Has the Topping A50 headphone amp appeared yet?

[saturnaal]

Was pleasantly surprised today to find the Topping A50 had arrived two days early of its estimated delivery date.

Predictably enough, comes in a box very much like the one the D50s comes in. Includes the A50, the power adapter, warranty card, and manual which includes factory measurements.

Build quality is effectively identical to the D50s, as expected. I love the size and form factor of these devices. The desk footprint to performance ratio is great compared to many things in the bracket. Volume knob feels great, though I think I would have preferred either a grooved knob or a slightly longer one for my clumsy fingers.

Coincidentally, the D50/D50s/A50 stack perfectly with the Koss E/90 Energizer if you're so inclined. I didn't take a pic of this, but it looks pretty slick. Too tall in my case.

Snapped a couple of quick pictures:

Spoiler: Expand Photos

All hooked up now and working like a charm. Listening with my somewhat modified Fostex T50RP MkIII, it does what it says on the box. Very clean, no audible distortion, and plenty of power even for these somewhat difficult to drive planars. I'm using the 3.5mm port, rather than the 2.5mm "balanced" port which provides substantially more power, so I imagine the A50 can drive nearly anything. On some recordings I'll get the volume up to ~3-4 o'clock and I consider switching to high gain, but realistically low gain takes the volume up as high as I'll ever listen (definitely louder than I should).

When the amp is on, the outputs are disabled. Turn it off again, the input immediately passes to the outputs (a Koss ESP950 in this case). I had thought I'd be disappointed in the lack of "pre-amp" capability, but I've come to prefer controlling the volume with the D50s using the remote control. Works great, as I can roughly level match for both devices and not get any surprises in volume when switching between the two.

Using Tin T2 Pro IEMs there is no detectable hiss at max volume as expected.

Gets moderately, but not alarmingly warm.

Natural habitat:

Spoiler: Expand Photos

All in all, would recommend. I suspect independent measurements will confirm factory specifications. Topping has been consistent in this and very transparent with public measurements. Seems to be catching on. The A50 makes a fine addition to the options available at this level of performance. Great look and feel, and 'aesthetic' stacking with the D50/D50s. And as luck would have it, also the Koss E/90 and JDS Switcher / O2. Will you be able to tell a difference from your O2, Atom, Magni, or similar? Probably not.

But, I like it.

 

[Zerviscos]

Using Tin T2 Pro IEMs there is no detectable hiss at max volume as expected.

Oh that's quite good to hear. Now I'm kinda interested on this.

 

[sweetchaos]

Topping updated their site to include A50:
http://www.tpdz.net/products_detail/productId=45.html

 

[Scriba]

Is already a device on the way to @amirm?

 

[ninetylol]

I wonder how this compares to the Heresy and SP200. Especially considering the digital volume control on the A50. Im happy with the SP200 but this whole changed potentiometer in retail versions and the fact, that my unit doesnt change the volume from 1 to 6 a clock in low gain makes me want to get something else.

Anybody can shed some light on how to read the official Topping A50 measurements vs the Heresy and SP200?

 

[JohnYang1997]

I wonder how this compares to the Heresy and SP200. Especially considering the digital volume control on the A50. Im happy with the SP200 but this whole changed potentiometer in retail versions and the fact, that my unit doesnt change the volume from 1 to 6 a clock in low gain makes me want to get something else.

Anybody can shed some light on how to read the official Topping A50 measurements vs the Heresy and SP200?

Care about lowest distortion, low output impedance = sp200
Care about channel balance = a50

 

[L5730]

All this trouble with the naff implementation of a stereo log pot for volume, there has to be something better.
A couple of switches and a choice of gain levels, then just control it in the DAC/software?
Or put a volume pot in the thing, but do it differently. The pot would control a circuit which in turn would then control the actual signal gain - can't be that much more expensive or noisy? This is what has been done in the A50 - uses a chip.

 

[JohnYang1997]

All this trouble with the naff implementation of a stereo log pot for volume, there has to be something better.
A couple of switches and a choice of gain levels, then just control it in the DAC/software?
Or put a volume pot in the thing, but do it differently. The pot would control a circuit which in turn would then control the actual signal gain - can't be that much more expensive or noisy? This is what has been done in the A50 - uses a chip.

If you actually think through about part counts you will understand that this method is actually cheapest and simplest. One good relay alone is probably more expensive than the IC. Let alone a couple of. Controlling the switches need microcontroller and that is a lot of pcb area and components, which is well used in DACs like adi2dac and element x.
Putting a pot in the feedback does not do anything beneficial. 1 it requires inverting amplifier which in itself is more noisy configuration than non inverting. 2 the channel imbalance is the same as traditional method 3 putting pot in feedback path can potentially increase distortion as well.
Are there better ways? Sure use better pot or use parallel connection and adding an attenuation setting.

