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SMSL HO200 Review (Headphone Amplifier)

Rate this amplifier:

  • Poor (headless panther)

    Votes: 7 3.1%
  • Not terrible (postman panther)

    Votes: 15 6.7%
  • Fine (happy panther)

    Votes: 109 48.9%
  • Great (golfing panther)

    Votes: 92 41.3%

  • Total voters
    223

EJ3

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I do - late at might, when everyone else is sleeping. Large, comfortable, nice-sounding wireless headphones, connected to an AppleTV unit via Bluetooth. :)
I resemble that remark (not often). Usually I am resembling "Be Proud, Play It Loud" (over speakers). But when I do use the headphones, they are a quite comfortable to me old set of SSENNHEISER TS180 wireless "open" headphones connected to wherever I move around within 10 meter's + of the base unit.
 

audiofun

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usually the dc protection routine takes time and amplitude to kick in. the technology is simple --- use an LPF to remove high frequency signal, and in which the capacitor will be charged until certain amount of voltage is reached, then the transistor will flip the relay. So the capacitor needs some time and voltage to charge. most of the time music is not full amplitude low frequency sine wave, and the amp should be able to accept normal music just fine. Here amir tries full amplitude sine wave sweep, and probably that's the reason it kicks in earlier than expected.

In real music this should never be a problem. If it's a problem, the music is mastered incorrectly.

If one really wants to improve it, the parameters used for dc protection needs to be adjusted --- this is an art of balance between overprotection vs underproduction. Unfortunately, contrary to Amir's belief, a firmware update is not sufficient to improve in this case. I believe the capacitor/resistor values need to be updated.

SMSL can update it for future batches for sure.
 
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Calleberg

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Why in tarnation is some kind of cross-feed not mandatory on dedicated headphone amps like this?
To me, that otherwise very well behaved unit, is utterly useless without it.
My only conclusion is; whoever designed this thing, does not listen through headphones a great deal.

Gave it a "not terrible" vote, because it isn´t terrible, just useless. :)

This is what I use, pretty basic, if it had a power switch (not kidding NO switch) the panther would be golfing
holograph.png
 
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audiofun

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Why in tarnation is some kind of cross-feed not mandatory on dedicated headphone amps like this?
To me, that otherwise very well behaved unit, is utterly useless without it.
My only conclusion is; whoever designed this thing, does not listen through headphones a great deal.

Gave it a "not terrible" vote, because it isn´t terrible, just useless. :)

This is what I use, pretty basic, if it had a power switch (not kidding NO switch) the panther would be golfing
View attachment 161666
there is no way to implement crossfeed in analog in a clean way. digital is certainly easier and of higher quality, and you can have more parameters for adjustments as well.
 

Calleberg

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there is no way to implement crossfeed in analog in a clean way. digital is certainly easier and of higher quality, and you can have more parameters for adjustments as well.

Yes way! One example is in my post :)
But as you say might be easier and definitely with more bells and whistles avaliable if made digitaly.

But I did not write " headphone amps like this" because I wanted to use as many words as possible :)

RME does this in their ADI dac, at least I asume its digitaly implemented, but it is a totally different animal.

You could of course do it for free with an app... with the associated can of worms of compatibility issues, etc.
 
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audiofun

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Yes way! One example is in my post :)
But as you say might be easier and definitely with more bells and whistles avaliable if made digitaly.

But I did not write " headphone amps like this" because I wanted to use as many words as possible :)

RME does this in their ADI dac, at least I asume its digitaly implemented, but it is a totally different animal.

You could of course do it for free with an app... with the associated can of worms of compatibility issues, etc.
analog crossfeed will make design more complex and you'll no longer have a good performing amplifier like HO200.
 

Calleberg

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How do I say "thats BS" in a nice way :)


The circuit itself is pretty simple.
It´s a defeatable frequency dependent filter(sort of the general idea with most filters :) ) partially connecting left and right channel together, consisting of, in total, 7 resistors and 4 capacitors (and the defeat button) so not very "complex". and the button itself is probably by far the most expensive component in that BOM.

