Purveyors of Electronic, Musical and Vintage goods from then, now and in between. 
Since 1982.

FULLY SERVICED / WARRANTED
STEREO EQUALIZERS, REVERBS / SIGNAL PROCESSORS VINTAGE AND USED 

 

Used & Vintage Stereo Signal Processors. EQ's, Spring Reverbs, Dynamic Processors, Delays, Quadraphonic Decoders, DBX units, Tape-Monitor / Signal-Input-Source Selectors, Digital Timers / Rack-mount clocks, Etc. Fully Tested by Qualified personnel with over 58 years combined experience! Ready to GO! Refurbished, Rebuilt where necessary and Warranted. Brands such as ADC, Audio-Source, Bose, dbx, Empire, Marantz, Pioneer RG / SG / SR, SAE Impulse Noise Reduction System, Sansui RA / SE / SR, Sony, TEAC, Yamaha, and many others...
 

AUDIO EQUALIZERS
and our philosophy on them.

"Are Equalizers really necessary? I just paid $THIRTY GRAND$ for my speakers. They shouldn't need any EQ. Right!??"

Short answer is quite probably, maybe-yes, as an EQ will generally be beneficial to many, if not 'most', audio systems.
     Most speaker designers strive to make a speaker's curve as "flat"* as their projected size parameters and target retail price will allow. The human hearing curve is not "flat". Most folks' hearing is accentuated in the midrange (it's where the human voice is centered) and attenuated in the bass and treble. Sort of a reverse "rock-n-roll smile" curve. When you hear a good, "flat" response speaker, it will likely appear to have an over abundance of mids, at least for most listeners. It will also likely have a deficiency in bass and possibly treble. It will most likely sound  "thin", the degree of which can vary from slight to extreme, depending again, on many variables. This might not even be readily apparent when auditioning speakers, but generally if you hear a pair speakers with an appropriately adjusted, EQ engaged, then you listen to it bypassed, you will want to re-engage it as quickly as possible. 

 

 
     The classic arguments against using an EQ have been that an EQ, or any additional inserted signal processing device, makes the signal path less "pure" and adds noise. Also, again, "these speakers were expensive and shouldn't need an EQ". To address the first point, this issue can usually be reduced to a more than desirable point by utilizing a high quality EQ or signal processor. The noise floor should certainly be below audible levels, and it doesn't take too much of an EQ to achieve that for most folks systems.  While the first point is valid, a good EQ's benefits usually far outweigh any minor noise issues, which are probably below most listeners audible limits in the first place. The second issue was answered previously, in the above paragraph.   In fact, the better the speakers, the more they would likely benefit from a reduction of the midrange frequencies, due to their as "flat as possible" curve. Again, this would apply to the average persons hearing curve. Some "cheap" speakers, will have a "rock-n-roll smile" EQ curve built-in by utilizing drivers, crossover and cabinet combinations, that have an over abundance of bass and treble, and a deficit of mids by design. That would beg the question of "why wouldn't they all just do that then". The answer to that is that any respectable speaker manufacturer wouldn't try and dictate a built-in curve into a speaker other than as flat as assigned parameters will allow, for a number of reasons.
     Another less apparent, but still valid reason for utilizing an EQ can be to compensate for listening room acoustic characteristics. This is generally more difficult to assess, but overtime could become a desired need. This need would obviously change with any parameter change in the listening environment. Also, and no offense, but as we age and as we are exposed to various, sometimes, injurious sonic environments and events, our sensitivity to frequency ranges will change.
     One way to look at a specific speaker / listening environment combination is to think of it as a blank artists canvas. A really high quality speaker system would be comparable to a high quality canvas, brushes and material. Said another way, a "non-flat" EQ curve / listening environment / speaker combination is akin to starting your painting with a dirty, blotchy canvas. The listening environment to a well lit room with natural lighting, conducive to a creative mood. Until you "shape" the EQ, there is no painting on the blank canvas. Once you shape the EQ to your tastes, in a way that compliments the speaker design / room combination, you have created your work of art.

    While I can appreciate all the arguments for not using an EQ, in the end, I generally use an EQ with it's curve slightly boosted in the bass and treble frequencies and attenuated through the mid frequencies from "Zero" position (the "rock-n-roll smile" curve). It will usually require adjustment following any change in speakers, listening environment parameter adjustments and with the material I am listening too. I also have a 1/3 octave RTA monitor / spectrum analyzer with a pink noise generator and analyzing mic to establish an accurate "flat" point to start from.

