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ABOUT OUR SOUND

At Decibel, music is in our blood. It’s our passion and our pleasure. The reproduction of music is
a critical component of our identity.


Stylistically speaking High-End audio takes many different forms (panels, full range drivers,
horns, etc). Each form represents a unique discipline, the pursuits of which provide the listener
with a unique auditory lens by which they can experience music.


The audio system at Decibel represents one of our favorite disciplines, the large format horn. A
system like this can have limitless dynamics, energy, and the ability to place instruments right in
the room with you.


The elements for the dB system were pulled from the Eurotubes and Pletka collections. They
represent rare components that came from the golden age of American cinema. Namely RCA,
Altec, and JBL. These components are not often seen outside of books, magazines, and vintage
audio collections (which are usually sealed behind locked doors).


With this in mind Decibel is an unusual space where the large-format-horn system, pursued in
its extreme form, can be consumed by the public. The space at Decibel is NOT pretentious,
ego-driven, or exclusionary. It is a space meant to be celebratory, boisterous, and endlessly
enjoyable. We find that our patrons often stop in for a quick drink and end up staying with us all
evening.


Come to relax, come to party, come to listen, we promise the music won’t stop… except to flip
the record. Our house is your house. Thanks for joining us.


Eddie, Sarah, Matt, Isabeau, Bob & Carla.

ABOUT OUR GEAR

Speakers

-RCA MI-9462 Bass Horns
-Altec 1505 Multicell Mid-Range Horn
-JBL 077 Tweeter
-First Order Passive Crossover (custom in-house design)


This is a three-way horn system centered around a pair of Altec 1505 Multicell horns. These
horns are from the late 40’s, they’re tar filled, and weigh about 100lbs each sans compression
drivers. Each 1505 is mated to a pair of late 50’s era JBL 375’s (alnico magnet). This is an
unusual pairing which required the design and fabrication of a custom dual throat adapter. This
was done in-house using 3D SLA technology. This combination of horn and driver allows for an
extremely wide bandwidth, covering more than five octaves.


Supporting the lowest octaves are the RCA MI-9462 bass horns. This pair is from the early 50’s
and was recovered from a theater in Detroit. They’re in 100% original condition and loaded with
early 50’s University C15W woofers. These unusual woofers feature extra deep straight sided
one-piece paper cones, dual voice coils, and alnico magnets. This combination provides an
unusually high sensitivity while still retaining bass extension into the low 30Hz region.


The last/upper octave is covered by a pair of vintage JBL 077 tweeters. These tweeters utilize
an alnico magnet structure with a ring radiating diaphragm. Crossover point is 10KHz.


These elements are sewn together with an unusual crossover approach. 1 st order electric
circuits are used in conjunction with each channels natural acoustic frequency response to form
the crossover points and slopes. In this sense the crossover does not control each driver
through brute force, rather the crossover works in harmony with each component. This provides
a very different listening experience than the classic Altec and JBL networks.


System sensitivity is 99db 1W/1M and total speaker system weight is apprx 450lbs per
channel…


Amplification
The “House Amplifier” is the JJ Electronic 323. This is a parallel single-ended-triode dual
monoblock design. The output stage run’s a pair of JJ 2A3-40’s in a high voltage condition
producing 20W per channel at >2%THD. This amplifier is a true dual monoblock topology where
only the power/mains cable is shared between channels.


The preamplification is provided by the matching JJ 243 preamplifier. This is a two stage DC
coupled preamplifier that allows us to run a variety of source components and includes a unique
phono stage. The internal phono stage uses four E88C’s and the primary voltage gain stage is a
hybrid cascode design with DC coupled buffer, providing apprx 55db of gain.


Sources
- VPI Scout with JMW9 tonearm and a variety of cartridges (typically Dynavector).
- Modified Marantz CD-4000 with discreet opamps and tube (E88CC) output stage.
- Streaming as needed…


Listening
While the system at Decibel can be experienced anytime during normal business hours, you will
only get a limited, albeit pleasant sense of what the system is capable of. For the die-hard
enthusiasts we invite you to schedule a private listening session. In most cases short sessions
may be booked at no cost for small parties during the hours of 10AM – 3PM, Tues – Fri. We
love audio, and we love to share what we’re passionate about. Don’t hesitate to reach out.
Eddie@Decibel-PDX.com

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