What it also is, is a typical example of the old story: "tapping with hammer: $2, knowing where to tap $9,998

This:

There will be the equivalent of two discrete components extra in the signal path with the circuit active, and with sensible choice of components it´s not going to degrade the sound enough to be noticeable, let alone degrade it to the point of no longer being "good performing".

The change in perceived sound-stage however is very noticeable, it is not in loudspeaker territory, but moves the soundstage from inside your head to in front of you, and totally removes the weird feeling from instruments and voices mixed 100% to the Left or Right.
 

groot

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IMO headless is the best rating a headphone amp with no PEQ functionality can attain.

Headphone amps (and amps in general) don't implement PEQ because PEQ is a digital process, so its more appropriate to implement in the DAC. The RME ADI-2 DAC FS implements PEQ in the DAC; it does not have any analog input. The RME ADI Pro FS R does have Analog inputs and can apply PEQ to them, but at an additional $700 to pay for the A/D converter.

Your position that all headphone amps are useless unless they contain A/D-D/A conversion (or at least D/A) is little like saying all cars are useless because they can't float on water. That's what boats are for. The RME's are amphibious vehicles, and I love them for it, but I can still appreciate a nice car or nice boat for being good at what they are designed to do.

PEQ is expensive to implement in silicon right now but in a few years it probably will be built into all the DACs. The Qudelix-5K is showing the way (it's only ~$100 vs. $1200 for the RME, but you have to supply the computer (phone) to run the user interface ;)). Computer software like Roon and SoundSource are making PEQ more accessible to use (it's been built into the Mac OS for like, forever as a plug-in but the UI is painful o_O).

I can appreciate that you perceive having a separate DAC and amp as a waste of space, but I can't agree that an amp is useless because it's just and amp.
 

Count Arthur

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Why in tarnation is some kind of cross-feed not mandatory on dedicated headphone amps like this?
Not everyone likes crossfeed.

One of the first electronics projects I completed was a passive crossfeed based on the Meier Audio design, using a selector for three different levels of crossfeed: https://headwizememorial.wordpress.com/2018/03/09/an-enhanced-bass-natural-crossfeed-filter/

I've also tried digital crossfeed, on the RME ADI-2 and within JRiver.

In every case, I found that I preferred the sound without any crossfeed.
 

Calleberg

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Not everyone likes crossfeed.

One of the first electronics projects I completed was a passive crossfeed based on the Meier Audio design, using a selector for three different levels of crossfeed: https://headwizememorial.wordpress.com/2018/03/09/an-enhanced-bass-natural-crossfeed-filter/

I've also tried digital crossfeed, on the RME ADI-2 and within JRiver.

In every case, I found that I preferred the sound without any crossfeed.

Hence, the defeat button :) But as stated before, by me and others most useful for those who appreciate it. And the bulk of the cost will be in said button, so only a small impact on Production cost. The challenge is, as with so much else in the implementation.

I have not heard the Meier or RME crossfeed, but they are supposedly pretty OK, so sure XFeed is probably not your cup of tea, which is fine and makes your life somewhat easier. ;)
 
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Haruko

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crossfeed sounds terrible to me (i tried Meier Crossfeed) it sounds like when I want to make things mono with some plugin at DAW and leave it at 20% wet or so...
 

Calleberg

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Headphone amps (and amps in general) don't implement PEQ because PEQ is a digital process, so its more appropriate to implement in the DAC. The RME ADI-2 DAC FS implements PEQ in the DAC; it does not have any analog input. The RME ADI Pro FS R does have Analog inputs and can apply PEQ to them, but at an additional $700 to pay for the A/D converter.

Your position that all headphone amps are useless unless they contain A/D-D/A conversion (or at least D/A) is little like saying all cars are useless because they can't float on water. That's what boats are for. The RME's are amphibious vehicles, and I love them for it, but I can still appreciate a nice car or nice boat for being good at what they are designed to do.

