Cosecant USB DAC v3 with 6GM8/ECC86 tube transformer output and upgradable DAC modules.

The Cosecant is where it all started @ CES 2004. At first Gordon Rankin did not think this technology would work.... was he wrong! The Cosecant v3 connects the USB controller to a DAC module connector. The USB firmware to run that dac module resides there so each module has it's own developed code. The output of the module connector is sent directly to the 6GM8/ECC86 dual triode output tube which drives the transformer coupled output. The Cosecant has an external power supply with IEC connector to isolate the power from the DAC and it's audio transformers. The Cosecant is also available with an optional volume control if you want to control your entire system from the computer output.

Gordon Rankin himself on the Cosecant:
The Cosecant is one of the coolest ideas I have in a long time. This allows your computer to be converted into a media central unit. That's right you can use the computer to play CD's in the CD drive. Or move songs to the hard drive and create play lists. Or you can stream music off the internet, play movies the list goes on.
One of the reasons this works so well is because ounce the track is ripped (copied) to the hard drive error free it just sounds better than any transport available.
The Cosecant does not use a USB DAC chip. It instead uses a non up/oversampling multibit dac with out the use of analog or digital filtering. The idea that what is on the disk is exactly what is going out without any math involved between disk and output.

Steven R. Rochlin on the Cosecant's inside:
Care is taken with the critical power supply as the outboard unit employs Linear Technologies regulators and Hexfred Rectifiers. A grand total of 22 Black Gate capacitors are in the Cosecant. Black Gates are longtime favorites of DIY'ers and can be found in some of the world's best gear.

Cosecant listening impressions from Dr. Jules L. Coleman:
I just finished playing all four disks of the Stiff Box collection and the music bounced when it was supposed to, the guitars jangled, the singers mumbled and stumbled just like I remember them doing when I listened to the same box set on the Reimyo. Horns have the right burnished tone, stand up basses display string and body in just the right combination, and the piano tone is absolutely first rate.

In the summary of the Cosecant review, to cut it short, Dr. Jules L. Coleman says:
...damn fine offering it is. So good, in fact, that I bought the review piece.
more...

Another opinion by Steve, author of Crimson review on Computer Audio Asylum:
The Cosecant’s strongest virtue was its balance or sense of neutrality. It basically got the timbre of the instruments correct. It was extremely musical in its presentation with a wide soundstage.


Cosecant comes standard with Transcendental 16/44.1 DAC Module. It may also be ordered with optional Numerator 24/96 DAC Module.
DAC modules are easily replaceable so you may also want to order an extra DAC module to experiment and find the best for your musical taste and requirements.

Wood options are Walnut, Cherry and Figured Maple.

Package includes the converter itself, power supply unit and high grade USB cable.