Pls help with modifying DSP crossover

[Hydrogen Alex]

Hey Guys,

I have bought a £400 DBX Driverack PA 2 and I think it is very good value. DriveRack PA2 | dbx Professional Audio

The DSP section for crossovers Eq and room correction is really superb.... But the A to D and 6 channel DAC's are not great. There is no digital input, only analog, so all sound sources are compromised both on input and output.

I am looking for someone with PCB trace cutting skills so I can access the digital input and digital output and allow me to use my own high end AKM A to D and 6 channel AKM DAC's.

Can anyone help me....?!
Thanks.
Alex.

 

[basreflex]

you assume identical I2S interfacing, and do you plan to reprogram the DSP as well ?
mostlikely the ADC range has been set to +20dBu max, and that eats away a lot from your noise floor.

 

[Hydrogen Alex]

I don't need to reprogram the DSP, just access the digital input and digital output.
Re the I2S level, I am assuming it uses the same levels as other DBX digital boards so matching levels should not be an issue.

The modified unit will be paired with pro sound balanced power amps and fed from prosound analog and digital sources so noise floor should not be an issue.

 

[rfbrw]

.....I am looking for someone with PCB trace cutting skills.....

I was unaware there was much skill involved. Cut section, lift and coat.

 

[Hydrogen Alex]

Sounds easy but.... I have destroyed a DEQX pcb ( expensive mistake!) trying to cut the traces so I dont want to make the same mistake again.

If I can find someone in England who can do this it would be fab.

 

[rfbrw]

Seems to me that you'll need more than just a cutter. Said candidate will need to know where to cut and how to add digital i/o in some form of enclosure. As an example, if you tap in after the onboard ADC output you will need to need to add an SPDIF receiver for the outboard ADC.

BTW, surely the DEQX pcb is repairable.

 

[Hydrogen Alex]

I can get access to the PCB schematic for the DBX and I am making a new larger case to accommodate the DBX pcb, A to D pcb and 6 channel DAC, this should make the location / connection for I2s input easier.

 

[esl 63]

Follow this with huge interest... hey lets face it, this is DIY Audio! We LOVE this!
Hydrogen Alex, you can make it!

 

[CharlieLaub]

I would abandon your fantasies about some quick mod of a DSP rack crossover box and move on to computer audio. Pair a computer with a pro-audio USB recording interface with 8 analog output channels and you will have something even better. Look for one with SPDIF input(s) if you would like digital input, or you can add a separate USB unit dedicated to digital IO like the miniDSP miniStreamer or USBstreamer. If the source is already coming from the computer, then there is no need for that. You mainly need good quality D-to-A sections. But even still the A-to-D side will be better than what you've got in the Driverack unit.

 

[gp4Jesus]

How about a mod to extend its bottom to 10hz?
*DRPA or DROA+ models

Mine are for home theater use.

thnx Tony

 

[CyberPit]

Hi Alex-San,
I recommend Just cutting the I2S line from ADC and inserting the TI SRC4392 between them. You can use the S/PDIF Digital Input and Original ADC Analog Inputs after modification. Some I2C control requires but it's not so difficult. A small PIC uP and the source selector switch are enough for your purpose.

 

[basreflex]

for the reasons of I2C control and programming, I prefer the SRC's from asahi kasei like the AK4127. that one is pin programmable, only needs a reset pulse.