 

[L5730]

dual gang pot = cheap and easy implementation, but requires a lot more labour intensive quality control, else expect to keep getting products back and negative reviews. It seems JDS Labs have openly addressed this exact issue, but I'd have to see their efforts to fix to believe it.
That said, if folks don't measure channel imbalance, how much will it need to be for them to actually detect as an issue? I think anything more than 0.25 dB has been mentioned.

Apologies if I am coming across as an @55.

 

[ninetylol]

Just waiting for some measurements so i can pull the trigger on this!

 

[noel_fs]

doesnt seem like a good value

 

[ninetylol]

Still wondering why its nowhere available but long term shipping from China.

 

[saturnaal]

Shipping from Hong Kong to the US was really quick, I'm not sure there's a need to stock it domestically unless the demand is really high enough.

 

[mid_fi_Senpai]

Just ordered mine last night. I too am wondering why there are no reviews for this thing online.

 

[mid_fi_Senpai]

A50 came in today. Nice looking piece of tech. I'm no "Tech Wizard" but I was able to measure the output with a DVOM. Measured 3.9 ohms on right channel and 4.4 ohms on the left. That's about as far as I can go with the tools I got. Only able to test the 6.3mm and 3.5mm jacks. I dont have any 2.5mm balanced cables.

Sounds good even with a set of 16 ohm Tin T2's. I'm sure internally thats not a good match, but again, I don't have the tools to measure what its really doing. Highest impedance headphone I have is the Fostex T60rp. They sound different from my next highest impedance headphone the Tin T4. But that could just be because I'm comparing apples to oranges. I notice a slight difference on tracks that I'm used to but that could just be placebo. Either way. Happy with my purchase.

 

[Unappreciated]

A50 came in today. Nice looking piece of tech. I'm no "Tech Wizard" but I was able to measure the output with a DVOM. Measured 3.9 ohms on right channel and 4.4 ohms on the left. That's about as far as I can go with the tools I got. Only able to test the 6.3mm and 3.5mm jacks. I dont have any 4.4mm balanced cables.

Sounds good even with a set of 16 ohm Tin T2's. I'm sure internally thats not a good match, but again, I don't have the tools to measure what its really doing. Highest impedance headphone I have is the Fostex T60rp. They sound different from my next highest impedance headphone the Tin T4. But that could just be because I'm comparing apples to oranges. I notice a slight difference on tracks that I'm used to but that could just be placebo. Either way. Happy with my purchase.

View attachment 43248

I thought balanced is 2.5mm.

 

[Veri]

I thought balanced is 2.5mm.

Yep DX7 Pro had 4.4mm balanced A50 has 2.5mm balanced

 

[renoxd]

Sorry for silly question but i have ordered topping d10 few days ago and now I'm looking for an amp for my future HD 650 headphones.
I also have active Edifier r2730db speakers that i would like to plug into amp (as d10 has only one output)
Would A50 be a good amp for such a setup? Or maybe Atom amp or Liquid Spark are still better way to go.
Music i like: Electronic, Trance, Soundtracks, Vocals, Piano,

 

[L5730]

Sorry for silly question but i have ordered topping d10 few days ago and now I'm looking for an amp for my future HD 650 headphones.
I also have active Edifier r2730db speakers that i would like to plug into amp (as d10 has only one output)
Would A50 be a good amp for such a setup? Or maybe Atom amp or Liquid Spark are still better way to go.
Music i like: Electronic, Trance, Soundtracks, Vocals, Piano,

Happy Holidays!
With those speakers, they have a digital input and internal DAC so you could run the D10 DAC directly to them with a digital link but this would be for PCM audio at sample rates and bit depths that the speakers own internal DAC can handle (read their manual for specs).
For DSD and any PCM that the speaker's own DAC don't handle, you'd have to use an analogue connection from the D10 DAC.
The good thing about the Topping A50 headphone amplifier compared to others mentioned, is that you could plug the RCAs from the D10 to the A50 and leave the RCA connections from the A50 to the speakers. When the headphones are plugged in the RCA outputs to the speakers are muted, and when the headphones are unplugged it's a straight pass through*. All of the other products put the analogue volume pot in the signal path, which is good in one way as you then have a stereo master volume control for your speakers, but is a pain if you don't need it and don't want to turn the headphone amp on.
You'd have to buy a switcher box with the other products if you did not want the headphone amp turned on and it's volume pot in the signal path when using the speakers.

* I don't know if it's a perfectly true pass through with measured negligible impact (maybe a tiny addition of noise?), but all indication is that it is just that.

 

[renoxd]

Happy Holidays!
You'd have to buy a switcher box with the other products if you did not want the headphone amp turned on and it's volume pot in the signal path when using the speakers....

Happy holidays to you and to everyone in this forum!

I don't understand why I should buy. Couldn't i just plug out headphones from port and have the same result?

I also don't understand why volume knob working (amp itself), when have the speakers on is a bad thing.
I could use it to increase the volume for speakers. Of course i understand that i have to be caerfull to not damage them.