[soumya.banerjee]

My guess is it should be 200 milli Ohms instead of just Ohms. Given how nicely biased this amp is with my IE 800 (single ended low gain) and Noble Audio Kaiser Encore (using 4 pin XLR to 4 pin 2.5 mm jack) and how dynamic it sounds, the impedance CAN NOT be more than an ohm.

 

[gulakpii]

I used the H20 with my 32 ohm and 300 ohm headphones and it sounds fantastic, and I never notice the output impedance of XLR amp is 200 ohms.
I just checked their Taobao website, and their spec says "the pre-amp XLR (in the rear panel) output is 200 ohm.
Would this have been a translation error, such that the pre-amp XLR is 200 ohm and NOT the "front XLR" phone jack?
Just guessing!

 

[mandrake50]

I agree. They (Gustard) , for their own good, should really get this fixed.
Many do not have the advantage of an astute group of users such and on this forum.
Who knows how many have not bought the amp based on the published specifications.
Every place that I looked Everywhere the specs are published based on many, many Google searches)
This specification result is posted.

 

[davveswe]

I asked shenzeaudio, and they replied with this.

Hi!

Is it really 200ohm. Like it says on product details?

Front analog output (XLR):

Output impedance 200Ω


Their answer is:
Dear David,Front analog output (XLR):Output impedance＜0.1Ω.
200Ω is rear xlr output impedance.

 

[wwmhf]

Thanks folks!
Coincidentally that's the exact phrase I used to break the good new to my friends in local circle - "unboxing new toys".

I am still waiting on Amazon to deliver the XLR cables. There after I will test with K712 Pro and HD 800.
Thus far, I have tried with EL-8 Open, Shure SRH840, MDR 7506 and M50x.

It took me barely 20 minutes of listen yesterday, and I knew I am not going back to my Schiits - Lyr 2 (Gold Lion tubes/LISST or Valhalla 2).
And I have listened to several other amps at events and my friends place including Audeze Deckard, RJM Sapphire, some WooAudio crap (can't recall which one), Burson Play (with several OPAMPs at different stages), Aune B1 and Aune X7.
None come close to this amp's clarity, pace, tonality and immensely accurate biasing of load.

My gripes thus far are:
1. For silver model, the markings are in white - which is very difficult to read. Black variant is fine.
2. The matrix based pot triggers relays to switch for every change in volume. Can be annoying to someone else present who is not wearing a headphone.
3. There is no manual whatsoever. Just a warranty card from Gustard.

My unit was manufactured on Jan 24th 2018, just couple of days before I placed order at Shenzhen Audio.
The amp tends to use some kind of adaptive biasing current/voltage, based on load it seems - very similar to Lyr 2.
It has two 6.3 mm SE jacks - one for low impedance loads and another for high gain impedance loads.
There are a total of 4 x 3300uF Nichikon caps. 2 per channel. Separate power supplies as you can see from snaps each having their own toroidal copper transformers.
Heat sinks have been used very generously for current stages, which though get hot, it never dissipates down to outer aluminium chassis much. It remains just mildly warm even after several hours of usage - may be because it's winter here. Still using Schiit Lyr 2 with tubes / Valhalla 2, I could fry eggs after about 90 mins of operation.
Chassis has pretty thick aluminium sheets / slabs and is very sturdy and well built.
There is no vibration whatsoever either from transformer or any other components under operation.

The gain switch is very special - it's not the typical gain switch in other desktop amps where flicking it results in sudden spike/drop in amplitude.
Instead its soft and subtle and takes about couple of seconds to make the load over-driven / under-driven or just correctly biased. Very neat implementation.
Thus far I have not played around with OPAMPs at all. So everything is using LME49720 - two of them socketed as you should find in one of the snaps.

Together with Spring, the chain sounds unbelievably transparent, resolving. Every transient hits the transducer with such force.
Just to make sure I have individual impressions of the DAC and AMP, I initially chained H20 with my previous DAC - SMSL M8A powered by a Sony 5000mAH power bank (since the DAC sounded cleanest that way). Both using PCM with linear phase slow roll-off and DSD 512 upsampled using Foobar DSD Processor - Type C and some DSD256 upsampled from FLACs using SoX. I immediately felt the urge to crank up the volume since I was enjoying the dynamics and pace of the amp. I usually don't listen very loud and exhibit extreme restrain by setting optimal loudness level by listening to 1kHz sine wave test tone at 0dBFS for a while. But yesterday, I threw all that out of window
And things went uphill after Holo Spring came in the picture.

I shall update my impressions with HD 800 / K712 Pro /EL-8 once XLR cables show up. That'll be 5V RMS per channel into H20.

