark Sammut, owner of Reno Hi-Fi, has a Threshold 400A
built in 1977 that has been in daily use in his TV room for
nearly 35 years, and the amp works perfectly. Though the power
switch has needed replacement twice and a few LED lights are
burned-out, the capacitors are fine. Nelson Pass has written in
Pass Labs owner’s manuals: “More
to the point, we would suggest that you not worry about
[capacitor failure]. This is a conservatively built industrial
design, not a tweaky tube circuit run on the brink of failure.
If it breaks, we will simply get it fixed, so sleep well.”
When do capacitors need to be replaced?
Caps give years of warning before they need to be replaced. If
the amp is humming though a speaker, then it might be time for
replacement. If an amp has been placed in a closed cabinet and
overheated, then this abuse can cause cap failure. If an amp has
been modified by a consumer, and subsequently damaged, caps may
Pass Labs Refurbished product offered by Reno Hi-Fi always has
capacitors and all other electronic components checked for
soundness, and any electronic component that is remotely
marginal is replaced. PASS refurbishing also insures that the
product has not been tampered with or modified by a consumer.