200/500 Series
API Select
Virtual Console Experience
Where to Buy
505-DI Direct Input
512c Mic Preamp
512v Mic Preamp
525 Compressor
527 Compressor/Limiter
529 Stereo Compressor
535-LA Line Amplifier
550A Equalizer
550b Equalizer
560 Equalizer
565 Filter Bank
V10 Single Channel Mic Pre
V12 Single Channel Compressor
V14 4 Band Equalizer
A Designs • EM-PEQ
• EM Blue Mic Preamp
• EM Gold Mic Preamp
• EM Red Mic Preamp
• EM Silver Mic Preamp
• P1-500 Mic Preamp
RPQ 500, Single channel mic pre
Analog Allstars
EQP-1S5 Passive Equalizer
A Pre 500 mic pre
COMP 500 optical compressor
EQF 500 three band semi-parametric EQ
EX•BB 500 Aural Exciter and Optical Big Bottom
J Pre 500 mic pre
Audified • Synergy R1
Audio Maintenance Limited • 5003d Mic Preamp
Avedis Audio Electronics • E27 3 Band Equalizer
BoZo Electronics • MPA3 Mic Preamp
Buzz Audio • Elixer Mic Preamp*
DACS • MicAmp 500
Daking Audio
500 Compressor
EQ 500
Mic Pre 500
Danfield • MX20 Mic Preamp
dbx • dbx 510
• dbx 520
• dbx 530
• dbx 560A
• dbx 580
Electrodyne • 501 Mic Preamp
• 511 2 Band Equalizer
elysia GmbH
karacter 500, Class-A Stereo Saturator
mpressor 500, Discrete Class-A Compressor
Nvelope, Discrete Class A Stereo Impulse Shaper
skulpter 500, Discrete Class-A Preamp
xfilter 500, Stereo EQ
xpressor 500, Discrete Class-A Stereo Compressor
Empirical Labs • DerrEsser Model EL-DS
FiveFish Audio • Janus Active DI/Shift EQ
• MX5-mk500 Mic Preamp
• PEQ-503 Equalizer
• SC-501 Mic Preamp
• X-12mk500 Mic Preamp
• X-72mk500 Mic Preamp
Forsell Technologies • SMP-500
Grace Design • M501 Mic Preamp
Great River Electronics • Harrison 32EQ
• MP-500NV Mic Preamp
Heritage Audio • 1073/500 Channel Amplifier
Inward Connections • EQ2P
JCF Audio • Levr Summing Amplifier
J-Lab Studio Electronics
JLA3 Transformer Balanced Optical Leveling Amplifier
Kush Audio
Electra 500 - Electrified Transient Equalizer
LaChapell Audio • 583s Mic Preamp
Maag Audio • EQ4 Equalizer
• PREQ4 Mic Preamp
Mooktronics Research • PDI 500
Nixer, Ltd. • London Mic Amp NIX00205
• Broadway Mic Amp NIX00220
• Vanguard Mic Amp NIX00230
Pete's Place • BAC-500 Compressor
Phoenix Audio LLC
DRS-EQ/500 Mono 4 band EQ
Rascal Audio
Two-V, dual-channel microphone amplifier
Roll Music Systems, Inc.
Tubule RMS5A7, Microphone Preamp
Safe Sound Audio • P501 Audio Processor
Shadow Hills Industries
Dual Vandergraph Stereo Compressor
Skibbe Electronics • 736-5 Mic Preamp
SMG Productions, Inc. • Channel Strip 500 CS-D
S&M Audio • EQSM1
Speck Electronics • ASC-V Equalizer
True Systems • pT2-500 Precision Mic Preamp
XQP • 531A Optical De-esser
• 535 Program EQ
• 541 Optical Compressor
• 545 Optical Disrupter
• 570 Mic Preamp
• Lima 704 Program EQ
* Maximum 2 units recommended per lunchbox
API Audio's VPR Alliance

API Audio's VPR Alliance is a program of standardization and consistency guidelines for approved manufacturers wishing to design products for API's 500-series rack format. The program provides complete design specifications for manufacturers interested in producing third-party modules that physically fit and electronically conform to API's rack specifications.

The creation of the VPR Alliance was encouraged by the overwhelming popularity of API's 500-series racks, including the 10-space 500V and the six-space lunchbox®, which led to a proliferation of third party modules that fit the API format. Typically installed into API racks, these third party modules had raised issues of warranty and interaction with API-manufactured modules in the same rack.

Because of the variables related to those third party modules, API had previously been forced to declare that inserting any third-party modules into a 500V or lunchbox voided the warranty on that rack. Through the VPR Alliance, API is now able to eliminate confusion as to which third-party products definitively do and do not void the API warranty. The VPR Alliance is a straightforward resolution that saves the company time and money while promoting goodwill to API customers.

Our customers benefit from the VPR Alliance with the knowledge of exactly which products are approved for placement in API racks; customers have a wider range of module choices for their racks that have been tested by API staff for specification compliance.

VPR-approved manufacturers benefit by earning the right to sell API racks and power supplies at dealer pricing to support sales of their products. Alliance membership additionally eliminates third-party research and development costs and production expenses associated with creating an alternate rack solution.

Members can further benefit from the exposure API generates by promoting the VPR Alliance through the strength of the company's various advertising, marketing and public relations channels, including the listing of all members on API's website. Members are encouraged to reciprocate by displaying the VPR Alliance logo on product information, public relations materials and websites.

Manufacturers wishing to join the VPR Alliance should contact API's managing director, Gordon Smart ( for a program application. If approved, API will send the manufacturer copies of the 500 Module Series Specifications and instructions on the review process. Additionally, members will receive recommendations regarding competitive issues and pricing guidelines.