Here some snaps which I took yesterday, please ignore my shoddy skills behind the lens.

Thanks a lot for sharing your experiences with us. Looking forward to your updates.

 

[Alcophone]

Drop is live again ($799), just for a few days, though. I like that the output impedance issue is dealt with, now what worries me is the lack of warranty.

 

[sahmen]

Yes, the lack of warranty really blows. For me, it is a deal-breaker, but then again, I already have the Violectric V281, so my interest in this unit came from a certain curiosity, and not from real need.

 

[Zennheiser]

Yes, the lack of warranty really blows. For me, it is a deal-breaker, but then again, I already have the Violectric V281, so my interest in this unit came from a certain curiosity, and not from real need.

I just received one from Shenzhen (at the MD price, thank you Shenzhen) and it includes a "credit card" Warranty Card with the S.N. on the card. The warranty is for TWO (2) years. Not bad, overall.

Here are my first quick impressions:
1. This is fresh outta the box and it is NOT burned in.
2. Whoa, this thing sounds refined. Liquid Gold isn't an unfair analogy. Woo-boy. NICE. I'm driving my newest pair Senn 650's (tied for my all-around favorite 'phone, and probably one of the harder to drive flavors in my collection.)
3. It's not playing nice with my FiiO K5/E17K DAC. Power it has in plentitude but I'm having to pre-amplify it with my K5's (NOT the E17k's) HP out. It sounds lovely with the balanced 3.5mm to XLR ins and virtually identical through the unbalanced RCA inputs but you can open the (very cool) level control all the way to get the exact same (underwhelming, to be plain) level, which is not what I've come to expect using my Lyr 2 as an arbitrary reference. (The Lyr 2 is nothing if not, er, Ballsy.) If you push it hard enough from the rear, it outputs like crazy and has seemingly inexhaustible headroom. (It'll play louder than I will tolerate for any length of time and it'll do it absolutely cleanly.) But my PC/FiiO K5/E17K line outs won't get it done by themselves. Maybe there's an internal gain setting nobody's talked about yet. (There are three on the front panel, and it never comes off of the highest one.) I'm going to contact Shenzhen about it. I'd suspect the FiiO (gains on high through the HP out) except it drives the 650's pretty well on its own. It doesn't sound as luxuriant as the H20 (using that or any other input pathway) but even at the Massdrop price, that was not something I expected. When the K5's in USB DAC mode, No line level gain (or tone/balance) adjustments work unless I'm reading/doing something wrong. (I ran the DAC flat, but again, it shouldn't have mattered.) I think it almost has to be the FiiO's fault. The 650's aren't featherweights to drive, but they're not Staxes either. It takes voltage in to get voltage out. (But boy, WHEN you do...) Either a bunch of people have it and are sitting on their experiences or I'm the first to "eat" the aforementioned bullet. I have a D50 (and a Lynx Hilo for the AD side) on the way and that's likely going to be my very likely stopping point for personal/PC audio, at least for a pretty good while. Those will tell the story, but I think the Lynx will take longer to integrate into my PC setup.

 

[Zennheiser]

I just received one from Shenzhen (at the MD price, thank you Shenzhen) and it includes a "credit card" Warranty Card with the S.N. on the card. The warranty is for TWO (2) years. Not bad, overall.

Here are my first quick impressions:
1. This is fresh outta the box and it is NOT burned in.
2. Whoa, this thing sounds refined. Liquid Gold isn't an unfair analogy. Woo-boy. NICE. I'm driving my newest pair Senn 650's (tied for my all-around favorite 'phone, and probably one of the harder to drive flavors in my collection.)
3. It's not playing nice with my FiiO K5/E17K DAC. Power it has in plentitude but I'm having to pre-amplify it with my K5's (NOT the E17k's) HP out. It sounds lovely with the balanced 3.5mm to XLR ins and virtually identical through the unbalanced RCA inputs but you can open the (very cool) level control all the way to get the exact same (underwhelming, to be plain) level, which is not what I've come to expect using my Lyr 2 as an arbitrary reference. (The Lyr 2 is nothing if not, er, Ballsy.) If you push it hard enough from the rear, it outputs like crazy and has seemingly inexhaustible headroom. (It'll play louder than I will tolerate for any length of time and it'll do it absolutely cleanly.) But my PC/FiiO K5/E17K line outs won't get it done by themselves. Maybe there's an internal gain setting nobody's talked about yet. (There are three on the front panel, and it never comes off of the highest one.) I'm going to contact Shenzhen about it. I'd suspect the FiiO (gains on high through the HP out) except it drives the 600's pretty well on its own. It doesn't sound as luxuriant as the H20 (using that or any other input pathway) but even at the Massdrop price, that was not something I expected. When the K5's in USB DAC mode, No line level gain (or tone/balance) adjustments work unless I'm reading/doing something wrong. (I ran the DAC flat, but again, it shouldn't have mattered.) I think it almost has to be the FiiO's fault. The 650's aren't featherweights to drive, but they're not Staxes either. It takes voltage in to get voltage out. (But boy, WHEN you do...) Either a bunch of people have it and are sitting on their experiences or I'm the first to "eat" the aforementioned bullet. I have a D50 (and a Lynx Hilo for the AD side) on the way and that's likely going to be my very likely stopping point for personal/PC audio, at least for a pretty good while. Those will tell the story, but I think the Lynx will take longer to integrate into my PC setup.

