HiFiBerry Amp+ vs DigiAMP+

[deef]

Topic pretty much sums it up, which one would you guys recommend for me to go with?

The price tag is somewhat lower on the HiFiBerry solution, so that's what I'm currently leaning towards, unless there's something I need to know, I'm open for suggestions.

Thanks.

[RaspberryQuiche]

I am on that quest too! My current amp is falling apart and I wan to replace it with an amp that fits on the Raspberry Pi. I use my Pi to play music and videos from internet and my NAS.

So I hesitate between the HiFiBerry Amp+ and the IQAudio DigiAmp+. But since I am new to this world of DIY HiFi, I have some questions!

1- My Pi is on all the time. I think that the DigiAmp+ has a mute option and the HiFiBerry doesn't. How much current would the Pi and the amp draw when muted? Same as not muted? I don't mind having a Pi drawing 2-3 watts all the time, but 35 watts is quite more.

2- I know I can use a physical volume control on the DigiAmp+, which is a very good reason for me to got this route. But I saw another post here saying that the guy has a volume knob on his HiFiBerry. So it IS possible on the HiFiBerry? If so, is it something I can think of doing (as a newbie)? Is it harder to achieve than on the DigiAmp+ ?

3- I know that in 2016, we can easily listen to radio on the internet, but I still want to use a hardware FM receiver. Can I do it with the Raspberry Pi and the HiFiBerry/DigiAmp+? Then can I use a physical knob to control the frequencies? How about a physical switch to toggle between FM radio / Raspberry Pi audio (music and videos)?

[PeteB]

This is pretty much what I am doing...

1: I have been monitoring the power on a Pi 2 with a HiFiBerry DAC+ using a small inline USB multimeter. It uses around 2 watts steady state, so 2W x 24 hr/day x 30 days/month, is about 1.4 KW-hr/month, or about $2/month (in the US). Muting the output makes little or no difference, most of that power is consumed by the Pi and the dongles, not the dac. So, it stays on most of the time.

2: I have been considering a hard-wired volume control using an encoder, which can be used with any dac. The problem is the software interface, not the dac hardware. This takes it out of range for newbies, unless you already know how to interface the encoder to a Pi. If IQAudio has included software to do this in one of the Distros they offer on their web site (there are several), I would say go for it. On the other hand, you could use a separate passive or active volume control on the output of the dac. The good ones are pricey, but the results are usually very good if you know how to use them.

3: Nothing is preventing using a radio Tuner in parallel with a Pi/DAC combo. Some tuners were integrated with a preamp, so they have inputs that can be used for any external source. You can connect the output of your dac to one of the several preamp inputs, and you are good to go. You can buy good used preamp/tuner combos on ebay, or complete receivers with plenty of extra inputs, for well under $100.

The dac becomes one of the sources you can switch using the front panel of the preamp. This is exactly how one of my two Pi's is hooked up, to a spare input on an old NAD receiver.

[RaspberryQuiche]

This is very interesting!

Your answer inspired me more questions

What amp are you using then? You only mentioned the HiFiBerry DAC+. And the measurement was done on the DAC+, but I imagine that hooking up the Amp+ would boost the power consumption dramatically?

The point of this project is to replace my old and very cheap amp that I don't want to spend time repairing. Is there any advantage of buying the amp and DAC separated?

I would like to add a fm tuner. Should I hook it up to the GPIO or use a usb dongle?
Then a knob controlling a rotary encoder for volume
Then why not a switch for toggling radio on and off (and bypassing kodi and mpd or other media app that I could use in the future)
Then why not leds showing the radio on / off state
Why not add a small LCD screen to display some information about volume
With all that power, it would be also nice to have a safe shutdown switch / power on!

I know for sure that it is a big project for my knowledge of electronics. But strictly talking about hardware, is this project even possible? Is there enough GPIO pins left? Some limitations that I should be aware of? Can the Raspberry Pi handle all this?

[PeteB]

The Pi can handle all that because in terms of computing power, the things you want are not as demanding as decoding audio or video files. It's possible, and people have done more complex projects (as a hobby, not to save money).

It would be a lot of work and additional expense. You are building a complete digital receiver, one piece at a time. It is cheaper and easier to separate the system into two parts. How you do that is just personal preference.

I did my measurements on the DAC+ and the DIGI+, adding an amp would increase the power. I leave the Pi w. DAC+ on, and I turn the receiver in the pic on and off as I need it. You can turn in on and off with the Pi, if you want. That way it only turns on when you play music.

The receiver in the pic must be 25 years old. It is an integrated AM/FM tuner, preamp, and power amplifier, in one case.

There is no big advantage in doing it my way. I just like older analog audio gear, and I prefer class A and A/B amplifiers over class D amplifiers, but all can produce very good sound. I usually do my audio projects on a small budget, and used 2-channel audio gear is cheap because most people want five or more channels.

[dunghnguyen]

@PeterB: Hi bro! It seems I found something out from you here since you were aware I am a newbie in one another thread in this Rune forum.

I intend to build Rune like a transport to play 2 channels audio controlled by smartphone so I am considering about the HiFiBerry DAC+. I wish to be shared from you:
- it has 3 ports out of coaxial / optical / USB ?
- it is 24 bit / 192kHz ?
- about its sound quality?
- the original HDMI output signal of Pi2 seems low, I tried it out to Yamaha receiver that I felt really low compare to Kodi case to play, hope it is better in case of HiFiBerry DAC+ ?

[PeteB]

[dunghnguyen]

Sorry to mix up above since I talked to DAC+ but asked also about coaxial / optical outputs of DIGI+ ... . I have 1 old MD player using as DA so it just decode 48kHz max so I intend to prefer DAC+ for my Pi2. For this I will have analogue signal to connect to amplifier Denon directly.

[PeteB]

This should work well for you with the Denon amp.

[RaspberryQuiche]

I am still confused about hooking up stuff to my Pi after plugging the solderless audio boards I mentioned in this post. How am I supposed to use the GPIO pins with this board sitting on top of the Pi? Should I use a GPIO expander?