1st Order (6dB per Octave) Crossover!

[heeman]

The miniDSP is a digital device, so it makes sense to supply it with a digital input. While the miniDSP has an analog input, using this means that the signal is run through an A/D and D/A conversion before sending to the power amplifiers. For me, this is an unnecessary conversion step which I would like to avoid in my mainly analog system. Playing from my computer using digital files or streaming would be fine to send digitally to the miniDSP, but playing vinyl would have to go through a digital step. I just don't like to do that because there are losses, however small.

Thanks! So what active x-over do you use?

 

[MakeMineVinyl]

Thanks! So what active x-over do you use?

I design and build my own. Pauly has one of my previous designs in his system.

 

[MakeMineVinyl]

I was working with the voicing filter I use for the HF horn this morning. This filter comes after the active crossover. This is the equalization curve which should be used for the HF - this is close to the curve provided by the original Altec passive crossovers (curves for this crossover shown below) for the Voice of the Theater. This curve shelves down the efficiency hump of the compression driver below around 4kHz - if building a new passive crossover, make sure to duplicate this curve into the design. Without it there will be an excess of energy from the crossover point up to that frequency.




Altec N500G Passive Crossover Curves

 

[malsackj]

MakeMineVinyl how do you feel about the use of something like the DBX Driverack. yes it is still AD and DA.​

 

[MakeMineVinyl]

MakeMineVinyl how do you feel about the use of something like the DBX Driverack. yes it is still AD and DA.​

I don't know what the DBX does. As I wrote originally, in my predominately analog system an additional A/D - D/A conversion doesn't make sense (except for the subwoofers which is where the miniDSP ended up). Weighing what DSP can do verses any possible degradation and potential clipping issues (my system has all its voltage gain in the preamp with the power amps almost unity gain), any meaningful filtering/EQ I need can be designed and built easily. This very likely isn't an issue in other systems where DSP is more practical and the sonic impact is likely to be less of an issue. Also, someone who only has digital sources can obviously plug the output of their computer directly into something like the miniDSP and there is little to no degredation.