Some other reasons / arguments 'for' having more control over the Equalization electronically (having an EQ) is to compensate for any deficiencies in hearing. There can be an almost infinite myriad of reasons for hearing deficiencies (hearing loss or loss of certain frequency ranges).  Some people may be deficient in certain frequencies by 'nature', or due to events / exposure to past 'sonic environments' (ie; having loud occupations / loud tasks or events (ie; driving a loud truck / piloting a loud boat (think engine and wind noise) or loud aircraft, driving a convertible car for extended periods, riding a motorcycle without  a helmet (again, think exhaust and wind noise) running a jack hammer, panel cutter, grinder etc), ear fatigue from being a musician or simply listening to music being played too loudly, damage from loud weapons / fire arms, or any number of experiences). Simply 'getting older' tends to reduce your ability to hear 'higher frequencies'. If you have any degree of tinnitus, you may need and EQ to help compensate for that. I have had multiple technicians over the years that I have worked with, or have worked for me, that have certain degrees of hearing loss (think about it. There aren't many 'new' electronic techs being trained for the past few decades, so most of them are going to be north of the 'mid century' mark, meaning that they are most assuredly going to have some hearing loss). I has been and is often, that I will hear sonic issues and anomalies that they won't hear, until I accentuate (run the signal through an EQ).

 * Contrary to a somewhat common misconception, "Flat" does not mean "dull". "Flat" refers to the graphic "curve" of a speakers output when analyzed by a spectrum analyzer. Ideally a speaker should be able to reproduce the human hearing range with all frequencies as close to "zero" (even amplitude or "flat") as is practical for the intended design / price point levels. The listener can then modify it from there by various methods (usually some sort of signal processor such as an EQ) to their tastes.
Also, "Flat" on an EQ, does not mean that all the faders / pots are set to 'Zero' (in the middle). That simply means that they are 'Zeroed'. True "Flat" for a room / speaker combination could end up with the faders 'all over the map' and can typically only be achieved with a Spectrum Analyzer / RTA and a Pink noise source / generator.

OUR SERVICED / BENCH TESTED EQ'S, REVERBS, DYNAMIC EXPANDERS, TIMERS ETC:
 

         

NEW LISTING 3/2/2023
(Click on above thumbnails to enlarge photos)
  warranty
RESTORED / REFURBISHED / FULLY SERVICED
PIONEER SG-9800 STEREO EQUALIZER
DUAL 12 BAND STEREO GRAPHIC EQ / EQUALIZER
YES, THE ONE WITH RED LEDS IN EACH FADER CAP
#...636K
Circa 1979-81
SOLD 11/13/2023
SHIPPED TO JAIME IN CALIFORNIA

Original observed condition; Most push switches not latching. No LED's on right side. RCA jacks seem loose. 2 Broken, linear faders.

ü Our technician has completely gone through and 'Certified' this unit. Everything was completely tested and benched.

ü Unit was disassembled for restoration / reconditioning.

ü RCA I/O jacks replaced.

ü Entire Right channel fader assembly replaced (LED's weren't lighting)

ü Tape monitor switch replaced with new as lock had failed (as they normally have by now) so we replaced both with fresh, new switches (should also be good for another 35-40 years)

ü Both Attenuator switch locks had failed (as they normally have by now) so we replaced both with fresh, new switches (should also be good for another 35-40 years)

ü Electrolytic cap in power supply replaced

ü Balance of linear faders cleaned with contact cleaner

ü We checked and replaced lamps where needed.

ü We then tested both channels with a test tone and O-scope, analyzing both channels with and without each independent effect. It was then cleaned inside and out.
ü All 'latched' switches locking fine.

ü All inputs tested and both side produces clean and even sine waves!

ü All functions tested for perfect operation.
Checked with oscilloscope.

ü No audible power supply hum of any kind. Floor noise measured > -60dB! It's dead silent!

Cosmetically, there's a few light striations and a few 'flea bites' along the edge of the face plate  but nothing too distracting. Switch / Fader caps all 'shiny' with really none of the 'green corrosion / patina' we commonly see on about 60% of Pioneer units (just FYI). The AC convenience outlet on the rear panel has some chipping to the bakelite. Also, the right side, sheet metal has some wear to the finish (see photos above). Unit works and sounds great!

Sought after flagship EQ of the Pioneer "Golden Era". This is the EQ designed with the "Pioneer SPEC 1 & 2" system. Great looking Silver-Face Pioneer 24 band Equalizer (12 bands per stereo channel).
 
