500R8 USB Audio Interface & 8-Slot 500 Series Rack

28-in/30-out USB 2.0 audio interface
Low-latency USB 2.0 interface with high-stability and compatibility with a wide range of PC/macOS devices.
ADAT I/O (16/16 channels @ 44.1/48kHz, 8/8 channels @ 88.2/96kHz)
5-pin MIDI I/O

High-performance A/D conversion
Dynamic Range: 121dB A-weighted, AES17 method, 20Hz - 20kHz
Frequency Response: -1dB, 2.2Hz to >80kHz
THD+N: <0.00032% (-110dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
Max Input Level: +24dBu

High-performance D/A conversion
Dynamic Range: 121dB A-weighted, AES17 method, 20Hz - 20kHz
Frequency Response: -1dB, <1Hz to >61kHz
THD+N: <0.0003% (-110.5dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
Max Output Level: +24dBu

Master reference-quality internal clock
Capable of 44.1, 48, 88.2, 96, 176.4, and 192kHz operation
<0.5ps of jitter
Dedicated Word Clock Input and Output via BNC
External sync options using Word Clock BNC, S/PDIF, or ADAT

Monitor controller with talkback
Speaker A/B switching, Mono check, Dim, Mute, and 28-segment peak meter
Dedicated talkback input with phantom power, push-to-talk activation, and automatic routing to all headphone and C.A.S.T. facilities
Easy-access illuminated front panel controls for all monitor controller functions.

Analogue summing mixer
8-into-2 analogue summing mixer with +26.5dBu of headroom, dedicated ADC, and balanced 1/4" jack outputs
C.A.S.T. link port for increasing summing mixer to 16-into-2 using Cranborne Audio 500ADAT

Zero-latency artist mixer
Zero-latency analogue artist mixer with physical level/pan controls per channel and DAW return blend controls
2 high-power headphone outputs with independent blend and level controls

Reference-Quality Headphone Outputs
THD+N: <0.0006% (-104.4dB) @ 20dBu, 1kHz, A-weighted, 300ohm load
Output Wattage (1kHz): 250mW x 2 @ 600 ohms, 650mW x 2 @ 220 ohms, 1.21W x 2 @ 100 ohms, 500mW x 2 @ 32 ohms
Frequency Response: 1dB, <1Hz to >70kHz

High-current 8-slot 500 series rack
250mA current per-slot with 2A total for all slots
XLR inputs, XLR line outputs, and TRS Inserts (pre-ADC) per 500 series slot
Module source switching options to send Analogue, USB or external C.A.S.T. signals through your favourite 500 series modules
Module bypass switches per-slot allowing 500R8 to be used without 500 series modules inserted.

C.A.S.T. Compatible
C.A.S.T. ports per channel for relocating analogue I/O around studio using passive or active C.A.S.T. breakout boxes via standard shielded Cat 5

24v, 5a external locking power supply
External power supply for improved analogue audio performance and heat dissipation.

Designed, Engineered, and Manufactured In The UK
Each and every 500R8 is extensively tested by a team of dedicated engineers to ensure reliability and consistency.

Please follow the button below to read the 500R8 User Manual
500R8 User Manual


Here is the comprehensive set of 500R8’s technical specifications. We try to keep our specifications as real-world measurements. Each test has been carried out in a particular way to replicate how each element of 500R8 would perform in day-to-day operation.


