Audio Proz Service and Sales


Nakamichi CA-7A

Audio Proz Inv #: 62855

Control Amp. (2) Phono in with selectable MC/MM, 3 position cartridge loading switch, and 3 position gain selector. Tuner, CD, Aux 1 and 2 inputs. (2) Tape loops, and (2) set main RCA outputs. (Has some DIN connectors for Tape, CD, Tuner). Complete cleaning and serviced by AP. No remote, Missing (2) function selector gap covers. #8 condition. Missing (2) Function selector gap covers for CD and Tuner

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Adcom GTP-500 II

Audio Proz Inv #: 62179

AM/FM Preamp (Preamp with built in Tuner). NO REMOTE. 6 db gain change at output circuit. Low noise for headphone out. Used excellent condition, modified unit for better nicer range on volume control. #9 condition

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APT Preamp Faceplates

Audio Proz Inv #: 63434

Pebble Black Finish, various available. One (1) in #9 Condition- $68. Six (6) more available in various conditions, all good with no major damage, approximate #8+ condition -$46.

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Kenwood L-07C

Audio Proz Inv #: 63147

Stereo Control Amplifier. High accuracy EQ. GMN Stage volume and level control for a very high gain low noise FET gain, low noise FET Design. Audiophile phono pre MC and MM. Cleaning, glue removal, and board resoldering done. Low use #8+ condition SUPER LOW NOISE!, Condition #8+

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Adcom 6FP 555 II

Audio Proz Inv #: 63473

Basic preamp. Top quality phono (with correct ground layout)! Audiophile tone controls, only accent extreme high and low. 5 inputs, bad obvious light scratch at switch, #8- condition. 

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Local customers, please do not come to the shop without calling ahead first - (617) 926-8020 - for an appointment, so that we can more efficiently help you with your equipment or sound recording needs.

We keep our database up to date with almost 10,000 items in stock. If you see a part number and a price, we have that item in stock. 

Customers outside of the US, please note that international shipping can be costly (US Post $16 minimum - up to 8oz or 226g). We are glad to combine orders to reduce shipping costs. Take a look at our shipping policies for more information and estimates of prices and shipping time.


Apt Holman Pre Amp Modified Level III

Audio Proz Inv #: 63530

Top Quality Hi accuracy, very well built product. Complete service , clean and calibration. Inputs: Phono 1 and 2 , tuner, Aux1 and 2, Tape 1 and 2   (Dubbing 1>2  2>1) Level 3 modification by AP.  See description herehttps://www.audioproz.com/AP.php?Article=95   #8+ condition Minor scuff on face panel.

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Luxman 5C50

Audio Proz Inv #: 70414

Super Quality Preamp, Much class  circuit design, (2) new upgrade quasi op amp circuit for phono section. (2) other modules (original) have been opened and re-soldered mini circuit board, double up on Mylar preamp coupling caps. Excellent Noise Floor, MC transformer installed type 8020 40ohm load. Most caps replaced in power supply (small value types) All calibrations done for preamp module D.C. offset, new status bulbs. case and cover has few minor scuffs, Face is #9 Very low use machine #8+ condition

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Adcom GTP-450

Audio Proz Inv #: 70494

AM/FM tuner/preamp. 14 presets. Bass/Treble + Balance Controls. Inputs: CD, Tuner, Tape/Tape 2, Aux. External processor loop. 1/4" headphone jack. Remote control RC-45 included. FM aligned and glue removed. #8 Condition. Note: No phono input.  

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NAD C162

Audio Proz Inv #: 70757

Fancy high preamp. Class A module design. Slimline design. Bass/treble controls. MM, MC input. Headphone out. Unit does indeed have little more clarity in over all design (subtle). Some power supply upgrades of crucial resistor and rugged resoldering. #9 condition.

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Apt Holman Preamp 2

Audio Proz Inv #: 71499

Serial number J81E223. Level III mod, upgraded: all P.S. caps, all audio caps, headphone op amp, phono EQ circuit. AP correctly updated unit. Condition 9

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Dynaco PAT 5

Audio Proz Inv #: 71763

Light Gold/Silver Faceplate, Back panel RCA perfect, low phono noise level excellent, Absolute mint condition original, no mods, low use, Excellent quality Assembly, #9 Condition

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We leave "SOLD" items on our website for machines that we often repair and provide parts for. This is to give you an idea of the products we typically carry, and direct you to alternatives you may not know about - we often have substitutes for out-of-stock parts, and are happy to recommend workarounds and different solutions to common problems.