Pioneer SG-9800 Features include;

- 12 Bands per channel ('One-Octave EQ')
- 70mm 'Long Throw' faders with +-10dB.
- Separate Left and Right EQ Frequency centers are at 16Hz, 32Hz, 64Hz, 125Hz, 250Hz, 500Hz, 1kHz, 2kHz, 4kHz, 8Khz, 16kHz & 32kHz.
- LED lit faders
- EQ Recording function to imprint tapes / CD's / DAT's / Hard Drive with EQ curve for playback on a car stereo or to allow for deficiencies in speakers
- Tape monitor  (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
- -3 & -6 dB input attenuator (useful for DJ, Studio, Live Sound or any application when used with stronger than normal line-level signals)
- Overload indicator for attenuator
- One un-switched AC convenience jack located on the back rated at 100 Watts

Pioneer SG-9800 Original Specs:

# Channels; 2 (stereo)
# Graphic Bands; 12 / Ch.
# Cut / Boost dB's: 10±
Input Impedance: 50kΩ
Output Impedance: 600 Ω
Max Output Votage: 7.5V (1kHz w/ THD of 0.02% and output impedance 47k Ohms)
Signal to Noise Ratio (IHF, A Network, short circuited, 1V Output): 92dB
THD @ 20Hz - 20kHz, All Control Flat Output 1V: 0.006%
THD @ 10Hz - 30kHz, All Control Flat Output 1V: 0.02%
THD @ 1 kHz, All Control Max. Output 3V: 0.01%
THD @ 1 kHz, All Control Flat Output 2V: 0.005%
THD @ 1 kHz, All Control Min. Output 1V: 0.02%
Frequency Response: 5Hz - 100kHz  +0,-3dB

Again, our tech has completely gone through this unit and 'certified' it READY TO GO! Again, cosmetically, there's a few light striations and a few 'flea bites' along the edge of the face plate (see photos above) but nothing too distracting and the Switch / Fader caps are all 'shiny'. This is probably the most sought after of 'vintage, graphic EQ's' out there. We've had about 5 over the past 25 years and they don't hang around long.
Perfect compliment to most any "classic / vintage" audio system (except suckie, modern A/V / surround / 5.1 / 7.1 / BR549 / Home theater systems).
 Measures 16 5/8" wide x 14" deep x 6" high and weighs 15 lbs unpacked.
Includes a pdf, 'e' copy, download of the Pioneer SG-9800 Owners / Users / Instruction manual and the Pioneer SG-9800 Service Manual if purchaser so desires. Includes our standard 30 day limited warranty.
PIONEER SG-9800 STEREO EQUALIZER
Cond. 8+
(C) R.R.
SOLD 11/13/2023
SHIPPED TO JAIME IN CALIFORNIA

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

         

NEW LISTING 3/1/2023
(Click on above thumbnails to enlarge photos)
  warranty
RESTORED / REFURBISHED / FULLY SERVICED
VINTAGE MARANTZ EQ-20 STEREO EQUALIZER
"GOLD SERIES"
DUAL 10 BAND STEREO GRAPHIC EQ / EQUALIZER
Circa 1981-83
M.I.J.
SOLD 11/18/2024
SHIPPING TO KEITH IN COLORADO

ü Our technician has completely gone through and 'Certified' this unit. Everything was completely tested and benched.

ü Unit was cleaned inside and out.

ü Most I/O jack and fader solder joints re-flowed for trouble-free service. 

ü All latched switches still locking properly

ü Balance of linear faders cleaned with contact cleaner

ü Power / Pilot LED working properly

ü We then tested both channels with a test tone and O-scope, analyzing both channels with and without each independent effect. It was then cleaned inside and out.
ü All 'latched' switches locking fine.

ü All inputs tested and both side produces clean and even sine waves!

ü All functions tested for perfect operation.
Checked with oscilloscope.

ü No audible power supply hum of any kind. Floor noise measured 00.3mVAC! It's dead silent!
____________________________

From Marantz's "Golden Era". Marantz gave their entire lineup a facelift in the early 1980's with their 'Gold Series'. I was a dealer for them then, and sold this unit when new.
 
Marantz EQ-20 Features include;

- 10 Bands per channel ('One-Octave EQ')
- 45mm faders with +-10dB.
- Separate Left and Right EQ Frequency centers are at 30Hz, 60Hz, 120Hz, 240Hz, 500Hz, 1kHz, 2kHz, 4kHz, 8Khz, & 16kHz.
- Tape monitor  (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
- One un-switched AC convenience jack located on the back rated at 350 Watts
- True "WORLD AC POWER"™  50 / 60 cycles there is a 110V, 120V, 220V & 240V selector for use anywhere in the world!

