Preamp quandary for 2.1 or 2.2 stereo

[ad_fletch]

Ah gotcha.

Yeah for under $500 I think it comes down to MiniDSP or messing with CLIs. I’m not averse to opening Powershell to get things done in Windows from time to time, but i haven’t messed with Linux since high school, unless you count rooting Android etc. Maybe I should have done Comp Science instead of law!

CamillaDSP, BruteFIR, Ecasound, TI Puepath et al do sound great, but I need to decide whether my tired old brain can handle the load (one thought that occurs to me is I might blow things up with my software experimentation, esp if there’s no real volume knob in the chain)….

 

[rwortman]

I am currently listening to my Emotiva PT100 preamp/dac driving my Crown XLS 1502 amplifier which is connected to my PSB Imagine T2 speakers. Sublime. I have a Yamaha Aventage AVR. I don’t switch the speakers, I run the L/R pre outs from the AVR and the PT100 into a line level A/B switch so the amp drives my front speakers in surround or two channel mode. The preamp sold for $300 US and I got the amp on sale for the same price. Emotiva has a new model preamp now that is $100 more expensive. Major difference is that it now includes a Bluetooth input.

 

[ad_fletch]

PT100 is another intriguing option thanks.

Seems it only has full range sub out though (no crossover). Also only stockist in this benighted southern land wants nearly US$600 for one! Great feature set for a pre though.

 

[rwortman]

Most subs have their own crossover making the preamp crossover unnecessary and a switch on the back for LFE mode that bypasses it for AVR use. My SVS sub has bluetooth control so I can set it use the crossover for two channel listening or none when running from the AVR.

 

[ad_fletch]

As per my first post, my subs only have controls on the back, so not as convenient as yours.

Anyway, I took some brave pills and ordered the Allo Piano 2.1 to use with a Raspberry Pi. Allo’s other products seem well designed (see eg Amir’s Allo Boss2 review), so fingers crossed.

Total (incl nCore amp, Raspberry Pi, case, dac, speaker switcher and couple of new Monoprice cables) will be under AU$1000, so I guess I’ll find out whether it’s possible to achieve my 2.1 dream within that budget…fingers crossed!

 

[rwortman]

Where, then, is the volume control. Software?

 

[ad_fletch]

Initially, I am planning to insert my JDS Atom into the chain to control volume. Once I get comfortable with moOde, I might connect the Piano DAC directly to the Hypex.

 

[Shanman]

Here's something for the 2.1 folks that I had not realized came available last month.

Emotiva PT1

 

[ad_fletch]

Thanks.

I think that's the new model to which @rwortman referred earlier in this thread. Emotiva themselves compare it with his PT100 like this:

The new BasX PT1 builds on the legacy of our ground breaking PT-100 preamp/tuner/DAC to bring you the next step in the evolution of affordable audiophile components. The PT1 features upgraded electronics, a streamlined menu system that allows you to tune and program FM stations directly from the remote control, and a sleeker more modern design aesthetic.

 

[ldarieut]

I have turned around the same problem for over a year and eventually I bought a minidsp shd. I didn’t need a dac and a streamer but there really was no other alternatives that I found with digital crossover, analog in/out and good performance.

 

[Epos7]

I have turned around the same problem for over a year and eventually I bought a minidsp shd. I didn’t need a dac and a streamer but there really was no other alternatives that I found with digital crossover, analog in/out and good performance.

I'm curious about the SHD. Can you share how you have things set up with it?

 

[ldarieut]

I'm curious about the SHD. Can you share how you have things set up with it?

Sure: minidsp shd has squeezelite plugin for the onboard volumio, this allows me to connect the minidsp shd to my network of squeezebox and Logitech media server for digital streaming.
The minidsp shd feeds two hypex ncore nc400 monoblock with balanced cables and then they go to some old triangle speakers.
I also have a DJ art pre2 for my turntable which is plugged in the rca analog in of the shd.
for the moment I am not using the crossover, but i have diy speakers in mind for the near future.

