Proceed AMP 3 Outstanding 3 channel amp in excellent condition

Proceed AMP 3 in excellent condition. Functions perfectly. I picked 8/10 because I am the second owner and it has 1 tiny scratch on top shown in pics that I just noticed. I bought it from a friend. Used in a smoke free, pet free environment for home theater. Included are three Belden balanced cables.

"...the Proceed AMP 3 is certified for use in Home THX audio systems.
Madrigal engineers have created powerful, versatile and extraordinarily
musical power amplifiers, using the technology and design methodology
for which they have become so well known. Equally suited to the rigors
of film soundtracks and the finesse of high end music reproduction, the
Proceed amplifier serves both needs quite well. In today’s growing
market for multi-purpose systems, they represent an extraordinary
value." - taken from the Proceed AMP 3 Owner's Manual.

Proceed was a division of one of the best companies in audio, Madrigal
Laboratories, which also produced Mark Levinson products costing up to
$60,000. Proceed specialized in home theater components; however, their
amplifiers were so highly regarded that they were often used in high
end, two channel audio systems.

Proceed components were considered to be one of the most cost effective
lines of high end equipment ever produced, as one would have to spend
about 40% to 50% more to find a (slightly) better performing component.
Their amplifiers share similar design features, circuitry and components
with the Mark Levinson products that often cost over $10,000, so they
can easily drive any speaker and make them sound their best.

Each channel contains a dedicated, low impedance power supply, so this
3-channel amplifier behaves as if it were three completely independent,
high end mono amplifiers contained in one chassis. In addition, this
amp features dual-differential design to allow for true balanced
operation, and accepts both RCA (single-ended) and XLR (Balanced)
inputs. These features are very rare in a multi-channel amplifier, as
most share a single power supply across all channels, and are not fully
balanced.

This amplifier still works flawlessly and a PDF copy of the Owner’s
Manual will be included with purchase. It will be safely and
securely boxed.

SPECIFICATIONS
Rated power output: 150 w/ch rms @ 8W, all channels driven,
20 Hz–20 kHz with no more than 0.1%
THD
250 w/ch into 4W
Frequency response: within 0.1 dB from 20 Hz to 20 kHz
Signal to Noise ratio: main outputs - better than –80 dB (ref. 1 w)
Input impedance: 30 kohms (balanced)
100 kohms (single-ended)
Voltage gain: 23 dB (balanced)
29 dB (single-ended)
Input sensitivity: 2.4 V for full rated output (balanced)
1.2 V for full rated output
(single-ended)
Power consumption: typically 210 W at idle (AMP 3)
Output impedance: less than 0.05W.


More details from the manual:

Consistent with the finest amplifiers, your Proceed AMP is a true “multiple mon-
aural” design. Each audio channel has its own, dedicated power supply—includ-
ing a separate 300VA toroidal transformer for each channel. This approach re-
duces crosstalk between audio channels for superior imaging and reproduction
of acoustic space. The demands placed on one channel have virtually no effect
on the performance of the other channel(s).

A critical factor in the ultimate performance of an amplifier is its “power supply
impedance,” which can be loosely thought of as the freedom with which the au-
dio circuitry has access to the power it needs, when it needs it. The design of
your Proceed AMP has addressed this important characteristic in a comprehen-
sive fashion. For example, the power supply capacitors (which act as “reservoirs”
of power for the amplifier circuitry) are mounted directly to the printed circuit
board, immediately adjacent to the output transistors (which require the greatest
amount of current). The layout of the circuitry uses short, thick traces for high
current paths. Internal current capability is further enhanced with high purity
copper buss bars. This attention to detail yields an optimal environment in which
the amplifier may operate to its maximum potential.

Each channel of your AMP is individually configurable to receive either balanced
or single-ended inputs. This approach allows you to take full advantage of the
greater immunity from noise, RFI, and EMI which balanced transmission of audio
signals offers on any preamp-to-amplifier connection where it is supported. At
the same time, any or all channels of the amplifier may be configured for single-
ended inputs to maintain compatibility with the majority of preamplifiers avail-
able today. The gain structure of the AMP adjusts automatically when you select
different inputs to facilitate this “mix and match” approach.

Each channel of your Proceed AMP uses eight 150 watt power transistors. These
transistors are all individually tested and sorted, and are used in matched sets to
ensure that no one transistor bears a disproportionate part of the overall load.
The combination of an “overbuilt” design specification and extraordinary attention
to detail in manufacturing improves performance, reliability, and longevity.

Your Proceed amplifier will shut itself down if it senses either the presence of
DC (direct current) at the output or an unsafe operating temperature. In either
case, a power relay will cause the amplifier to be disconnected from the AC
mains. In addition, the AC input to each transformer is fused to protect against
excessive current conditions such as driving shorted outputs. Finally, inrush limit-
ing prevents premature aging of power supply components during power-up, and
switches off-line once the power supply has been charged.

10

Balanced inputs

Robust output stage

Extensive protection

Special Design Features

Home THX Audio
System certification

Lucasfilm, Ltd.® has established minimum standards for the performance of vari-
ous components which may be used in their Home THX® Audio System. With
respect to power amplifiers, the standards address such things as:

• 
  

  a low electrical noise floor to allow low-level information to be
  fully appreciated;
  

  
  


• 
  

  the absence of any mechanical noise (fans noise, transformer wind-
  ing buzzes), for the same reason;
  

  
  


• 
  

  adequate power to meet the demands of modern films (which can
  be quite dynamic);
  

  
  


• 
  

  flat frequency response for accurate reproduction of timbre;
  

  
  


• 
  

  stability into relatively extreme loudspeaker loads, to ensure that
  

  
  

  the amplifier will perform well with a wide range of loudspeakers.
  

  
  

  As you can see from this list, there is nothing about the Home THX amplifier
  specification that is particularly radical. It simply ensures a certain minimum
  standard of performance. In particular, there is nothing in the nature of the
  amplifier specification which prevents anyone from going above and beyond
  the minimum performance levels required by THX certification.
  

  
  

  Both the Proceed AMP 2 and AMP 3 are certified for use in Home THX audio
  systems. In these products, Madrigal engineers have created powerful, versatile
  and extraordinarily musical power amplifiers, using the technology and design
  methodology for which they have become so well known. Equally suited to the
  rigors of film soundtracks and the finesse of high end music reproduction, the
  Proceed amplifier serves both needs quite well. In today’s growing market for
  multi-purpose systems, they represent an extraordinary value.