All specifications are typical performance unless otherwise noted. All specifications are subject to change at any time. Tested with Audio Precision APx555 at 192 kHz internal sample rate and internal clock. HF response of digital measurements will vary depending on sample rate selected during recording.
Digital Performance
A/D Conversion
Test Signal Path XLR Input - 500 Series A/D Converter - APx555 (ASIO)
Frequency Response -1dB, 2.2Hz to >80kHz
  -0.05dB, 20Hz to 20kHz
THD+N <0.00032% (-110dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
  <0.00065% (-104dB) @ -1dBFS, 20Hz - 40kHz, 1kHz, A-weighted
THD <0.00014% (-117.5dB) @ -8dBFS, 20Hz - 40kHz, 1kHz, A-weighted
  <0.00023% (-113dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
  <0.0006% (-105dB) @ -1dBFS, 20Hz - 40kHz, 1kHz, A-weighted
Dynamic Range 121dB A-weighted, AES17 method, 20Hz - 20kHz
Max Input Level +24dBu
D/A Conversion
Test Signal Path 500 Series D/A Converter - Insert Send - APx555 (ASIO)
Frequency Response -1dB, <1Hz to >61kHz
  -0.05dB, 20Hz to 20kHz
THD+N <0.0003% (-110.5dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
  <0.0004% (-108dB) @ -1dBFS, 20Hz - 40kHz, 1kHz, A-weighted
THD <0.00014% (-117.5dB) @ -8dBFS, 20Hz - 40kHz, 1kHz, A-weighted
  <0.00018% (-115dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
  <0.00036% (-109dB) @ -1dBFS, 20Hz - 40kHz, 1kHz, A-weighted
Dynamic Range 121dB A-weighted, AES17 method, 20Hz - 20kHz
Max Output Level +24dBu
Jitter <0.5ps
Analogue Performance
Line Outputs (Speaker B, Aux, Mix)
Test Signal Path DAW 2 D/A Converter - Line Outputs - APx555 (Line In)
Connection Type 1/4" Jack, Impedance Balanced
Output Impedance 150ohm balanced, 75ohm unbalanced
Max Output Level <+22dBu
Freq Response -1dB, 1.4Hz to >80kHz
THD+N <0.003% @ +18dBu, 1kHz
Dynamic Range 105dB A-weighted, AES17 method, 20Hz - 20kHz
Noise Floor <-93dBu A-weighted, 20Hz - 20kHz, (Unity Gain)
Speaker A Output
Test Signal Path DAW 2 D/A Converter - Speaker A Line Output - APx555 (Line In)
Connection Type XLR, Balanced, non-floating
Output Impedance 150ohm balanced, 75ohm unbalanced (pin 3 unconnected)
Max Output Level <+26dBu
Freq Response -1dB, <1Hz to 70kHz
THD+N <0.0016% @ +24dBu, 1kHz
Dynamic Range 109dB A-weighted, AES17 method, 20Hz - 20kHz
Noise Floor <-92.5dBu A-weighted, 20Hz - 20kHz, (Unity Gain)
Talkback Input
Gain 30dB Fixed Gain Preamp, +20dB Analogue Trim
Phantom Power Always On
Summing Mixer
Test Signal Path XLR Input - Summing Mixer Bus (Unity) - A/D Converter 9/10 - APx555 (ASIO)
Freq Response -1dB, 2.25Hz to >80kHz
  -3dB, 1.2Hz
  -0.5dB, 3Hz
THD+N <0.0007% @ +23dBu (-1dBFS), 1kHz
THD <0.0003% @ +14dBu (-10dBFS), 1kHz
  <0.0004% @ +20dBu (-4dBFS), 1kHz
  <0.00055% @ +23dBu (-1dBFS), 1kHz
Dynamic Range 108dB A-weighted, AES17 method, 20Hz - 20kHz
Noise Floor (A/D 9-10) -108dBFS A-weighted, 20Hz - 20kHz
Max Contribution Level +28dBu
Pan Law -4dB
Noise Floor (Mix Output) -90dBu, A-weighted, No channels routed
  -89.5dBu, A-weighted, 1 channel routed (Unity)
  -84dBu, A-weighted, 8 channels routed (Unity)
Headphone Amp
Test Signal Path DAW 2 D/A Converter - Headphone Output - APx555 (Line In)
Frequency Response -1dB, <1Hz to >70kHz
THD <0.0006% (-104.4dB) @ 20dBu, 1kHz, A-weighted, 300ohm load
THD+N <0.00085% (-101.4dB) @ 20dBu, 1kHz, A-weighted, 300ohm load
Output Impedance 0.33 Ohms
Output Wattage 250mW x 2 @ 600 ohms, 1kHz
  650mW x 2 @ 220 ohms, 1kHz
  1.21W x 2 @ 100 ohms, 1kHz
  500mW x 2 @ 32 ohms, 1kHz
Dynamic Range 114.5dB A-weighted, AES17 method, 20Hz - 20kHz, 300ohm load
Noise Floor -93.5dBu A-weighted, 20Hz - 20kHz, 300ohm load
System Performance
Analogue Path Phase Performance
Test Signal Path XLR Input - Empty 500 Series Slot - Summing Mixer Bus (unity) - Monitor Bus - Speaker A Output - APx555 (Line In)
Phase <3.6° @ 20Hz, <22° @ 20kHz
Test Signal Path XLR Input - Empty 500 Series Slot - Summing Mixer Bus (unity) - Mix Output - APx555 (Line In)
Phase <1.5° @ 20Hz, <11° @ 20kHz
Test Signal Path XLR Input - Camden 500 Preamp (Mic Mode, 6dB Gain) - Summing Mixer Bus (unity) - Speaker A Output - APx555 (Line In)
Phase <3° @ 20Hz, <13.5° @ 20kHz (Preamp mic mode, 6dB Gain)
Digital Round-trip Performance
Test Condition 500 Series D/A Converter - 500 Series A/D Converter - APx555 (ASIO)
Dynamic Range 118dB A-weighted, AES17 method, 20Hz - 20kHz
THD+N <0.0004% (-108dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted
AC Requirements 100V – 240V AC, 50 – 60 Hz
Total Power Consumption 24v, 5A DC, 120w
500 Series Slot Current 250mA per rail
Total Available 500 Series Slot Current 2A
Operating Temperature +1 to 30 degrees Celsius
Storage Conditions -20 to 50 degrees Celsius
Width 481mm(19"), Rackmount
Height 185mm(7"), 4u
Depth 219m(8.6")
Unit Weight 7kg
Shipping Carton
Width 550mm(21.7")
Height 280mm(11")
Depth 335m(13.2")
Weight 7.5kg