 Marantz EQ-20 Original Specs:

# Channels; 2 (stereo)
# Graphic Bands; 10 Per Channel
# Cut / Boost dB's: 10±
Frequency Response: 10Hz~30kHz +/-1dB
Input Voltage / Impedance: 1100mV / 110kΩ
Rated Output Voltage / Impedance: 1V / 3.5kΩ
Signal to Noise Ratio: 110dB
Inter-channel Crosstalk: 70dB @ 1kHz
THD: 0.005%

Again, our tech has completely gone through this unit and 'certified' it READY TO GO! Cosmetically, all the issues are realegated to the top surfaces of the case and face plate with numerous striations, scuffs and one of the previous owners engraved their id info into the sheet metal, but nothing distracting from the front (see above photos). Perfect compliment to most most, vintage audio systems (except suckie, modern A/V / surround / 5.1 / 7.1 / BR549 / Home theater systems because they don't have proper 'Tape Monitors' nor actual I/O Loops). Comes with an 'e-copy / PDF download of the Marantz EQ-20 owners / users manual.
 Measures 17.5" wide x 8" deep x 3" high and weighs ~7 lbs unpacked.
Includes a pdf, 'e' copy, download of the Marantz EQ-20 Owners / Users / Instruction manual. Includes our standard 30 day limited warranty.
MARANTZ EQ-20 STEREO EQUALIZER
Cond. 8
(C) R.R.

SOLD 11/18/2024
SHIPPING TO KEITH IN COLORADO

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

    

NEW LISTING 3/1/2023
(Click on above thumbnails to enlarge photos)
  warranty
SERVICED / FULLY BENCH TESTED
AudioSource
STEREO 10 BAND GRAPHIC OCTAVE  EQUALIZER
AudioSource EQ-100
 #...3739
Circa 1998
SOLD 2/11/2024
SHIPPING TO STEVE IN WISCONSIN

We have completely gone through this unit, checking all controls for cleanliness and I/O solder joints and re-flowing where necessary. All functions tested for perfect operation. All inputs tested and both side produces clean and even sine waves! No power supply hum of any kind. It's dead silent!  All inputs tested and both side produces clean and even sine waves! Checked with O-Scope. No power supply hum of any kind. It's dead silent!
  ____________________________

Great looking and quality AudioSource 10-band  stereo, graphic EQ. The Audio Source EQ-100 covers the following frequencies: 30Hz, 60Hz, 125Hz, 250Hz, 500Hz, 1kHz, 2kHz, 4kHz, 8kHz and 16k. Each frequency also allows cut / boost of a full 12 dB (most home EQ's are only a maximum of 10 dB + or - ).

AudioSource EQ-100 Features include:

- Stereo 10 graphic bands ±12dB
- Separate Left and Right EQ Frequency centers are at 30Hz, 60Hz, 120Hz, 250Hz, 500Hz, 1kHz, 2kHz, 4kHz, 8Khz, & 16kHz.
- 1 Octave centers
- EQ defeat
- EQ Recording function to imprint tapes / CD's / DAT's / Hard Drive with EQ curve for playback on a car stereo or to allow for deficiencies in speakers.
- Tape Monitor (Tape Monitors can also be used for Tape / Video / CD / DVD / VCR / DAT / iPod /MP3 / XM / SIRUS etc. as well as for CDR)
- 10 Band 9-segment, LED, Spectrum Analyzer style display
- AC convenience outlet on the back panel (un-switched @ 200 watts capacity)

AudioSource EQ-100 Original Specs:

# Channels: 2 (stereo)
# Bands: 10 (Separate L&R)
# Cut / Boost dB's: ±12dB
Max Output (RMS V): 10
Frequency Response: 5-100kHz
S/N A-weighted: 90dB
THD: 0.03% @ rated output, 20-20kHz
Input Impedance: 10kΩ
Rated Output Impedance: 600Ω

This is a good looking and performing EQ. EQ built using super quality, de-tented linear controls  with a compact 30mm throw! Again we have completely gone through cleaning it & checking all functions. All controls and switches cleaned for worry-free service. Unit looks near new and works perfectly now.
Includes a pdf, 'e' copy, download of the AudioSource EQ-100 Owners / Users / Instruction manual. Measures 16.5" wide x 8.75" deep x 2.75" high and weighs 7 lbs unpacked. Includes our standard 30 day limited warranty.
AudioSource EQ-100
Condition 8.5+++
(C) R.R.
SOLD 2/11/2024
SHIPPING TO STEVE IN WISCONSIN

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

 

 

AUDIO REVERBS / DELAYS
 

     

    

NEW LISTING 12/15/2023
(Click on above thumbnails to enlarge photos)
  warranty
RESTORED / REFURBISHED / FULLY SERVICED
VINTAGE PIONEER STEREO REVERB AMPLIFIER / DELAY
          SR-303 / SR303 SR-9 SR9
'REVERBERATION AMP' 
#...903M
MIJ

SOLD 12/21/2023
SHIPPED TO ELVIS IN NORTH CAROLINA

Original Issues upon arrival; Typical issues with latching Tape Monitor and Attenuator switches NOT "latching". Some 3-D display lamps out. Noisy potentiometers. All things that are expected.

