Help an old guy enter the 21st century

[Paul Ebert]

After I finish the DIY turntable I'm building for my son, I plan to design and build a set of speakers for myself. My current plan is to have them be open baffle below the tweeters. For me, this means going digital / active for the crossovers. My inputs are my DIY turntable and an old Sony DVD player with SPDIF and RCA analog outputs (only). I have a lot of LPs and CDs.

My research to date points me to one of three options:

1. A MiniDSP Flex to (probably) a NCore based set of amps
2. FusionAmps
3. Some sort of ADC / interface / pre-amp to a PC with CamillaDSP to a Topping DM7 to amps

My main question, at the moment, is if each of these approaches will provide the DSP horsepower I'll need to not only do 3-way digital crossovers, but also handle the EQ required for the open baffle midrange and woofers. The drivers are Bliesma T25B, Purifi PTT6.5X-04 and undecided for the woofers; currently leaning toward a bunch of Anarchy 708s in a slot loaded open baffle configuration. I'm pretty sure the 3rd option will, but it's also got the most risks given my rather antiquated knowledge of audio gear and it's also really stretching my budget.

 

[somebodyelse]

Any of them should have enough DSP horsepower. They've been used with various Linkwitz designs that probably have similar EQ and crossover requirements to yours. On option 3 consider something like the MOTU Ultralite Mk5 instead of the Topping - output performance and price aren't far off and it includes decent ADC and maybe toslink input.

 

[MAB]

I have a Flex Eight, using it in an active/DSP 2-way + subs now. I really like it. Also have an SHD for a pair of self-powered monitors and subs, also like that. I use the analog inputs on the SHD and phono preamp for turntable and other sources, that works great. You will have plenty of DSP power I think.

 

[Paul Ebert]

Any of them should have enough DSP horsepower. They've been used with various Linkwitz designs that probably have similar EQ and crossover requirements to yours. On option 3 consider something like the MOTU Ultralite Mk5 instead of the Topping - output performance and price aren't far off and it includes decent ADC and maybe toslink input.

So, if I went with the MOTU, I'd need a PC between its ADC and its DAC to handle the DSP? How would that work?

I have a Flex Eight, using it in an active/DSP 2-way + subs now. I really like it. Also have an SHD for a pair of self-powered monitors and subs, also like that. I use the analog inputs on the SHD and phono preamp for turntable and other sources, that works great. You will have plenty of DSP power I think.

Good to know. My thought for option 1 was to use a Flex. I expect that 4 channels will suffice.

 

[MAB]

So, if I went with the MOTU, I'd need a PC between its ADC and its DAC to handle the DSP? How would that work?

Good to know. My thought for option 1 was to use a Flex. I expect that 4 channels will suffice.

Yes. They have several configs. I think the 4 channel fits your purpose.

 

[somebodyelse]

So, if I went with the MOTU, I'd need a PC between its ADC and its DAC to handle the DSP? How would that work?

PC or some other computer like a Pi. Works the same as if you used the DM7 and some other interface as the input, except you wouldn't need the ASRC option in the CamillaDSP config as the ADC and DAC would share the same clock. I think @mdsimon2 has covered it in one of the CamillaDSP tutorial threads for the simple options. This one maybe? There's another turorial with toslink in and out which is conceptually similar. If you want/need something more complicated it can probably be done, often in more than 1 way, but that might not be a rabbit hole you want to go down.

Good to know. My thought for option 1 was to use a Flex. I expect that 4 channels will suffice.

Did I misunderstand? For stereo 3-way crossovers you need 6 channels. Plus another pair if you want headphones as an option.

 

[MAB]

PC or some other computer like a Pi. Works the same as if you used the DM7 and some other interface as the input, except you wouldn't need the ASRC option in the CamillaDSP config as the ADC and DAC would share the same clock. I think @mdsimon2 has covered it in one of the CamillaDSP tutorial threads for the simple options. This one maybe? There's another turorial with toslink in and out which is conceptually similar. If you want/need something more complicated it can probably be done, often in more than 1 way, but that might not be a rabbit hole you want to go down.

Did I misunderstand? For stereo 3-way crossovers you need 6 channels. Plus another pair if you want headphones as an option.

Yeah, maybe I am confused too. I thought two-way, but if you need 3-way stereo you need the Flex Eight or the new Flex HT I think. The problem with those is they don't have an analog input, which I was thinking you needed for the turntable, unless you have an A/D phono stage in mind. You can always get two Flex 4-channel boxes...

 

[DWPress]

A miniDSP 4x10 will do everything you need - ADC, digital input, DAC, 8 channels of XLR or RCA out to amp(s) and you don't need a PC in your chain after it is set up if you don't want to.

It's how I started out with my DIY active XO 3-way speakers +2 subs.

 

[Paul Ebert]

Oh, yeah... sorry for the confusion. I go back and forth between 3-way and using passive XO between the tweeter and the midrange and then digital XO between them and the woofers.

 

[Paul Ebert]

Another question. If I went with option 3 using some sort of mini PC (say, a MeLE Quieter 3C), what would I use to choose the input (turntable via ADC or CD player via toslink input; maybe in the future some sort of streaming or retrieval from a NAS) and set the volume? Is there some sort of interface from the PC to a universal remote or a smartphone app?

 

[Paul Ebert]

Anyone?