Please download the latest drivers below for your 500R8 to operate on Windows devices. 

Download Driver (Windows)

*Driver compatible with Windows 7, and Windows 10.

500R8 is class-complaint on macOS and does not require drivers to operate.

Studio In A Box

500R8 is home to 8 of your favourite 500 series modules. It's also a 28in/30out USB audio interface, monitor controller, and discrete analogue summing mixer.

Analogue Character

Configure 500R8 to suit your desired analogue flavour. Fill it full of vintage-style 500 series preamps when you're recording drums, clean and pristine preamps when you're recording strings, or EQ/Compressor/saturation 500 series modules when it's time for mixing. 
...Meets Digital Precision
Connect 500R8 directly to your PC/Mac and capture every last nuance of your analogue sources with reference-class AD/DA conversion and superior internal clocking. Effortlessly pass audio between analogue and digital worlds without digital artefacts that colour and degrade your recordings. 

Sound On Sound

"...500R8 measures extremely well... easily on a par with the best standard USB interfaces currently on the market."

"it’s a top-notch audio interface, a capable 500-series host chassis, an expandable analogue summing mixer, and more besides”

"...they have a right to be very proud of this flagship product."

"The bottom line is that this melting-pot of an interface is a genuine triumph"


Read More


The Studio Essentials

500R8 has everything you need to build your dream analogue/digital hybrid studio. Each element has been carefully considered and designed to give you best of everything combined into a package that is intuitive (and fun) to use.


USB Audio Interface
Connect directly to your PC/mac via USB and utilise 500R8's built-in 28-in/30-out USB audio interface for recording and playback directly to/from your chosen DAW.


Monitor Controller
Switch between two sets of speakers, toggle Mono sum, Mute, Dim, and Talkback facilities whilst monitoring the peak level of your mix with 28-segments of LED detail by using the built-in, high-headroom monitor controller.


Zero Latency Artist Mixer
Monitor live sources in the analogue domain with zero latency by using dedicated mix level and pan controls per-channel combined with our seriously high-powered headphone amps.

Discrete Summing Mixer
Elevate your mix with analogue character and sum 8 USB sources through your 500 series modules and into the discrete analogue summing mixer to be summed and recorded back into your DAW as a stereo track.

500R8 Quick Tutorial Videos


World-Class Conversion & Clocking

To make your 500 series modules shine on your digital recordings, our conversion had to be best-in-class. We squeezed every possible .1dB of performance out of 500R8's converters to ensure that the only thing colouring your recordings are your mic placements, mixing decisions, and choice of 500 series modules.

Dynamic Range:
121dB A-weighted, AES17 method, 20Hz - 20kHz

Frequency Response:
-1dB, 2.2Hz to >80kHz

<0.00032% (-110dB) @ -4dBFS, 20Hz - 40kHz, 1kHz, A-weighted

Clock Jitter:
<0.5 Picoseconds


Deep 500 Series Integration

Configurable Front End
Mix and match your 500 series modules to find the best combinations during recording, and mixing to help create your own signature, analogue sound.

Source Select
Re-patch your 500R8 at a flick of a switch. Dedicated source select switches for each 500 series slot adjusts the signal routing to send Analogue, C.A.S.T. or USB sources through each your modules.

Enough I/O For Any Hardware
500R8 to integrates with all of your analogue/digital hardware. Patch in 500R8 with your own converter or integrate your 19" rack gear with dedicated TRS insert jacks per slot.