Our technician has completely gone through and 'Certified' this unit. Everything was completely tested and benched. Unit was disassembled for restoration / reconditioning. Both rotary potentiometers cleaned internally for quiet operation. Most I/O jack and fader solder joints re-flowed for trouble-free service. Tape monitor and Attenuator switches replaced and not 'latch'. We replaced all the display lamps w/ blue tinted #25-995. We then tested both channels with a test tone and O-scope, analyzing both channels with and without each independent effect. It was then cleaned inside and out. All inputs tested and both side produces clean and even sine waves! All functions tested for perfect operation. Checked with O-Scope. No power supply hum of any kind. It's dead silent!
 Unit is clean both cosmetically and sonically. Looks and sounds great!
 ______________________________

The SR-303 is "The-must-have" signal processor for the most desirable, 'Silver-Face / Blue Meter' Pioneer rack mount gear series. Great looking Silver face electronic Reverb / Delay. Unit features  really 'Cool' "Time-Tunnel", Blue display that pulses with the beat. If you choose, you can display it even if you have the effect bypassed. Reverb / Delay depth and time are completely variable for custom tailoring to your tastes. Either effect can be added to recording so you can transfer the sound effect to your auto.  

Features include:
 - Electronic Reverb / Delay depth and time is completely variable for custom tailoring to your tastes
 - 'Reverb Record' feature allows effect to be added to recording so you can transfer the sound effect to your auto
 - Pulsing Green reverb level display
 - Depth control
 - Time Delay control
 - Tape monitor  (Tape Monitors can be used with Tape / Video / CD / DVD / VCR / DAT / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS® CDR (CD recorders as well as for inserting signal processors, such as EQ's, Reverbs, Spatial Enhancers / Dynamic Processors, Noise Reduction units, Special Effects units, Time Delays, etc) Dubbing can be used with CDR (CD recorders) units)
 - -6dB attenuator on rear panel
 - One un-switched AC convenience jack located on the back rated at 100 Watts
 
Specs:
Input Sensitivity / Impedance: 150mV / 150Ω @ 1kHz (@ 1kHz /  'Depth' set @ '0')
Output Sensitivity / Impedance: 150mV / 150Ω @ 1kHz (@ 1kHz /  'Depth' set @ '0')
Maximum Input Level: 2000mV (2V) (@ 1kHz /  'Depth' set @ '0')
Frequency Response: 5Hz-70kHz ± 1dB (w/ 'Depth' set @ '0')
Reverb Time (effect 1): 0-3 Sec @ 400Hz
Reverb Time (effect 2): 25-100mS @ 400Hz
S/N Ratio: 90dB (@ 1kHz / 1V input & 'Depth' set @ '0')
THD: 0.05% (@ 1kHz / 1V input & 'Depth' set @ '0')

Again, we have completely gone through it cleaning all pots and switches. All functions tested perfectly. Looks and sounds great! Measures 16.5" wide x 4" high x 13" deep and weighs 10 lbs unpacked. Includes our standard 30-day limited warranty!
 PIONEER SR-303 REVERB / DELAY
 Cond. 8.5+
SOLD 12/21/2023
SHIPPED TO ELVIS IN NORTH CAROLINA
 
 Note: These units are really impressive when paired up, using one unit for reverb and one for some slight "slap-back" delay. While both effects are available on each unit, it's only one at a time. With two units you can get the full "LIVE" effect, just like in pro-audio systems!

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

              

NEW LISTING 3/1/2023
(Click on above thumbnails to enlarge photos)
  warranty
RESTORED / REFURBISHED / FULLY SERVICED
VINTAGE SANSUI SPRING REVERB
SANSUI RA-500 RA500
STEREO, ANALOG, SPRING REVERB 
EFFECTS UNIT
"VERY FUN!!!"
  "WORLD AC POWER" ™
Circa 1977-82
M.I.J.
for sale
We have completely gone through it cleaning and testing everything. Pilot / Power lamp running 'cool' so should last a very long time. Balance of all display lamps replaced (even though they were all working) with new units (6.3V/ 0.25A / #25-080) for trouble free service. All send and receive coils in the reverb tank in perfect working order and solidly mounted. Springs in good condition w/ no 'stretched' sections. All internal controls, switches and pots cleaned and are quiet. I/O jack solder joints inspected. Works and sounds great.
_____________________________________

