SMSL SP400 Balanced Headphone Amplifier THX AAA

[vault108]

Some notes: Power cable is very short, like 3.5" feet. Turning volume make relay sound which can be annoying. Same remote is used for M400 and SP400. You switch between device with B/C button. Medium gain and High gain make no different to me. It seem to be louder/higher gain than THX887. Don’t have SP200 to compare.

 

[Artaois]

So I've seen the gain listed as 3db and 6db for high in product descriptions but towards the bottom of this page there is a gain control chart that says Bal in/Bal out equates to:
6.5db@GAIN L
9.5db@GAIN M
11.6db@GAIN H
For single ended its lists 0, 3.5, 5.3
Am I missing something? Whats the correct gain amount?

https://apos.audio/collections/brand-spotlight-smsl/products/smsl-sp400-thx-aaa-888-headphone-amp

 

[SMSL-Mandy]

So I've seen the gain listed as 3db and 6db for high in product descriptions but towards the bottom of this page there is a gain control chart that says Bal in/Bal out equates to:
6.5db@GAIN L
9.5db@GAIN M
11.6db@GAIN H
For single ended its lists 0, 3.5, 5.3
Am I missing something? Whats the correct gain amount?

https://apos.audio/collections/brand-spotlight-smsl/products/smsl-sp400-thx-aaa-888-headphone-amp

On balanced or unbalanced? The test conditions will affect the final result. Need to analyze.

 

[Artaois]

On balanced or unbalanced? The test conditions will affect the final result. Need to analyze.

All that was from the apos website. People seem concerned that it's not putting out proper volumes using balanced I believe.

 

[SMSL-Mandy]

SP400 output isn't low. It IS lower than the output of SP200.
Never in my life have I had an amp with TWICE the rated power of the amp its replacing, ended up being half as loud....
It does get plenty loud, just not as loud as SP200

This is normal, and the gain design of SP200 and SP400 is different. Can’t compare the volume on the same gain. And the volume does not mean the power.

 

[SMSL-Mandy]

All that was from the apos website. People seem concerned that it's not putting out proper volumes using balanced I believe.

Yes,
the balanced in/ balanced out data is:
6.5db@GAIN L
9.5db@GAIN M
11.6db@GAIN H

Recommend using the balanced input of SP400.

 

[Artaois]

Yes,
the balanced in/ balanced out data is:
6.5db@GAIN L
9.5db@GAIN M
11.6db@GAIN H

Recommend using the balanced input of SP400.

Like on the Focal Elex running from a M400 I was at 50 on high gain. That doesn't seem like a lot of headroom for higher impedance headphones does it?

 

[JB5150]

This amp is a joke.
I am returning it.

 

[JB5150]

Yes,
the balanced in/ balanced out data is:
6.5db@GAIN L
9.5db@GAIN M
11.6db@GAIN H

Recommend using the balanced input of SP400.

I bet this amp will “measure” great. There is little gain, which equates to less output volume. (And I bet class leading SINAD)
This amp at $600 is NOT as powerful as the $200 counterpart. Not sure what the goal here is, other than measurements.
Very disappointed.

 

[JB5150]

Like on the Focal Elex running from a M400 I was at 50 on high gain. That doesn't seem like a lot of headroom for higher impedance headphones does it?

Complete lack of headroom. My 1.1watt 10 year old Musical Fidelity amp gets louder. Shame on SMSL.

 

[Artaois]

I bet this amp will “measure” great. There is little gain, which equates to less output volume. (And I bet class leading SINAD)
This amp at $600 is NOT as powerful as the $200 counterpart. Not sure what the goal here is, other than measurements.
Very disappointed.

That's a decent gain. It just doesn't sound that high in reality.

 

[mkawa]

woah! with my elex i'm on low gain at 30. this is really odd to me.. the highest gain i've gone is mid-gain and that was only with 600o headphones

 

[Joaquinín]

I understand that, using it as a pre to feed active speakers (Kh-120 or similar), it´s lowish gain is not a problem? Contrary to the current contenders from Topping (A90, Pre90) and Gustard (H16), this one seems to have the right input impedance (47k, apparently for both balanced and unbalanced inputs?) for an old class-A tuner (Accuphase T-101). Am I wrong?
I am evaluating if the SP-400 would be a good option to use it as asource selector-volume control in my office (X-16 DAC to xlr, T-101 tuner to rca input).

 

[JB5150]

woah! with my elex i'm on low gain at 30. this is really odd to me.. the highest gain i've gone is mid-gain and that was only with 600o headphones

I do tend to listen very loud. And I use Roon which uses about -6db of Headroom Management.
this amp, doesn’t have enough power to satisfactorily drive my headphones WITHOUT at or near full volume.
SP200 in contrast, NEVER goes much above 50% on the volume knob before it’s too loud.
This amp IS NOT more powerful than the SP200.
Many people fell that the SP200 not being “true balanced” hinders it. Maybe so.
BUT the SP400 is not worth the $$ for me.

 

[Artaois]

woah! with my elex i'm on low gain at 30. this is really odd to me.. the highest gain i've gone is mid-gain and that was only with 600o headphones

Not a good sign. Wonder if there's some messed up unit's out there...

 

[NightlyNurse]

Not a good sign. Wonder if there's some messed up unit's out there...

I'm putting this message so I can monitor this. My SP400 doesn't get very loud. I'm ok with that but if it's defective I should probably get it swapped out

 

[labrasca]

I got the D90 and the SMSL 400 Stack. Love the DAC but the volume on the amp is definitely lower then the D90. I used a pair of Arya headphones on high gain, and 70-80 on the SMSL 400 amp. I run them with mid gain and 1-2 oclock on the D90 volume. I find the clarity/sound stage is great with SMSL DAC and D90. The one thing I like about the SMSL stack is over longer listening... it reminds me more of tube equipment. I find it to be a slightly warmer sound (esp vocals) and more intimate. Just my thoughts.. been out of Audio for many years and getting back in. Amazing how much things have changed. i Have my counterpoint preamp/nobis tube amp and that is my point of reference. New to headphones.

 

[rjley]

This amp is a joke.
I am returning it.

Already returned mine.

 

[SMSL-Mandy]

The S.M.S.L SP400 is designed for normal 16-300 ohm headphones. The gain design also belongs to the normal range.
If the impedance is greater than 1000 ohm headphones, needs a "special high voltage, high gain, low current" amp to drive, such as a tube special amp.
When the sound source is turned on to the maximum, the volume of SP400 is generally not very low. In a normal state.

 

[leben]

The S.M.S.L SP400 is designed for normal 16-300 ohm headphones. The gain design also belongs to the normal range.
If the impedance is greater than 1000 ohm headphones, needs a "special high voltage, high gain, low current" amp to drive, such as a tube special amp.
When the sound source is turned on to the maximum, the volume of SP400 is generally not very low. In a normal state.

No, Mandy. The point is you guys have claimed sp400 will have output power of 6W@32Ohm, which would drive even susvara to 115dBSPL just fine. But it seems in reality it doesn't live up to that at all. You've already did this kinda shady claim with your SH-9, which has approx. 1.7W@32ohm but was claimed to have 3W @ 32ohm. Topping as well did this with their L30. I kinda see where sbaf guys come from...