No Modules? No Problem
Bypass unused 500 series slots using 500R8's dedicated slot-bypass switch and you can use all of the available analogue paths for recording whilst you continue to build your 500 series collection.

Tape Op

"...it truly is a very well thought out mini-studio that packs a ton of punch has loads of versatility and expandability"


"Every "studio-head" friend that comes by and sees the unit is immediately intrigued and impressed by its sonic, form factor, and capabilities"


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Mix Magazine

"...this is one impressive piece of kit"


"Despite such broad functionality it's surprisingly user-friendly and intuitive, not to mention reasonably priced."


"...the sound quality is stellar...Cranborne Audio did a great job of designing its feature set that's both practical and comprehensive"


Read More

Ready For More?

When you've run out of available recording channels on 500R8, our 500ADAT comes to the rescue. Connect 500R8 and 500ADAT together via ADAT and now you have 16 channels of 500 series modules to work with. during recording and mixing. Whilst 500ADAT offers the same performance as 500R8, any 3rd party ADAT expander is also compatible.

More Recording Channels
Record up to 16 channels directly through independent 500 series modules and directly into your DAW for processing. 

More Summing Channels
Play back instrument groups/stems into all 16 available 500 series slots for summing using our C.A.S.T. link connector.


C.A.S.T. Away

Fitted with our C.A.S.T. system, 500R8 casts-away excess cabling spaghetti and offers a cost-effective, low-maintenance, plug-and-play solution by transporting 4 channels of balanced, analogue audio over shielded cat 5 cable directly to the location where it is needed in your studio.

Receive Audio From C.A.S.T.
Connect 500R8 to our N22/N22H breakout boxes using shielded cat 5 cable and now you can send mic/line sources through 100m of Cat 5 cable and directly into 500R8's module inputs.



Transmit Audio To C.A.S.T.
Through that same cat 5 connection, you can transport 500R8's monitor mix (with Talkback included) through C.A.S.T. and directly to the musician at the other end zero-latency analogue monitoring.



Home Grown Designed, Engineered, and Manufactured In The UK

Housed in a 4U, 19" rack mountable steel frame, 500R8 lends it self perfectly to mobile recording setups. We tried to think of everything, even the rack ears support three unique mounting methods. You can recess 500R8 into the rack to protect the front panel controls during travel; you can also take those same rack ears and re-orientate them to become a carry handle.

Home Grown
500R8 is designed, engineered and manufactured in the UK. Every unit that leaves our UK factory is thoroughly tested to provide years of trouble-free and dependable service.

Built And Designed With Passion
We don’t take shortcuts. We don’t compromise. We don’t accept “good enough.” We’re just like you. We’re musicians. We’re audio engineers. 500R8 is a product we're very proud of, and we hope you will be too.

The Cranborne Audio Family

"The R8 is a recordist's dream, but for me I recognised that it was also going to be the perfect centrepiece for a hybrid mix setup, and it hasn't disappointed.

The guys at Cranborne have managed to produce something that not only sounds phenomenal, but is also extremely intuitive and fluid in use.

The flexibility of this unit is second to none, with a myriad of routing options available at the flick of a switch or the turn of a knob.

As soon as you start using it, it's obvious that this is a product designed by people that as well as being at the top of their game in terms of technical know-how, also work with music day in, day out,
and every feature has been put there in order to make getting a great end result fast and easy.

Great product, great people behind it, ridiculous price for what you get, what more can you ask for?!"

Matt Ransley

“…It's a beautiful piece of kit and my seven year wish of having an ADAT I/O enabled 500-module rack has finally come true."

"I mainly intend to use the 500ADAT as an outboard effects loop for my DAWs. 500ADAT is being used (via its ADAT I/O) to route a master drum track out to a pair of DIYRE Colour modules and then through a stereo pair of Radial EXTC's to add some dub-style echos via a Strymon Volante pedal."

"It sounds excellent and is exactly the type of workflow I've been wanting to use with my growing collection of pedals and outboard. Best of all it makes everything very hands-on and tactile which lends itself to mixing with my ears rather than with my eyes. Great stuff for getting out-of-the-box!"

"Thanks again for seeing this journey through to completion and for filling a much needed niche with the 500ADAT. It's going to get a ton of use here in my home studio!..."

W Todd Reynolds

"So we just ran a quick test with R8+camden against a Scarlett. Not scientific or anything, but holy sh*t is there a big difference."

"Added a bit of mojo and the vocal sounded pretty much done. It actually sounded like it was EQ'd and compressed, like a final track pretty much."

"I'm more than happy! Can't wait to get a real session going."

Jukka Lariola