Follow up: I keep reading about people who get review samples to keep who do reviews. (How does one get signed up for THAT? LOL...)

 

[Zhangshan]

Erratum on H20 parameter translation errors

Due to our negligence in translation, the H20 headphone amplifier had an error in the nominal headphone output impedance parameter, which is now corrected as follows:

The first published parameter has the following translation error:
Front analog output (XLR): Output impedance 200Ω

The H20 has a built-in preamplifier function. This output port is on the rear panel. The impedance description of the previous translation error actually refers to the impedance of the preamplifier output.
We previously mislabeled the output as 'preout'. But the translator misunderstood outlet became the front panel.

Corrected hereby, the actual parameters as shown below:

And sincerely apologize to all users and people who care about our products.

 

[Zennheiser]

Followup-Followup: One important point I forgot to mention is I'm using the stock unbalanced 1/4" 650 cables. I was able to try both of the analog input XLR's but I've done nothing with respect to using the XLR preamp outputs. Yet.

 

[Alcophone]

Erratum on H20 parameter translation errors

Due to our negligence in translation, the H20 headphone amplifier had an error in the nominal headphone output impedance parameter, which is now corrected as follows:

The first published parameter has the following translation error:
Front analog output (XLR): Output impedance 200Ω

The H20 has a built-in preamplifier function. This output port is on the rear panel. The impedance description of the previous translation error actually refers to the impedance of the preamplifier output.
We previously mislabeled the output as 'preout'. But the translator misunderstood outlet became the front panel.

Corrected hereby, the actual parameters as shown below:

And sincerely apologize to all users and people who care about our products.

Thanks for the update and welcome to Head-Fi! Are you trying to get this fixed on Massdrop as well?

So before it said 200, now it says 100 (for the rear XLR). I guess either is fine, but that sounds like it was two errors in one.

Also, the low gain 6.35mm output has 50 ohms, while the high gain 6.35mm has 0.05 ohms? Is that right?
I would have used the low gain output with more efficient headphones, which usually are around 32 ohms, so not suitable for a 50 ohms output.

 

[BassDigger]

Erratum on H20 parameter translation errors

Due to our negligence in translation, the H20 headphone amplifier had an error in the nominal headphone output impedance parameter, which is now corrected as follows:

The first published parameter has the following translation error:
Front analog output (XLR): Output impedance 200Ω

The H20 has a built-in preamplifier function. This output port is on the rear panel. The impedance description of the previous translation error actually refers to the impedance of the preamplifier output.
We previously mislabeled the output as 'preout'. But the translator misunderstood outlet became the front panel.

Corrected hereby, the actual parameters as shown below:

And sincerely apologize to all users and people who care about our products.

Hello, and welcome. Who are you? A new (Gustard) employee, or just someone helping out?

Anyway, I thought that it was a translation error (i think that I said so, a few posts back): it's what made the most sense.

I'm very happy with my new (considerably less expensive) amp, so I won't be trying the H20 anytime soon. But, it's still interesting to read people's impressions of it, especially when it seems that it may be living up to (my) expectations.

Good stuff!

P.S. One query: Are the figures the correct way around, for the 6.5mm (L & H) single ended outputs? I assuming that L = low impedance, and H = high.

 

[sahmen]

2. Whoa, this thing sounds refined. Liquid Gold isn't an unfair analogy.

Could you kindly elaborate on this highlighted part? How fair is the comparison, especially, if you're familiar with the sound of the liquid gold? Thanks.

 

[gulakpii]

P.S. One query: Are the figures the correct way around, for the 6.5mm (L & H) single ended outputs? I assuming that L = low impedance, and H = high.

The 6.35 jacks marked L and H are for Low and High impedance (not "gain") phones.
However, I like it better when I plugged in my AKG K712 (62 ohm) into the H socket.