[john61ct]

Yes talking about the black & red HEL, designed "for gamers", although I ain't one, at all.

Even though I **do love** that big topside volume pot, I would really prefer something more "pants pocket" definition of portable, and spdif in/out would be nice.

Problem is, I **really** want the microphone flexibility, for podcasting, telephony / conferencing etc while my cellphone is busy acting as a DAP with a bunch of stuff hanging off its OTG dongle.

That together with the line level in & out, ability to be a full-gain preamp, really seem to add up to a Unique Selling Proposition.

Apparently as a headphone amp, handles HD650s just fine, I doubt I'll ever go any power thirsty / higher impedance than that.

Ignoring the DAC for now, but I guess if anyone can speak from experience about OPPO HA-2SE (wait and save those pennies!), Big Ego or even Topping D10 to compare, feel free to toss out other suggestions

[john61ct]

So, the question, if it isn't obvious, is

What are HEL's competitors **as a headphone amp** with good mic functionality? Taking my use case / preference details implied above into account, especially lower budget, $200-300 max I think for now.

The all in one package including a USB DAC feeding from a phone is great too though, don't get me wrong,

just **please** don't get bogged down in the "fancy DAC" comparison weeds, these old ears prolly can't hear much difference. . .

_______
My notes from the HEL spec sheets etc:

DAC / headphone amp, preamp
  big step up from Fulla 3
5 x 3.5 x 1.38” including knobs

can be just a headphone amp, or just a pre-amp
    with great volume attenuation
  source switcher between analog line input and the
  DAC: AKM 4490, AK4490
    USB input only, no digital output

very nice stereo-compatible analog **mic** preamp
  only active with USB DAC mode
  podcast-quality, home office conferencing
  for gaming headset, phone earbuds + mic
    electret desktop, ModMic 5 or lapel mic
  24-bit AKM ADC, OPA1662 pre-amp, own dedicated
    front-panel Alps pot for gain, adjust mic level

front switch between USB and line-level analog
  input via rear 3.5mm 1/8" jack
  also disables mic input, no DAC, amp only

volume pot Alps RK09, controls 3.5mm variable
  output for active speakers, or headphones

or as a pre-amp, feed a power amp; set gain low,
  raise volume all the way to the max, effectively
  becomes a line out. Can even boost from headphone jack if needed!

  high-quality TI OPA1662 filter amp stage op-amps
  output stage OPA1688 has feedforward
  precision thin-film resistors and film capacitors

powerful DC-coupled, high-current headphone amp
  Low/High Gain switch - 1 (0dB) or 5 (14dB)
  handles sensitive IEMs or low-efficiency planars
    1000mW into 32 ohms, 1200mW into 16 ohms
    200mW of power at 300 ohms, HD650s no   
    problem, even 300-ohm , planar magnetics

inserting headphones, disables analog outputs,
  enables mic output, over USB only?

USB input C-Media CM6631A
 
from tablets, or computers, Win10 24-bit/192KHz
  use WASAPI plugin for foobar2000

perfect for phones
    maybe requires UAPP, external hub power
    needs USB at true 2.1 amps

no optical in nor out, so no galvanic isolation?
   no coax SPDIF cable in or out either?
sophisticated USB power supply, bipolar +/-12Vp
  input 2+ amps

$189 new

[john61ct]

Oh, forgot to mention, along with at least "transportability", DC power is a must, if not USB powered.

Requiring plugging into a wall-wart is a dealbreaker for sure.

The device might come with one that's fine, but it **must** also be able to accept feeding off a battery back without any inverter in between.

Related: https://www.audiocircle.com/index.php?topic=170549.msg1805899#msg1805899

[jhm731]

Worth the extra money:

[DZetye]

second the Mojo by Chord.  Worth its weight in gold

[john61ct]

second the Mojo by Chord.  Worth its weight in gold

Worth the extra money:

[img]https://www.audiocircle.com/image.php?id=210454[/img

Yes, have read it's great, but had no idea about the microphone feature set being as good or better than HEL?

Edit: for more than double the price, no mic support, at all.

Can I use a headphone cable with a microphone?
No, Mojo only processes the outgoing audio signal and does not take a signal back to the phone.

Yes the optical inputs and internal battery are great?
And I'm sure the DAC is better, the amp might go higher-Z, but I had stated both those are irrelevant for this use case.

But thanks for the suggestion, looks like a great unit to look out for in future.

[Letitroll98]

Since the Mojo has been rejected by the op it's no big deal, but the Mojo is way over C&C pricing guidelines.

[john61ct]

What is C&C?

[charmerci]

What is C&C?

Post #24 , cheap & cheerful

https://www.audiocircle.com/index.php?topic=71233.20

[Letitroll98]

What is C&C?

Umm, the circle you're posting in.
Here's the guidelines:

https://www.audiocircle.com/index.php?topic=71233.0

Your post is perfectly placed in the C&C circle and we're about having fun with audio so nobody cares that the Mojo was mentioned, I'm just the speed cop that has to tell folks you're not getting a ticket for going 10mph over the limit, but I'm sitting here on the side of the road reminding people of the limit.

I haven't seen anything that matches the Hel on audio sites, I'm sure there are many on gaming sites.

[john61ct]

OK thanks for clarifying, I guess a circle is a sub, I like the personal level of forum culture here so far.

I also like those C&C guidelines personally, the Mojo really would be a stretch for me even if it did handle mic input.

I'm not about to go looking for an audiophile-oriented gaming forum for this topic; I just want audio types, to advise if I've missed something obvious in my research, so far Hel seems the way to go.

I get a great minimalist preamp/volume control, toss in a semi-portable headphone amp as well, and maybe the DAC will be good enough for me for long term.