PEQ is expensive to implement in silicon right now but in a few years it probably will be built into all the DACs. The Qudelix-5K is showing the way (it's only ~$100 vs. $1200 for the RME, but you have to supply the computer (phone) to run the user interface ;)). Computer software like Roon and SoundSource are making PEQ more accessible to use (it's been built into the Mac OS for like, forever as a plug-in but the UI is painful o_O).

I can appreciate that you perceive having a separate DAC and amp as a waste of space, but I can't agree that an amp is useless because it's just and amp.


I Somewhat agree with you, A quality Analog multiband PEQ would probably Cost more than the Headphone amp electronics itself, and performance would probably still not be on par with digital. But even Digitaly implemented Multiband PEQ would be over the top for a Headphone use ONLY application, for most people.

Simply because it is super hard to tune such a PEQ to perfection by ear.(even if you have the measurement gear, earshapes differs and that has some bearing on percieved tonal balance too)
But as soon as you go digital and DSP, the PEQ kind of comes with that package.

Point is a simple analog 2-3 band baxandall type tone control might be sufficent, no need to go all PEQ crazy for dedicated Headphone use.

If your HP amp, DAC & DSP combo also serves main preamp duty its a different ballgame altogheter and not even the RME has enough bells and whistles:)
 
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Svperstar

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Another "upgrade" from my SMSL SP200 where I highly doubt I could tell any difference.
 

nakanock

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My HO200 has a small sound from the XLR input even when the switch selects the RCA input, is that normal?
 

groot

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My HO200 has a small sound from the XLR input even when the switch selects the RCA input, is that normal?

I believe it is normal (and common) for high gain amps with multiple analog inputs. The signal from one input bleeds over into the second because of the proximity of the signal paths. But you should only perceive it when the amp is set to high gain, the volume is turned way up and there isn't anything playing on the selected input. I wouldn't consider it a flaw if you only hear it in that scenario.

I know the ZenCAN does the same thing on its high gain setting (others have noted it as well), but other amps with lower gain potential might not do so audibly.

This is one reason you might use an external pre-amp for source selection. A pre-amp signal chain does not run at a high enough voltage to have the signals bleed over audibly like that, and the amp only gets the single signal from the pre-amp. { I'm not recommending a pre-amp, just saying that it addresses that issue. }
 

nakanock

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I believe it is normal (and common) for high gain amps with multiple analog inputs. The signal from one input bleeds over into the second because of the proximity of the signal paths. But you should only perceive it when the amp is set to high gain, the volume is turned way up and there isn't anything playing on the selected input. I wouldn't consider it a flaw if you only hear it in that scenario.

I know the ZenCAN does the same thing on its high gain setting (others have noted it as well), but other amps with lower gain potential might not do so audibly.

This is one reason you might use an external pre-amp for source selection. A pre-amp signal chain does not run at a high enough voltage to have the signals bleed over audibly like that, and the amp only gets the single signal from the pre-amp. { I'm not recommending a pre-amp, just saying that it addresses that issue. }
Thank you. I understood this is a common problem with other models.
This time, when I selected high gain, I could hear another input source despite the minimum volume and it sounded weird because the sound was mixed.
 

jimboaz

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As you say, the performance is very good, but the thing is a complete ergonomic and design disaster.

There's so much wrong, I don't know where to start. Will they ever learn? I doubt it. SMSL are one of the worst and can always be counted on for a good laugh.

Maybe one day they will ready for prime time- I hope so. That time when people look at their product as aspirational, highly performant and oozing quality. They have one of the three qualifiers. The other two, not so much.
Really - so what is soo much better - and why - for the price???
 

Joel

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It is 15% off in Amazon. Anyone got one?
I did. So far I like it and think I’ll keep it. Sound quality-wise, it isn’t a big upgrade from the Symphony Desktop I was using but it does have ridiculous amounts of power in comparison. Does anyone actually NEED the high-gain setting? I drive my AEON 2s at mid-gain comfortably at 11 o’clock on mid-gain.

I’m actually using the pre-amp function more and it works incredibly well there too.
 
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