There have been various families of Yamaha audio controllers labelled as YMF7xx. OPL3-SA families YMF701 (OPL3-SA): Incorporates OPL3 and OPL3-L features, 16-bit stereo CODEC, MPU-401-compatible MIDI interface, game port, Plug and Play ISA interface, Windows Sound System (CS4231) and Sound Blaster Pro compatibility. YMF711 (OPL3-SA2): Based on OPL3-SA, it adds Plug and Play ISA compatibility, 10-pin interface supports 16-bit port address decode (top 4 bits), EEPROM interface, Zoomed video port, CPU and DAC interface for OPL4-ML, modem interface, or IDE CD-ROM interface. YMF715 (OPL3-SA3): Based on OPL3-SA2, the OPL3-SA3 family adds 3D audio support via DirectSound3D and QSound. DS-XG family The last model number for controller chips used on ISA bus cards is 719; chips used on PCI cards start at 720 and higher. Chips for PCI bus standalone adapters are marked YMF7x4, while on-board or embedded systems are marked YMF7x0. The DS-XG series features hardware-assisted XG MIDI synthesis with either 32- or 64-note polyphony, full-duplex playback and recording at any samplerate (internally upsampled to 48 kHz), external game controller and MIDI interface, and a legacy block for DOS application support. The DS-XG family processors were used in many inexpensive (sub-$50) soundcards. Relative performance was good despite the typical low cost. The cards were usually equipped with good quality 18-bit Digital-to-Analogue Converters, providing similar low noise and harmonic distortion levels to those found in semi-professional hardware. The XG synthesizer on the DS-XG series features not only basic XG System Level 1, but also some of the MU-50 additions, and can reproduce most musical data previously programmed for the popular DB50XG daughterboard. YMF7x4 cards shipped with a 2 MB bank of 8-bit samples by default, which must be loaded into system RAM during booting. Neither the resolution nor content of the sample bank are hardware limitations. A user can load their own banks using third-party tools to further improve sound quality or completely change the set of instruments. As with most other XG standard tone generators, YMF7x4 can switch itself into TG300B mode, which is an emulation of the Roland GS standard that allows adequate playback of musical data bearing the GS logo. Legacy support includes an OPL3 FM synthesizer, Sound Blaster Pro (22 kHz 8-bit Stereo) emulation and MPU-401 compatible MIDI interface. In addition to OPL3, DOS applications running under Windows 9x/Me can also use the XG tone generator. All of these features are available using Yamaha's VxD driver under