SMSL SH-9 THX Headphone Amplifier Review

[Music1969]

Can it though? Pretty much all recent Topping amps have binned volume pots for very good channel matching. Not a problem in practice.

What do you mean by binned volume pots?

How is their analogue volume control done?

 

[Veri]

What do you mean by binned volume pots?

How is their analogue volume control done?

Binned as in they keep the well balanced ones and discard the worse performing ones. That is the process of binning.
Still not as precise as digital volume but precise none the less. Digital volume usually has more self-noise.

 

[Music1969]

Still not as precise as digital volume but precise none the less.

And not as good as the SH-9's ...

Issue is minimised if you use the Topping gain options of course but the issue doesn't exist with the SH-9 and SP400 of course.

 

[jannek]

But as I wrote: "(or the different power offered by SH-9 at the different impedances)"

i.e. what headphones actually needs more power than this (objectively) - or is it just that people subjectively want more power?

View attachment 115821

These power specs are almost exactly double of that measured by @amirm - per channel. Can anybody please explain?

Is this only dependant of supplied signal voltage in the measurement?

 

[Music1969]

These power specs are almost exactly double of that measured by @amirm - per channel. Can anybody please explain?

Power is written by the manufacture as "x2" but this should be interpreted as "into 2 channels" or "each channel"

 

[jannek]

This explanation is exactly the wrong way round.

SMSL states 3Wx2@32R, 440mWx2@300R.
Amir measured 1,7W@32R, 226mW@300R. Per channel as far as I know, so also "x2" per device.

You see what I mean?

Same thing was already here with explanation in posts 16-18.

Why do they seem to pimp power specs by supplying voltages to an amp that no regular DAC puts out? 9V on RCA?!

 

[somebodyelse]

Amirm quotes power at the point where the distortion starts to shoot up, which is unusual. Manufacturers usually quote power at a particular distortion level somewhere further up the line as it's rising quite steeply, and this can easily be a lot higher. The manufacturer should state the distortion level and frequency (or frequency range) as well as the load, but marketing often want the simpler presentation with those details left out.

 

[jannek]

Amirm quotes power at the point where the distortion starts to shoot up, which is unusual. Manufacturers usually quote power at a particular distortion level somewhere further up the line as it's rising quite steeply, and this can easily be a lot higher. The manufacturer should state the distortion level and frequency (or frequency range) as well as the load, but marketing often want the simpler presentation with those details left out.

It's not the specification at 1%THD alone. Look here.

 

[Human Bass]

Bump because being 60 bucks less than the a30prp really makes it tempting.

 

[somebodyelse]

It's not the specification at 1%THD alone. Look here.

You mean that it needs 3V to achieve rated output, not 2V, or 0.7V if we go back to pre-CD days?

 

[jannek]

Yes. Which DAC (or other source) puts out one more than the standard 2 Volts on RCA? Let alone 7 volts more?

 

[Veri]

Yes. Which DAC (or other source) puts out one more than the standard 2 Volts on RCA? Let alone 7 volts more?

Plenty of them go up to 2.1-2.3V (Loxjie D30 is 2.3V as an example). A bunch of DACs have pre-amp mode which can go higher (SMSL M400 and SU-9 go up to ~2.7V, Gustard X16 supposedly can go up to 3.3V, Chord Mojo/Qutest can output up to 3.0V, ...)

 

[jannek]

OK, didn't know that. Everything I found has 2V straight in it's specs.

 

[Veri]

OK, didn't know that. Everything I found has 2V straight in it's specs.

Most are ~2.0-2.1V nominal output that's the standard. Some recent DACs push out more to have better distortion specification at maximum output. Most headphone amps can take the increase in voltage anyway. Some speaker amps could be overloaded with >2.0V input.

 

[somebodyelse]

You'll find the other side of the problem if you look at the 3E all-in-one amps - they aimed for getting full output with typical phone headphone sockets, but that means the input ADC overloads if fed from a DAC with a 2V output. There isn't an answer that's universally right unfortunately.

 

[Human Bass]

Considering the resistor ladder volume and being 60 less, it is reasonable to believe this is more bang for the buck than the a30pro?

 

[hawk01]

Considering the resistor ladder volume and being 60 less, it is reasonable to believe this is more bang for the buck than the a30pro?

i may be treading that path anytime soon. would have wanted the A30pro but i see no merits for paying $60 more other than the additonal output which i may not even need or use as my headphones are easy to drive. i am more into IEMs which warrant the merit of the premium volume control over the extra output. it would have been better if they implemented the 3-gain options but i suppose the ladder type volume control more than addresses those concerns.

 

[Human Bass]

i may be treading that path anytime soon. would have wanted the A30pro but i see no merits for paying $60 more other than the additonal output which i may not even need or use as my headphones are easy to drive. i am more into IEMs which warrant the merit of the premium volume control over the extra output. it would have been better if they implemented the 3-gain options but i suppose the ladder type volume control more than addresses those concerns.

I got it with a 30 dollars coupon, so 90 less than the a30pro, it became a no-brainer

 

[Daniel82]

Hi guys, I would like to know if anyone is running a Hifiman HE6SE on the SH-9 and the power is sufficient? I bought the combo of SU-9 + SH-9 last month and the power is more than sufficient for my Sennheiser HD650 and Audioquest Nighthawk.

But now I would like to buy another magnetostat and would like to order the HE6SE, but am not sure if the power is enough. Hifiman writes at least 2 watts per channel at 50 ohms. Unfortunately, the technical data from Smsl does not say how much the SH-9 performs at 50 Ohms.

Annoy me a little not to have bought the combo of Smsl M400 + SP400 or Gustard X16 + H16.

 

[Human Bass]

Hi guys, I would like to know if anyone is running a Hifiman HE6SE on the SH-9 and the power is sufficient? I bought the combo of SU-9 + SH-9 last month and the power is more than sufficient for my Sennheiser HD650 and Audioquest Nighthawk.

But now I would like to buy another magnetostat and would like to order the HE6SE, but am not sure if the power is enough. Hifiman writes at least 2 watts per channel at 50 ohms. Unfortunately, the technical data from Smsl does not say how much the SH-9 performs at 50 Ohms.

Annoy me a little not to have bought the combo of Smsl M400 + SP400 or Gustard X16 + H16.

Amir measured the power as 1.7watts at 33ohms, so it would be a bit underpowered for the hifiman. The A30pro will be more ideal