Apt Holman Preamp

Audio Proz Inv #: 71851

High Quality Reference standard pre-amplifier byTom Holman.  This is a stunning looking preamp with a new black pebble face panel and grey knobs- very sharp and Vinces favored look! .  Complete Level III modification which includes : All power supply caps upgraded, Audio caps upgraded, relay updated, headphone amp FET spec. All modification to Phono, EQ, Tone control circuits as well as infra filter. Excellent condition #9 

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Apt Holman Preamp

Audio Proz Inv #: 71840

Complete level III update, Rack face, no handle. Minor bends and dents at one rack hole. Slight bend at each side. Flat matte black face. Lettering is perfect. . SN: 2527, but has later version boards. Unit can have another face installed, call. Condition #9.  See about Level III mods here. https://www.audioproz.com/AP.php?Article=95

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Marantz 3200

Audio Proz Inv #: 72101

Vintage preamp, silver face with black inset, bass / mid / treble controls with turnover 250hz 4kHz, phono 1 / 2, tape 1/ 2, tuner, aux inputs, *back panel RCA's have been replaced (metal plate was cut to fit new RCAs), fully serviced, excellent condition, all basic service, condition #9

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Krell KRC-3 Stereo Preamp

Audio Proz Inv #: 72609

(1) Stereo Balanced XLR, (2) Stereo Line Inputs, (1) Stereo Line/processor, (1) Stereo Line/tape, (1) Tape out RCA's L/R  Main Outputs RCS and XLR, Super Quality, NO REMOTE / NO PHONO, with photocopy of owners manual, Condition #9

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Apt Holman Preamp

Audio Proz Inv #: 72666

Audio Pro Modified Level III, Nice low use unit , Ground mods, tone control mods, headphone amp mod, All necessary capacitors replace & phono filter, Relay cleaned & tested, RFI mods. Only minor wear on face and top cover #9- condition

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Marantz Model 3200 Stereo Control Console

Audio Proz Inv #: 72678

Headphone out, hi-filter, montor source/ tape, left/right balance slider, bass/ mid/ treble sliders, loudness, tone mode selection. Beautiful unit in excellent functional and cosmetic quality. Better version electronics (tantlum caps). Clean face with minor signs of use. Aftermarket feet installed on bottom. #8+ Condition

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Need an APT unit serviced or modified? Vince, the owner of Audio Pro, ran the production line at APT for many years, and has decades of experience working with APT products. Read all about our APT Holman service and mods here. Also read about the APT Moving Coil Phono Mod Here.


MCM Model 40-630 Solid State Stereo Phono Pre-amplifier

Audio Proz Inv #: 70434

Basic phono preamp, 1 stereo input, 1 stereo output, Black case (4"x2.5"x1.5"), Good condition (#9)

$ 14  Contact Us  

GOgroove Phono Preamp

Audio Proz Inv #: 63220

Basic phono to line level w/ RIAA equalization, RCA / 1/4" TRS output (line level), 12v DC power supply included, Small and compact (4"x2.75"x1.25"h), Original box and manual, Used in Excellent condition #9

$ 18  Contact Us  

A-PA1 Solid State Stereo Phono Pre-amp

Audio Proz Inv #: 27173

Stereo Phono preamp.

$ 24  Contact Us  

Behringer Microphono PP400

Audio Proz Inv #: 53914

Stereo phono preamp. New.

$ 38  Contact Us  

Ampex phono preamp 4010097-01

Audio Proz Inv #: 48142

Phono preamp with RIAA equalization. (This is a Mono Device) , Uses 8-pin socket connector. (1 only) Excellent #9 condition.

$ 38  Contact Us  

Behringer V-Tone Guitar GDI21

Audio Proz Inv #: 53921

Guitar amp modeler/direct recording preamp/DI box. New.

$ 48  Contact Us  


Need an APT unit serviced or modified? Vince, the owner of Audio Pro, ran the production line at APT for many years, and has decades of experience working with APT products. Read all about our APT Holman service and mods here. Also read about the APT Moving Coil Phono Mod Here.


ART DJ PRE II

Audio Proz Inv #: 61866

phono preamplifier, variable preamp gain, RCA outputs, new in box, OUR RECOMMENDED PHONO PREAMPLIFIER! #10 condition

$ 68  Contact Us  

dbx Mini-Pre

Audio Proz Inv #: 42401

Mint condition, single channel design with 12AX7 vacuum tube, -20db pad, phase switch, and 48v phantom supply. Peak and power LEDs. 60dB gain and -infinity to +10dB of output level. XLR microphone input, 1/4" TS line input, balanced 1/4" TRS and XLR outputs Table top design, very portable.

$ 70  Contact Us