Sansui RA-500 Features:
- REAL, 'Analog Spring' Reverb with DUAL tank pickups (instead of the old, 'single' type)
- Infinitely variable Reverb 'Depth' control which also changes the display relative to the amount of the reverb effect you have dialed in
- Dual Tape Monitors (Actual Loops)
- Bi-Directional Tape Dubbing / Copy / Signal Routing
- Reverb 'Record' function allows reverb to go to any recording device connected and enabled
- Reverb Defeat (if you simply want the original, dry signal)
- Reverb Bypass
- Physical Ground Lug on rear panel
- Dual, Un-switched convenience AC outlets on rear panel
- True "WORLD AC POWER"™  50 / 60 cycles there is a 110V, 120V, 220V & 240V selector for use anywhere in the world!

Sansui RA-500 Original Specs:
Rated Output Voltage: 300mV @ 1kHz w/ Reverberation time minimum input level 200mV
Maximum Input Voltage: 3V @ 1kHz w/ Reverberation time @ minimum
Harmonic Distortion: Less than 0.2% @ 1kHz w/ Reverberation time @ minimum output level 300mV
Frequency Response: 20 to 30,000Hz  +/-2dB w/ Reverberation time @ minimum & 20 to 30kHz  +/-10dB w/ Reverberation time @ max
Signal to Noise Ratio: 65dB @ output level 300mV
Reverberation Time: 1.9 to 3.2 second @ 1kHz
Input Impedance: >200kΩ @ 1kHz

Classic mid '70's Sansui, stereo "REAL" Analog, Spring Reverb. These things sound great. Add depth to your sound. Makes a room come alive. This one is in great shape. Great sounding internal, Real Analog Spring Reverb tank. Dual tape monitors with bi-directional dubbing. Record feature allows you to listen to the sound with reverb while not affecting or effecting your recording. Great looking multi-color display. Infinitely Variable reverberation time. Cosmetically, there's really only one thing to mentioned, in that the original, 50 YO wood grain, vinyl wrap has shrunk a bit exposing about 1mm of each corner joint. Unit works and looks great in near new condition.
This one actually comes with it's original box and unique, fully enclosing, Styrofoam packing. Comes with an 'e-copy / PDF download of the SANSUI RA-500 owners / users manual, and of the brochure. Unit measures 12" wide x 11" deep x 6.5" tall and weighs 12 lbs unpacked. Includes our standard 30 day limited warranty.
SANSUI RA-500
Cond. 8.5+++
$349.00
(C) R.R.

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

    

        NEW LISTING 10/4/2021
(click on above thumbnails to enlarge photos)
warranty
 PRE-OWNED
AUDIO AUTHORITY
MODEL 515
PROFESSIONAL GRADE
 A/V / AUDIO SOURCE SWITCHER / SELECTOR / COMPARATOR
MADE IN U.S.A.
for sale
Professional / commercial grade A/V source input switcher. Very easy and straight forward to use. This 'passive' unit adds 4 A/V source inputs (switches "5", but typically uses one of your existing Inputs / Tape monitors to connect to your system) to any single input on a receiver / pre-amp. Inputs may be utilized for Reel to Reels, Cassette Decks, 8-Track Decks, DAT's, CDR's, iPod's, MP3 Players, DVD Audio as well as (may also be used for Video / CD / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.
This unit also gives you Main audio Ouputs and a video output. 18 RCA jacks on rear panel! We have completely gone through the unit cleaning all switches and contacts. All of the RCA jacks are free of oxidation and shine. New silicone feet / pads installed on bottom panel. All inputs test great. These are great "tools" to have in any audio system, 'pro' or home or even a display / store situation to input 5 sources to one. Greatly enhances the versatility of most systems. The unit looks good with not much cosmetically worth mentioning (except scratches / scuffs on the bottom panel).
Slotted screw holes in top sheet metal to allow mounting under a shelf.
Measures 8" wide x 4.5" deep x 2" tall and weighs ~1.5 lb unpacked. Includes our standard 30 day limited warranty!
AUDIO AUTHORITY 515
Cond. 8.5
 $109.

