In 2004 Yamaha debuted the AD8HR AD Converter. The 8-channel AD8HR provides head amplifier circuitry inherited from the acclaimed Yamaha PM5000 analog mixing console and supports sampling rates of up to 96kHz. Up to 255 of these chonky blue boys can be daisy-chained together using a standard 9-pin RS422 and provide digital out via AES/EBU. All this could be had for the low low MSRP of $2,200. While that might sound pricey it was a bargain compared to offerings from Aphex, Grace, Rocknet and others.
In 2021 you can yoink a used AD8HR for a under $300 and that got me thinking. Can I find a way to get it working with Linux for under a $1000? This is my story.
DB25 / DB9 wiring:
Wiring diagram: In this configuration we’re able to get two channels in/out from the AD8HR. The two channels in are used for clocking.
|Sampling frequency rate||Internal||“44.1kHz, 48kHz, 88.2kHz, 96kHz “|
|External||44.1kHz/88.2kHz (-10%) – 48kHz/96kHz (+6%)|
|Total harmonic distortion||Less than 0.01% (20Hz-40kHz)|
|Frequency response||0, +1, -1.5dB 20Hz-40kHz|
|Dynamic range||AD+DA: 110dB (Use DA824 for output)|
|Hum & noise level||Equivalent input noise||-128dBu (Use DA824 for output)|
|Power requirements||Depend on area of purchase; AC100V, 120V or 220-240V; 50/60Hz|
|Power consumption||35 W|
|H||45mm; 1-3/4in (1U)|
|Net weight||5kg; 11lbs|
|Accessories||Owner’s manual, AC Cable, 4x Rubber Foot|
There’s no kill like overkill and the Yamaha AD8HR is exactly that for my little studio. It’s genuinely in a different league compared to my Golden Age, Focusrite, Presonus, ART, Apogee, and MOTU preamps. If you’re comfortable Macgyvering cables and have an interface that accepts AES/EBU it’s an absolute steal at $200.
Now get out there and make something awesome.
-63 dB gain.
Banked phantom power.
High Pass filter.
No combo jacks.
No analogue outputs.