PC AV Tech Sound Card Report: HT 1869 Also Known As CM 8330

HT 1869 also known as CM 8330

Summary
Parameter	My Opinion	Mode of Operation
Parameter	My Opinion	Full Duplex Loop Back	Analog > Digital	Digital > Analog
Frequency Response	Poor	55-6.5kHz +0/-3 dB	30-16kHz +0/-3 dB	30-12kHz +0/- 3 dB
1 kHz Total Harmonic Distortion	Very Poor	2.5% @ -1.2 dB	0.63% @ -0.9 dB	1.8% @ -0.2 dB
Signal to Noise Ratio	Very Poor	24 dB	28 dB	33 dB
19 & 20 kHz Intermodulation Distortion	Very Poor	7%@-23 dB	Bad	7% @-10 dB
Dynamic Range	Good	62 dB	69 Db	77 Db
Jitter Distortion	Very Poor	Bad	Bad	-20 Db
Software Used:	Windows 95 950B; Driver Releases: WSS- 4.10.01.30, SB16 - 4.10.01.32 SB16

Technical TestDiDiscussion of Results

This card is unusual in that it is full-duplex because it has independent simulations of two different kinds of half-duplex hardware - the Windows Sound System (WSS), and the Sound Blaster 16. I found that the best-performing combination was SB16 output and Sound System input. I've tested PCI and ISA implementations of this chip and their audio performance seems to be about the same. These tests were done on the ISA version.

The HT 1869 also has very limited digital I/O. In its ISA implementation, it requires a specific ISA clock frequency to work at all. While I've worked with a number of implementations of the HT1869, including one that appeared to have an input buffer, I've never seen the digital input work with a CD ROM's digital output, which seems to be the intention. The digital output does work, but its performance is no better than the analog output, which is to say it is not useful to many who are looking for a sound card with a high quality digital output..

HT 1869-CM 8330 Sound Card Frequency response (Full Duplex - Loop Back)