    

        NEW LISTING 10/4/2021
(click on above thumbnails to enlarge photos)
warranty
 PRE-OWNED
ARISTA
"TAPE DIRECTOR" 20-800
 AUDIO TAPE MONITOR / EFFECTS LOOP / SOURCE SWITCHER / PROGRAM ROUTE SELECTOR / COMPARATOR
WITH SELECTABLE 'RECORD' OUT
& DUAL 'MAIN' OUTPUTS
for sale
Quite a versatile input source / tape monitor switcher. Very easy and straight forward to use. This 'passive' unit adds 2 source inputs (switches "3", but typically uses one of your existing Inputs / Tape monitors to connect to your system) to any single input on a receiver / pre-amp. AUX input (may also be used for Video / CD / DVD /DAT / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.) and 2 tape monitors / loops. Selects between 2 tape decks (Reel to Reels, Cassette Decks, 8-Track Decks, DAT's, CDR's, iPod's, MP3 Players, DVD Audio as well as (may also be used for Video / CD / VCR / MP3 / iPod® / iPhone® / iTouch® / iGadget / MP3 / XM® / SIRUS®  etc.) with 'Dubbing / Copy' from Tape 1>2.
This unit also gives you Dual Main Ouputs to feed two amplifiers, receivers, sound systems, computers sound cards or mixers. 16 RCA jacks on rear panel! We have completely gone through the unit cleaning all switches and contacts. All of the RCA jacks are free of oxidation and 'shine like a new dime'. Original feet / pads still intact on bottom panel. All functions test great. These are great "tools" to have in any audio system, 'pro' or home. Greatly enhances the versatility of most systems. The unit looks good with not much cosmetically worth mentioning.
Measures 8" wide x 4.5" deep x 2.25" tall and weighs ~2 lb unpacked. Includes our standard 30 day limited warranty!
"TAPE DIRECTOR" 20-800
Cond. 8.5
 $79.

    

All toggle switches cleaned (entire circuit board and patch panel must be removed to access). Cleaning ALL the toggles is a MUST-DO. Otherwise, these things are just 'paperweights'.

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NEW LISTING 9/14/2022
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CLEANED / BENCH TESTED
VINTAGE MCS VTR COMPONENT B&W WAVE FORM SCOPE / MONITOR / TV
MCS 685-T015
#...1291
Circa 1978
Made in Japan
for sale

ü Everything was completely tested and benched.

ü All controls / switches in working order

ü All potentiometers / control pots cleaned

ü All illumination functioning fine

ü We then tested both channels with multiple test tones and recorded material.

Likely be the only kid on your block with one of these. It's a cool, way to get a display of your music. 5" Monochrome screen displays in real time, the wave-form of your music / audio. Yes, it can also function as a TV, but it's analog and TV broadcasts are now digital, so...
Anyway, as it's a 30fps screen (like most TV's used to be), it's difficult to get a digital camera to capture the waveform as a 'full screen', so we took lots of photos with the screen scan in different positions. In real life, you always see a full screen of whatever wave form is being displayed.
 
MCS VTR Component Features include;

- 5" Monochrome, back-lit screen
- VHS and UHF tuner built-in (really not of much use as broadcasts are now digital)
- Appears to be able to take 'speaker level' signals, but we connected with 'Line Level' signals
- Front mounted Brightness and Contrast level controls
- Volume control for 'pass thru' audio monitor jack
- RCA Inputs for Stereo Audio L & R
- RCA mono output
- Full VHF and UHF antenna connections (again, a bit of moot point now)
- Rear mounted Vert and Horiz hold (remember those?)
- Unswitched AC convenience outlet rated to 150 Watts

Again, our tech has bench tested this unit and 'certified' it READY TO GO! Cosmetically, it's really very clean. Not really much to talk about as far as that goes. Plexi screen cover still clear with only the most minor striations. Great compliment and conversation piece and will connect to most any audio system (probably even suckie, modern A/V / surround / 5.1 / 7.1 / BR549 / Home theater systems).
Measures 16" wide x 11" deep x 5.5" high and weighs 10 lbs unpacked.
MCS VTR Component
Cond. 8+
$299. (C)
M.H.

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

 

    

         NEW LISTING 4/17/2023
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WALNUT WOOD VENEER
EQUIPMENT RACK / CASE
6U / 6-SPACE
for sale
This came in loaded with vintage Crown equipment. I could be from Crown, or could be from another mfg. It will, of course fit standard / 19" width rack gear from any company. Solidly built. Click here for link to page with full info....



 

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NEW LISTING 7/11/16
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  warranty
VINTAGE
PIONEER SPRING REVERB
PIONEER SR-202W ANALOG SPRING REVERB
#...1149
"WORLD AC POWER" ™
 Circa 1973-75
MIJ
SOLD 1/11/2023
SHIPPED TO ELVIS IN NORTH CAROLINA
Our technician has completely gone through and 'Certified' this unit.
Unit was disassembled for restoration / reconditioning. All switches / controls cleaned. Springs, send and receive units inspected and re-soldered where necessary. Spring suspension inspected. All display and power lamp sockets 're-sprung' and their lamps / bulbs replaced with new. All RCA I/O jacks had their solder joints re-flowed. Display 'slide' mechanism cleaned and re-lubed. Control shafts check for 'true' and straightened where necessary. AC power voltage and fuse checked for correct setting and proper value. We then tested both channels with a test tone and O-scope, analyzing both channels with and without each independent effect. It was then cleaned inside and out, then polished to look great. Floor noise measured to -60dB! Only issue cosmetically is a minor scuff on the top edge and a minor cigarette burn to the top vinyl (neither particularly distracting).
 Unit performs and sounds great!

