The delay circuit is shown uses the Mitsubishi M65830 Digital delay chip. This has been about for a while now, and is simple and able (provided that a anchored adjournment is acceptable). The consecutive abstracts appropriate to access altered adjournment settings is not calmly obtained, and would add appreciably to the complication of the circuit. As such, it would no best be a simple amount to assemble application Veroboard or similar, and would crave a printed ambit board.
The circuit is (almost) a absolute adjustment from the Mitsubishi data sheet, and as shown will give good performance over a wide frequency range. The filters are acquainted to about 9.5 kHz, and although this could be bargain there does not assume to be any acceptable acumen to do so. This seems to be the optimum acknowledgment for rear approach speakers, so should be larboard alone. The clarify circuits use centralized opamps, and only require the external components shown below.
As shown, the assemblage can be complete as a bore absolutely easily, acute a 5 Volt supply, alternation and agenda apple connections, and an ascribe and output. This is accessible to wire up, and will accumulate (expensive) mistakes to a minimum. The two 68nF capacitors should be akin to aural 5% for best results, according to the Mitsubishi abstracts sheet, as these ascendancy the accentuation (analogue to agenda conversion) and demodulation (digital to alternation conversion). Standard altruism capacitors are accomplished for the others, and as accepted I acclaim 1% metal blur resistors. The 2MHz clear (or you can use a bowl resonator if you prefer) is apparently the alone account (apart from the M65830) that may be a little awkward to obtain, The 5 Volt supply must be regulated, as anything over 6 Volts will destroy the delay chip. See Figure 4 for a suitable power supply circuit.
Schematics for Surround Sound Digital Delay Unit using M65830 Circuit Electronics