HardSID 4U "a HardSID... for you!"

The HardSID 4U is the most powerful SID synthesizer since the legendary C64!

Two CPUs and main memory
USB connection (compatible with both 2.0 & 1.1)
Isochronous USB endpoint for low-latency audio
VSTi interface with 8000Hz update rate on all SID registers (free)
Wave-in VSTi pin for routing 8000Hz signals to any registers (example: playing other VSTi's sound on the volume register)
Full automation of all VSTi parameters
Superior sound quality (..it is a HardSID!)
Support for up to four SID chips (6581/8580/6582 in any combination)
Updateable firmware over USB
Microsoft Vista compatible (drivers for Win2000/XP/Vista)

Cycle-accurate playback of your favorite SID tunes
Digitized sound + high-speed playback with low CPU utilization
Seamless playback of .sid tunes while you work on your PC by providing a huge playback buffer for non-VSTi applications
Supported by the HardSID 4U Winamp Plugin! (seeking, sub-tune handling, IR remote controlling)

Full physical separation of the SIDs from the USB driven circuits
100% elimination of EMI (Electromagnetic interference) noise that may come from your PC via USB

Many PC parts (sometimes the USB controller itself) are generating electromagnetic interference (EMI) which travels through the USB cable into your USB Audio device (HardSID 4U in this case). Even if you use a cable with built-in EMI suppression some of the noise will work its way through to your audio device. So, if any part in your PC isn't properly electromagnetically shielded, the EMI noise will be audible when low level audio is played. EMI noise can not be perfectly removed by any suppression method except by expensive physical separation of circuits connected to the PC from the audio circuits.
Suppressed EMI noise is still perfectly acceptable for hobby usage, but if you're planning to record your work/art in studio quality, you should consider going for the HardSID 4U Studio Edition, since it physically separates your audio circuits from the ones connected to your PC. We're using expensive technologies to replace direct electrical contacts between the PC driven circuits and the audio circuits.

Four mono dry outputs for the best sound quality (2x stereo jacks)
Mixed output for the easiest usage (1x stereo jack - mono signal)
Four mono inputs for filtering external sources with SID filters (2x stereo jacks)
USB connector for connecting the unit to a desktop PC or a Notebook
DC-in connector for connecting the power supply (1A@12VDC)