From the original brochure, "The reverberation amplifier is one of Pioneer's unique products.  Unlike ordinary high fidelity systems that use single scatter systems, the SR-202 employs a double scatter system involving the merging and blending of two channels in a complex composite sound.  The direct signals from the pick-up that have been fed through the preamplifier, and the reverberation signals, which are comprised of the signals of the opposite channels to which reverberation effects have been added, are merged and blended to result in a composite sound that includes echoes and reflected sounds.  Two time delay circuits eliminate any peaks or dips in reverberation so what you hear is absolutely stable and has tremendous depth and brilliance.  The SR-202 reverberation amplifier can be used to increase the naturalness of your own recorded voice, radio broadcasts, records or tapes.  It can be coupled with your own system's amplifier (with tape monitor jacks) in various ways, to provide reverberation effects to the speakers only, or to just the recorded sounds, or both together.  You can even control two tape recorders at the same time by switch operation for simultaneous recording, recording with reverberation, playback etc.  In fact you can connect the SR-202 in practically any way you like for the effects you want. The system can be converted back to normal operation any time with the flip of just one switch."
 ______________________________

Pioneer SR-202W Features;

- Dual spring, Analog Reverb tank
- Prismatic, Multi-Color reverb level display
- Mechanical Depth / Reverb Time control
- Record out with Effect selector
- Dual Tape monitors
- "Bi-Directional" tape dubbing
- Dual un-switched AC convenience jack located on the back rated at 300 Watts
- Externally located main protection fuse
- Ground lug
-  "WORLD AC POWER"™  50 / 60 cycles there is a 110V, 120V, 220V & 240V selector for use anywhere in the world!

Pioneer SR-202 Original Specs:
Rated Output Voltage: 330mV @ 1kHz w/ Reverberation time minimum input level 200mV
Maximum Input Voltage: 3V @ 1kHz w/ Reverberation time @ minimum
Harmonic Distortion: Less than 0.2% @ 1kHz w/ Reverberation time @ minimum output level 330mV
Frequency Response: 20 to 35,000Hz  +/-2dB w/ Reverberation time @ minimum & 20 to 50kHz  +/-10dB w/ Reverberation time @ max
Signal to Noise Ratio: 65dB @ output level 330mV
Reverberation Time: 1.9 to 3.2 second @ 1kHz
Input Impedance: 300kΩ @ 1kHz
Output Impedance: 10kΩ @ 1kHz

 Classic mid '70's "REAL" Analog, Spring Reverb. This one is in impeccably clean shape. Again, it's been completely gone through as stated earlier. Wood grain, vinyl wrapped cabinet in great shape. Face perfect as is display window. RCA inputs and outputs for 2 tape decks.  Also features dual AC convenience outlets. All original knobs in great shape! This thing looks near NEW. Has very strong send and receive coils on the reverb tank, so you can get HUGE reverb with this one if you wish. Also great for use in your studio. All original knobs in great shape! This thing looks new. Silk-screened chart on bottom shows a variety of hook-ups. True "WORLD AC POWER"™ 50 / 60 cycles there is a 110V, 120V, 220V & 240V selector for use anywhere in the world! Comes with an 'e' copy / pdf download of the Pioneer SR-202W owners / users / operations manual. Unit measures only 12.5" wide x 9.5" deep x 5.5" tall and weighs 10 lbs unpacked. Comes with our 30 day limited warranty.
PIONEER SR-202W
Cond. 9
SOLD 1/11/2023
SHIPPED TO ELVIS IN NORTH CAROLINA

(Above text property of www.oaktreevintage.com / Oak Tree Enterprises, LLC. See 'Copyright Information' page for details)

 

NEW LISTING 7/2/10
(Click on above thumbnails to enlarge photos)
warranty
PRE-OWNED
MONSTER
"POWERCENTER"
              HTS-2500 MKII HTS2500 MK II
AC POWER CONDITIONER / SURGE PROTECTOR
for sale
We have just had our tech go through this unit. When it came in it had the Monster 'death beep' as most used one's do. He was able to
Click here for more info...

 

** "(actual as measured)" refers to original test results done by Hirsch-Houck Laboratories upon test release of product when new. Current "aged" specifications / performance may of course vary from that.