_______
Topic tangent:
In my research I've discovered that most smartphones and some laptops sport a TRRS "4-pole" jack that supports both stereo in and stereo out on the one compact 3.5mm connection!

Anyone know if using that design's got any inherent SQ issues?

[Letitroll98]

I looked through the Topping, Sabaj, SMSL catalogs on HiFi Express and couldn't find any portables with microphone inputs like the HEL.  The Topping NX series uses the 2.5mm computer/phone connection.  I believe this goes through the computer or phone's sound processing while the OTG mini USB connection bypasses the internal sound cards, but I'm a ludite in regards to all that.  I use a Sabaj Da2 from my phone or computer and have no issues getting calls.

[john61ct]

Wow thanks for looking like that, interesting devices there!

The Topping NX series uses the 2.5mm computer/phone connection

Sorry can't find that detail?

> I'm a ludite in regards to all that.

Do you mean averse to that level of tech, or just not fully up to speed yet?

> I use a Sabaj Da2 from my phone or computer and have no issues getting calls

Dealing with multiple wires going to the phone seems a kludge, and I really hate speakerphone mode.

Especially driving or biking, I can't see holding it up to my mouth with the dongle swinging around, really just want to leave it flat down on the seat or table.

[Letitroll98]

More like don't care because I have no need for it rather than opposed, so I'll never be up to speed.  However I completely understand those always getting calls being interested in the tech.  Being old and retired reduces urgent phone calls to nearly zero.  My headphones cables weigh more than the Da2, I don't notice it's there, and for me there are no other cables.  I thought I'd find something quickly in the ChiFi catalogs to fit your needs, but apparently not.

[john61ct]

gotcha, thanks for trying

[john61ct]

The problem I have with the HEL is the fact that apparently when listening from the analog line inputs, the microphone amp get disabled?

This seems very odd to me, with a TRRS connection to the phone, could just switch the mic input from the A/D converter over to direct analog pass-through?

I've come across a whole new product category in "USB audio interfaces".

Focusrite Scarlett 2i2
Apogee Duet 
RME Babyface Pro FS
Steinberg UR22

But these are **so** focused on the A/D inputs, I suspect not so great as headphone amps until spending crazy big bucks.

The ability to go to high quality balanced XLR on the preamp outputs seems a good thing though?

[john61ct]

Good points made here

https://forum.hifiguides.com/t/syba-sonic-fulla-3-3-5mm-mic-input-dac-amp-recommendations/8073/2

Get a separate preamp / headphone amp, then look to one of these "audio interface" units to get best quality microphone input and DAC functionality.

But wow, for nomadic working from a backpack, sure violates KISS and what a mess of cable management. . .

[Letitroll98]

Reminds me of when I was a boy and we moved to Pittsburgh, a city that because of geography has no straight roads that directly go anywhere and there are at least a dozen bridges to cross on any trip.  My father stopped to ask for directions to some location and the man said, "Well stranger, you go on up this road and... no, that won't work.  If you head back that road you can... nope, can't go that way.   Lemme see... no, that bridge is closed.  Well sir, you cain't get there from here".

[Speedskater]

Yep, those Pittsburgh roads. We went to a wedding long before cell-phones. We called from a phone booth (remember those?) for final instructions. Even thou we were less than 2 miles from our destination, they sent a person to guide us, because the couldn't give us usable instructions over the phone.

[john61ct]

That's what they call "a long walk" in comedy circles

Actually this thread has been very useful, not just guiding my learning curve, thanks so much!

but, in focusing on that aspect of a good quality microphone preamp integrated with a headphone amp, I've discovered that obviously such a design serves such a small niche

that nothing is designed for "work from home" professionals who happen to care about SQ.

There's "gaming" products, which Schiit happened to target with HEL.

And there's the "audio interfaces" total overkill pricing if you want a powerful headphone amp in there that has proper voltage and impedance options to handle audiophile quality headphones.

Seems like a market gap opportunity there!

The ideal for me would be a small unit that is designed to accommodate a 3.5mm analog TRRS input, also 3-4 more TRS inputs, so can act as a source switcher, including ability to monitor / loopback for tone control e.g. Schiit Loki or a DSP.

OR switch overto digital I/O, primary being OTG / micro USB for digital comms with the host phone/tablet/computer, great drivers and buffering async / clocking etc needed for the USB data input.

In both cases enabling SOTA sound quality for both the audio-out and microphone-in.

Separate micro USB for power, clarifying that most phones may not provide enough, depending on the headphones used. Super powerful and flexible headphone amp section, also line out, ideally fixed and variable with gain.

Microphone stereo preamp accepting of any type mic hardware, excellent SQ for phone conferencing, live streaming, content creation, but without all those recording mixing features DAW integration from the "audio interfaces", PC stuff is so last century, this is a mobile fits in your pocket solution, and all features must be accessible with no CPU-host in sight, leverage the smartphone but not depend on it.

DAC also reached via SPDIF, both coax and TOSlink, ideally both inbound and out for passthrough /conversion any to any connector, to an outbound DAC, e.g. USB to optical converter.

Remote control via app, while we're at it wireless data stream, little micro USB phone dongle, lightning and USB-C adapter included. proprietary 2400Ghz protocol for lossles hires.

Or no dongle needed if you're willing to drop some bits and host device is BT compatible, select between aptX HD vs LL for movies (and games yes or LDAC

Icing on the cake, lots of analog outputs, also feed multiple amps / speakers including x.1 crossovers.

I know sounds a lot like Audio Interfaces, but oriented toward listening to music not recording or mixing it, and primarily a top-notch headphones amp.

Edited title to reflect this diversion of the thread topic.