Review and Measurements of SMSL SP200 THX HP Amp

[Flognarde]

Thank you for the answers... Not sure to understand the full extend of the solutions you presented. Being under warranty, I won't do anything that is not reversible. If I just could find a way to make the knob harder to move, it would be an improvement.

 

[gino1961]

Thank you for the answers... Not sure to understand the full extend of the solutions you presented. Being under warranty, I won't do anything that is not reversible. If I just could find a way to make the knob harder to move, it would an improvement.

to put a so-called passive preamp in front of the amp and set the SMSL internal pot wide open. In this way you will control the volume with the external attenuator
https://www.amazon.com/Nobsound-Pre...keywords=passive+preamp&qid=1617550921&sr=8-3

if you use balanced connections you have to look for a balanced passive preamp
And if you used a stepped attenuator you will have perfect channel balance and a more better sound. As i said i did it and did not believe my ears ...
and it was a diy solution. A stepped attenuator made with holco resistors in series ... so not the best solution technically. The ladder type are the best ... you will have only one very high quality resistor in series with the signal ... the highest transparency possible (i.e. less noise and distortion added)
And in this way you wil not touch the unit at all ... all external By-passing the internal pot is not essential

 

[Flognarde]

Thank you, if you could recommend to me a good XLR passive pre-amp, I would be nice.
What about this one ? https://www.audiophonics.fr/en/prea...ter-rca-to-xlr-xlr-to-rca-silver-p-12360.html

 

[Flognarde]

I guess this one would be ideal ... It's over 1000€ !

 

[gino1961]

Thank you, if you could recommend to me a good XLR passive pre-amp, I would be nice.
What about this one ?
https://www.audiophonics.fr/en/prea...ter-rca-to-xlr-xlr-to-rca-silver-p-12360.html

i see your point ... XLRs are indeed more complicated. They have four channels ... i guess your source has XLR outs.
I have experience only with unbalanced passive preamp.
On principle this should be a superior one
https://www.audiophonics.fr/en/prea...sistor-volume-controller-xlr-rca-p-13183.html
impedance matching is critical. And it is not declared in the specs.
If your source has also very good unbalanced out you could try the unbalanced inputs on the SMSL. Probably noise will be a little higher ?
I am sorry but for XLR i think it is more critical I do not see many balanced passive preamp ... there must be a reason. Sorry i did not think about XLR. I have used only unbalanced sources and amps.

 

[gino1961]

I guess this one would be ideal ... It's over 1000€ !

Nice ... have you tried the RCA connections on the source and SMSL ? maybe they are also very good ? that will simplify a lot.
Try that first. If they are much noisier or distorted then better to pass ...
Even if at the very first start of the thread the Reviewer notes very well that

My favorite, XLR inputs are included which can be of a great help in avoiding ground loops with your PC and DAC.

but to try also RCAs is not that difficult. You need just cables.
A good unbalanced attenuator should cost around 100-150 USD ... in a case i mean.

 

[Flognarde]

Nice ... have you tried the RCA connections on the source and SMSL ? maybe they are also very good ? that will simplify a lot.
.

The source is a SMSL SU-8 ... and I have 2 amps plugged to it ... My Marantz PM6005 which only takes RCA's and the SP200 with the XLR's ...
I could use a switch but now it would get more and more crowded...

 

[Flognarde]

Let's be honest, the sound improvement would have to be massive for me to spend 150€ on a "knob" on a 200€ Headamp !

 

[snowsurfer]

The source is a SMSL SU-8 ... and I have 2 amps plugged to it ... My Marantz PM6005 which only takes RCA's and the SP200 with the XLR's ...
I could use a switch but now it would get more and more crowded...

Just reduce the volume on the SMSL SU-8, it has more than enough headroom. I use mine at 35 volume out to the SP200 via XLR when using 150Ohm+ headphones, and at 30 volume when using IEMs, it works beautifully. The only issue with the volume knob is that it is too light, but that's not a huge problem. I don't see what you would gain by introducing another volume control between the SU-8 and the SP200 when you can do it on the SU-8...

 

[gino1961]

The source is a SMSL SU-8 ... and I have 2 amps plugged to it ... My Marantz PM6005 which only takes RCA's and the SP200 with the XLR's ... I could use a switch but now it would get more and more crowded...

Great source and interesting. Then as someone else is advising you could lower the dac output and using the xlr outs.
i am using a smaller/cheaper Sanskrit 10th directly to a power amp using the volume control on the dac and the result is quite nice.
Speaking of price you are right ... a good volume pot costs Therefore it is impossible to find one on a 200 USD amp.

 

[Flognarde]

I think I did not make myself understood clearly ... I have no sound or technical issues (even though a great passive pre-amp could improve sound) just a first world problem : how to improve the cheap feeling and action volume knob ?

 

[MediumRare]

In the interest of keeping this site Audio Science Review: there is no possible way - none - of improving the sound of this unit. It is instrument grade already. You can only make it audibly the same or worse.

 

[Flognarde]

In the interest of keeping this site Audio Science Review: there is no possible way - none - of improving the sound of this unit. It is instrument grade already. You can only make it audibly the same or worse.

My point was not to enter this debate ... Any actual change in sound can be recorded by an electronic analyser.

 

[SMSL-Mandy]

I have just bought one ... I am enchanted... It's minor detail but how come SMSL has validated such a poor action volume knob for production ? I ordered 2 new aluminium knobs but I am afraid it won't solve the issue. If I find someone to solder another potentiometer, what improved model would be compatible and would it solve the problem ?

This is related to the potentiometer inside, which is normal. It is not recommended to change the potentiometer inside by yourself.
This is a regular carbon film potentiometer. Thanks

 

[Flognarde]

This is related to the potentiometer inside, which is normal. It is not recommended to change the potentiometer inside by yourself.
This is a regular carbon film potentiometer. Thanks

As I mentioned before, I would never modify a device under warranty ...
By the the way, some viewers are looking for the characteristics of the potentiometer used in the SP200 for possible replacement.

 

[RobS]

Is there a teardown of this amp?

 

[Flognarde]

Is there a teardown of this amp?

... Kind of, go check on Head-Fi, confirming the use a cheap no-name potentiometer. Not certain an Alps of the same type would solve the issue with the action.

 

[gino1961]

I wonder if anyone owning this amp has tried the unbalanced inputs and with which results. Thanks

 

[ra990]

RCA inputs resulted in some noise, but only with volume turned all the way up. Switching to XLR eliminated any noise and it is perfectly silent.

 

[MOCKBA]

When it is under load and i listening to music, the heating is very small. But when it's on and idle, it feels hot. Some strange phenomenon.

The behavior is specific to Class A amplifier, but I doubt they use one. So more likely you should start to worry.