Digital XO vs Op-amp XO, which would be best to use in active speakers?

[MikeHunt79]

I have a pair of bi-amped active studio monitor type speakers, and the amp PCB went wrong in one of them, the model is Event TR8.

Right now, i'm using a DCX2496 as a XO and have a seperate external amp for each speaker, but I plan to eventually put amps back into the speakers...

The speakers originally used an op-amp XO, 24db/oct LR @ 2.7KHz, and I was wondering which XO gives better sound, op-amp vs digital?

I understand the DCX2496 output stage is not the best, but if I was to upgrade this, would this give me better results than using an op-amp based XO?

[dangus]

I'd stick with the original op-amp crossover... there must be fewer active devices in the signal path than with the DCX2496. Maybe upgrade the opamps in the crossover, if they're something mediocre.

[AndrewT]

I have tried and for the time being rejected opamp based active crossovers.
They are too noisy. I tried optimising the components around the opamps to reduce the noise but was only partially successful. I used opa275

[richie00boy]

Did you use those boards that Jens designed Andrew? I have my own designs and have never had any problems.

[MikeHunt79]

Originally Posted by dangus

I'd stick with the original op-amp crossover... there must be fewer active devices in the signal path than with the DCX2496. Maybe upgrade the opamps in the crossover, if they're something mediocre.

Easier said than done, the op-amp's appear to be the SMD type on the original PCB... I only have the skills to do thru hole stuff. The original PCB's have now been removed from the speakers also, in my opinion it would be easier to make a new PCB with just a XO circuit, as the original PCB has both a XO and AMP section on a single PCB.

Originally Posted by AndrewT

I have tried and for the time being rejected opamp based active crossovers.
They are too noisy. I tried optimising the components around the opamps to reduce the noise but was only partially successful. I used opa275

Well, I'm normally sat within a few feet of these speakers, so I would like then to be as quiet as possible. Admittedly, the stock DCX2496 uses an op-amp based output stage, but I think installing line level audio transformers which is said to give notable improvements.

I also quite like the versatility of the digital XO, being able to fine tune XO slopes and XO points in real time is great, so I think I'm going to go the digital route.

[andyr]

Originally Posted by AndrewT

I have tried and for the time being rejected opamp-based active crossovers.
They are too noisy.

Hi Andrew,

I use Rod Elliott's op-amp based analogue XOs for my 3-way Maggies (tweaked slightly to use a 3rd order bass LP slope) but I would be very interested in constructing a discrete equivalent.

If you have rejected opamp-based active XOs, may I ask where you got the schematic for a discrete analogue XO?

Regards,

Andy

[reins]

Hi,

I build similar dipole speakers with both systems. Personally I use an analog XO, because I have a turntable and therefore don't want an digital stage in the system.

For a friend of mine I build a similar system based on the DCX (jannemann upgrade) because he uses only digital sources. I think this is the way to go for systems without analog sources. It is much more flexible and easier to change/play with.

Regards
Stephan

[richie00boy]

andyr, I don't think Andrew made a discrete xo, he was saying to try digital.

[andyr]

Originally Posted by richie00boy

andyr, I don't think Andrew made a discrete xo, he was saying to try digital.

But surely, Richieboy, digital XOs use opamps?

(He said opamp-based XOs had too much noise.)

Regards,

Andy

[richie00boy]

A digital xo does the processing digitally, it's not op-amp based.