 

[Epos7]

Sure: minidsp shd has squeezelite plugin for the onboard volumio, this allows me to connect the minidsp shd to my network of squeezebox and Logitech media server for digital streaming.
The minidsp shd feeds two hypex ncore nc400 monoblock with balanced cables and then they go to some old triangle speakers.
I also have a DJ art pre2 for my turntable which is plugged in the rca analog in of the shd.
for the moment I am not using the crossover, but i have diy speakers in mind for the near future.

Thanks. The SHD is an intriguing option that may work better than the Topping Pre90 for my needs.

 

[ad_fletch]

I have turned around the same problem for over a year and eventually I bought a minidsp shd. I didn’t need a dac and a streamer but there really was no other alternatives that I found with digital crossover, analog in/out and good performance.

I agree the SHD looks like the best solution. I might get one at some stage. I am keen to see how close I can get to its performance with around US$100 worth of Raspberry Pi-based kit though.

For reference, this is the 4 channel DAC I've ordered, which can do crossovers via DSP built into the DAC chips:

 

[ad_fletch]

I notice @johan that you design Allo's DACs - did you design this one by any chance? Just wondering if you have any measurements to share (in the spirit of ASR) over and above the specs listed on the website:

• DAC SNR is 112dB
• DAC THD+N @ - 1dBFS are –93dB
• Full Scale Output of DAC is 2.1Vrms
• Dynamic Range of DAC is 112dB
• Sampling Frequency ranges from 8 kHz to 384 kHz. (Sample rate is limited to 192kHz, for subwoofer modes - 2.1 & 2.2)
• Ultra-low-noise voltage regulators for optimal audio performance

Having ordered one already, I'm obviously not worried, just curious really.

 

[johan]

Hi

the specs are the same as for our Boss(version 1.2)

 

[ad_fletch]

Ok thanks.

So according to ASR measurements, it's similar to JDS Element and a step up from the MiniDSP 2x4HD in terms of SINAD. Even better at moderate output levels (my new amp supposedly achieves max power with 1.66v input, so I'm guessing I'll mostly be in the sweet spot). Nice jitter performance too.

Not as good as Katana/Boss2, but those aren't multichannel, so not a fair comparison.

Can't wait to receive it (delivery to Aus could take a while).

 

[Epos7]

So according to ASR measurements, it's similar to JDS Element and a step up from the MiniDSP 2x4HD in terms of SINAD.

Interested to hear your results. I'll likely get a miniDSP 2x4 HD to handle to provide DSP to my two subs. The Allo/RBPi combo sounds like it may be another good option.

 

[mdsimon2]

Ok thanks.

So according to ASR measurements, it's similar to JDS Element and a step up from the MiniDSP 2x4HD in terms of SINAD. Even better at moderate output levels (my new amp supposedly achieves max power with 1.66v input, so I'm guessing I'll mostly be in the sweet spot). Nice jitter performance too.

Not as good as Katana/Boss2, but those aren't multichannel, so not a fair comparison.

Can't wait to receive it (delivery to Aus could take a while).

How so? Looks to me to be completely identical to the 2X4HD in terms of SINAD (~96 dB). If you want a step up from the 2X4HD your best bet is probably a RPi + MOTU M4 (using software DSP).

Michael

 

[ad_fletch]

There's no dashboard, but at some stage during the 2x4HD thread, Amir estimates 90 for the HD's SINAD. Not a big step up I'll admit, but my experience to date is that 90ish with poor jitter rejection (eg Chromecast Audio) is around the point where I start to hear issues with the few DACs I've had.

Fooling myself? Could well be, but my guess is the Piano will be good enough. We'll see.

EDIT: Motu M4 looks great by the way, but in Australia, RPi+ Piano 2.1 is around $150 and the Motu is around $400. I'm sure it's well worth the extra, but I couldn't find one in stock anywhere anyway.