[wgscott]

I just bought this for use with my Apple TV in the garage (since I already have some ... err... Bose bookshelf passive speakers).

https://www.parts-express.com/smsl-q5-2x50w-amplifier-dac-with-optical-coaxial-usb--230-208#lblProductDetails

I'm using this with a projector hooked up to the HDMI out from the Apple TV, and am using the ATV optical out to the little amp.

It sounds great, even when cranked way up.

It is a lot smaller than I thought it would be:





It lifts veils, opens up the soundstage, punches above its price point blah blah blah.

The sound is reasonable, but it is by no means true hifi.  There are tone controls accessible via remote or by clicking on the volume knob.  The setting ranges from 0 to 13 for treble and bass.  There is no indication where neutral should be, but I am guessing around 7.  If you turn them all the way down to 0, it sounds bad.  It is barely larger than the AppleTV I have paired it with.  For my application it is fine.  Similarly, for a pair of outdoor speakers, or some other low-fi application, this is a good deal.   

I would give it a B+.[/QUOTE]

[JohnR]

Wow. Nice find.... a hundred bucks for literally everything (except speakers)! There's been a few times I could have recommended something like that.

[OzarkTom]

Shucks, out of stock. The remote is worth a hundred bucks.

[srb]

I just bought this for use with my Apple TV in the garage (since I already have some ... err... Bose bookshelf passive speakers).

I have two questions for you:

1.  From user scoobnz on the PE site: "A few quirks about it, the volume always resets to 16 when powered off and on, and for sensitive speakers this can be quite loud when starting up. The other is the volume scaling is somewhat strange, 1-10 are almost the same then a large jump at 11 then again at 16.. not sure why but it makes precise volume setting a little difficult."

Did you find the same volume jump anomalies?

2.  Does the input reset to a default input when powered up or does it remember the last input selected?

Steve

[MLS]

wgscott,  Any chance to get a shot of whats under the hood?

Thanks,

Scott

[wgscott]

I have two questions for you:

1.  From user scoobnz on the PE site: "A few quirks about it, the volume always resets to 16 when powered off and on, and for sensitive speakers this can be quite loud when starting up. The other is the volume scaling is somewhat strange, 1-10 are almost the same then a large jump at 11 then again at 16.. not sure why but it makes precise volume setting a little difficult."

Did you find the same volume jump anomalies?

The volume does reset to 16, which isn't problematic with my 18 year old inefficient Bose 301 bookshelf speakers.  I haven't noticed any discontinuity with the volume. (I've only turned it up, not down, from 16).

2.  Does the input reset to a default input when powered up or does it remember the last input selected?

It seems to change almost randomly.  I suspect it might coincidently share an IR code for some function on my AppleTV.  (Edit:  The down arrow button for the Apple TV remote also toggles the input for the dac. The ATV lets you re-program the remote, but I find it easier just to set the thing back to optical manually (I use the otherwise useless channel up/down on my harmony remote).

 

[wgscott]

wgscott,  Any chance to get a shot of whats under the hood?

Thanks,

Scott

I'll see if it comes apart readily...

[wushuliu]

wgscott,  Any chance to get a shot of whats under the hood?

Thanks,

Scott

goes without saying it would probably sound a notch better with all the questionable quality caps, posts, and output signal wiring replaced. Nice find though.

[wushuliu]

Description
Q5 pass CE, FCC, RoHS certification, compliance with EU WEEE directive.

Q5 pure digital amplification technology, high-quality amplifier, to support the current mainstream of the world, including audio mode optical fiber, coaxial, computer USB, analog input. For computers, LCD televisions, set-top boxes, digital boxes, Blu-ray and HD-DVD and other equipment to use, rich input mode there is always a way to fit your audio input device. Each channel output 50W (2 channels), most of the crowd listening to meet the requirements.

Q5 using ST's high-quality digital amplifier series - digital power amplifier STA350BW, designed for digital modulation technology products designed chip. Any kind of PWM modulation scheme (such as the three value increment, phase shift or binary delta modulation technique) perfect support other brands. ST using the most advanced BiCMOS-DMOS process technology, this new amplifier chip, the technology allows the same chip integrated DMOS power stage, bipolar transistors and CMOS structures.

Q5 uses FFX technology, features FFX series is a high quality, low power consumption, green.

Q5 uses the 'Easy Start' patented technology allows precise control of the power supply circuit order to make this technology to improve the sound system reliability.

Q5 to meet high-definition Blu-ray and HD-DVD format for demanding audio interface standard sampling rate 44.1-192K own testing.

[wushuliu]

got this from diyaudio re: the STA350BW chip. Not bad distortion:

[wgscott]

goes without saying it would probably sound a notch better with all the questionable quality caps, posts, and output signal wiring replaced. Nice find though.

Thanks for posting this. Despite this thing sitting on my tool bench in the garage, I haven't got around to dissecting it.  I must be getting old.

[JohanH]

Not sure if I should post this here but here's another one based on the same chip. No remote and USB though and a bit more expensive

http://www.muc89.com/components/hifi-amplifier/amper502-highres-full-digital-sound-terminal-50w-50w.html

[srb]

Not sure if I should post this here but here's another one based on the same chip. No remote and USB though and a bit more expensive
http://www.muc89.com/components/hifi-amplifier/amper502-highres-full-digital-sound-terminal-50w-50w.html

Some other differences:

The Amper502 does not come with a power supply.  It can operate as a low-power amplifier from a 5V/500mA USB port (DC to USB-A cable included), otherwise you will need to furnish a 5V - 20Vmax DC supply.

As the STA350BW is a true digital amplifier (or "power DAC"), there is no external D/A converter.  The SMSL Q5 uses the AKM AK4113VF input receiver while the Amper502 uses the Wolfson WM8805 transceiver which on paper should give it an S/PDIF performance advantage.

The Amper502 has no analog input while the SMSL Q5 has an analog input via an AKM 5358A A/D converter.

The Amper502 has a spiffy OLED display.

I haven't yet found any North American vendors for the Amper502.

Steve

[hanspp]

Meanwhile an additional smaller amplifier with STA369BW in -S version with  2 x 20W is offered here:

http://www.muc89.com/catalog/product/view/id/198/?___store=muc89_en

May be this -S Version could sound quite good even from a 5V USB port  when commonly used?

I guess the 76 Euros include german VAT, so when shipping to US this should equal to approx $73 + ship?

[wgscott]

I've been having some trouble with my unit spontaneously shutting the power off while playing music.  It is really quite frustrating and has made me re-consider recommending this thing.  Hopefully mine is just a lemon.

[hanspp]

... then may be the little more expensive AMPER502 from muc89 is worth the small premium - it seems not only to have a premium S/PDIF transciever, but also a more robust 32bit ARM µC..

And since Dollar-Euro parity is only a matter of time...

[MLS]

I just got one of these.  I have only listened for a little bit with some of my DIY speakers but I am pleasantly surprised with how it sounds and how flexible it is.  The remote is nice to have but weak at best.  I am looking forward to swapping some more speakers with this little all in one amp.

Scott

[cujobob]

I've been having some trouble with my unit spontaneously shutting the power off while playing music.  It is really quite frustrating and has made me re-consider recommending this thing.  Hopefully mine is just a lemon.

I hope you contacted the vendor to have the newest version sent to you. Apparently version one was quite buggy. I just ordered myself the newest version from PE, but considered the AMPER model too... Unfortunately the 502 is not stocked currently.

Seems like a really nice idea if one can get a reliable unit. I've needed something for TV setups since my most recent TV purchases do not have RCA outputs.