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SPL Phonitor X *Updated* Review (DAC & Headphone Amp)

amirm

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A while ago I tested the SPL Phonitor X which did not do well. Turns out the DAC in that unit was the older generation. And I did not know about dip switches underneath the unit which sets the headphone gain. This review remedies both. New units sell for US $2,999 now.

This unit is in silver which makes it easier to see the labels:

SPL Phonitor X Review New DAC Headphone Amplifier.jpg


Needless to say this is a gorgeous looking desktop product, albeit a large one. Back panel shows that the unit can be used as DAC, pre-amp and/or headphone amplifier:

SPL Phonitor X Review back panel balanced New DAC Headphone Amplifier.jpg


In this review I focused on DAC and headphone amplifier subsystems.

Phonitor X New DAC Measurements
The new DAC indeed performs quite a bit better:

SPL Phonitor X Measurements New DAC Headphone Amplifier.png


Still, given the cost, the performance is quite low compared to even budget offerings:

Best combination dac and headphone amp reviewed.png


Baseline noise is rather high -- a problem that you will see in measurement after measurement:

SPL Phonitor X Measurements Dynamic Range New DAC Headphone Amplifier.png


SPL Phonitor X Measurements IMD New DAC Headphone Amplifier.png


Distortion is not competitive either:

SPL Phonitor X Measurements Multitone New DAC Headphone Amplifier.png


SPL Phonitor X Measurements THD+N vs frequency New DAC Headphone Amplifier.png

Jitter is excessive:

SPL Phonitor X Measurements Jitter New DAC Headphone Amplifier.png


Linearity is not great due to high level of noise:

SPL Phonitor X Measurements Linearity New DAC Headphone Amplifier.png


Headphone Measurements
I started with the DIP switches set to off which gives it the lowest gain (almost unity gain):

SPL Phonitor X Measurements Headphone Amplifier.png


SPL Phonitor X Measurements Balanced Headphone Amplifier.png


This is again well below where the front runners are:
best headphone amplifier.png


Noise performance once again is not great:

SPL Phonitor X Measurements SNR Balanced Headphone Amplifier.png


Frequency response is flat enough but I expect better:

SPL Phonitor X Measurements Frequency Response Balanced Headphone Amplifier.png


Most important here is the power vs distortion+noise. So let's start with 300 ohm load:

SPL Phonitor X Measurements Power into 300 ohm Balanced Headphone Amplifier.png


We have a ton of power here if you can tolerate higher noise and distortion.

Going down to 32 ohm load causes sharp increase in distortion and very early:

SPL Phonitor X Measurements THD 32 Balanced Headphone Amplifier.png


Sweeping the load we see how it doesn't low low impedances that demand current as opposed to voltage that it is designed to provide:
SPL Phonitor X Measurements Power vs load Balanced Headphone Amplifier.png


I am not happy with the sharp rise in distortion at lower impedances. Planar magnetic headphones are going to suffer. But if you have a 300 or 600 ohm headphone, this thing sings. And sings really loud!

Listening Tests
I started with my everyday Dan Clark Stealth headphone. Was saddened that anything past medium level of loudness resulted in audible distortion in the form of garbling. Its low impedance and demand for power is not a fit for Phonitor. I switched to Sennheiser HD 650 with its 300 ohm impedance and now the unit was happy to drive it to very loud volumes with excellent fidelity.

Conclusions
We have improvements across a number of areas here relative to the older unit I tested. Alas, the main story of this unit has not changed. Its design uses high voltage rails which means it is optimized to drive high impedance loads. With anything else, its performance suffers. Its DAC is now "fine" but nowhere near state of the art. Considering how much you are paying for this unit, you want to have much better performance than a unique niche. Yes, the case is lovely but you don't listen to the case.

I can't recommend the SPL Phonitor X. I hope they revamp this architecture and make it more performant.

------------
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JohnYang1997

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The 33ohm THD+N vs Power graph doesn't match the Sweeping the load graph. The latter graph showed less than 0.8W with 32ohm load.
Perhaps the load was still set on 300ohm for the 33ohm THD+N vs Power graph.

EDIT: The review has been updated since the post.
 
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304290

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I had a buddy years ago who was from the camp "the more you spend, the better it sounded". I was a bit disappointed even then when I came over to listen to it. I also remember he didn't keep it long lol.
 
OP
amirm

amirm

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The 33ohm THD+N vs Power graph doesn't match the Sweeping the load graph. The latter graph showed less than 0.8W with 33ohm load.
Perhaps the load was still set on 300ohm for the 33ohm THD+N vs Power graph.
Thanks. Thought that looked odd. Will retest when I wake up.
 

Azathoth

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I heard of the company back in the day through this video
This was the beginning of my audiophool years, before I took a more objective approach to the hobby. Those were the days.

But anyways, the thing looks gorgeous, and that alone with the VU meters and such subjectively wants me to have it on my desk.
 

YSC

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I don't really understand a part, in the 33ohm the max power with medium gain is 10W which is very high before distortion kicks in, so why using a low impedance planar will have the distortion kick in quickly? I thought in that case current should be ample before distortion???
 

Soniclife

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@amirm Did I miss the bit where you declare what the source of the product was?
 

JSmith

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measurement does not seem as 'pro' as its looks
Please clarify your position here... there's no point making little quips like this without any detail of what your concern is. Otherwise it may be interpreted as poor intent.



JSmith
 

Vict0r

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Now imagine Topping making a product with the looks of an SPL. A boy can dream.
 

_theLaughingman

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Eww who created this mess. Yikes
 

nyxnyxnyx

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One of the popular "summit-fi" gears that I used to hear here and there, I always thought that it had to be a bit overrated at the very least - given how popular and "recommended" it was (Don't mean it's bad, it's just more famed than what it should be).

The case is absolutely gorgeous and maybe it's the visual "performance" that attracted so many gear lovers. Maybe if they can cut the DAC and some features out of this case, decrease the price significantly, then I can see this amplifier selling as a hot cake.

Thanks for the review Amir!
 
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