• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Topping DX3 Pro+ with Headphones with Low Impedance and High Sensitivity

dodecahedron

Member
Joined
Mar 31, 2021
Messages
12
Likes
2
After reading a lot of confusing comments about the Topping DX3 Pro+'s limited support of low impedance headphones, I’m trying to figure out if I will run into any clipping issues (or protection circuit issues) with that amp if I pair it with my Audeze LCD-X headphones. Here are my rudimentary calculations:

The LCD-X has an impedance of 20 ohms, and a 103 dB/1mW sensitivity.

Amir’s graph seems to show clipping (or triggering of the protection circuit) at about 3Vrms for that impedance.

index.php


According to Headphonesty’s headphone power calculator (https://www.headphonesty.com/headphone-power-calculator/), 3Vrms for these headphones (using 399mW) should be able to drive the headphones to a loudness of 129 dBSPL.

So I assume that even with an EQ with a large preamp (around -10dB), I should have more than enough headroom for me to listen to music at normal levels and never experience any clipping or engaging the protection circuit.

Are my assumptions correct? I’m new to these types of calculations, so I would greatly appreciate any feedback or corrections.

Thanks in advance!
 

catharsis

Member
Joined
Jul 20, 2022
Messages
5
Likes
3
That's the same way I see it.
 

twsecrest

Addicted to Fun and Learning
Joined
Nov 27, 2018
Messages
754
Likes
246
Location
California
I found one listing that says the Topping DX3 Pro+ has an output impedance of 20-Ohms.
Found another one that lists it a >1-Ohm.
At most I would expect a bloated (louder, less detailed) bass, but I would not expect a clipping issue.
 

Jimbob54

Master Contributor
Forum Donor
Joined
Oct 25, 2019
Messages
9,594
Likes
12,466
I found one listing that says the Topping DX3 Pro+ has an output impedance of 20-Ohms.
Found another one that lists it a >1-Ohm.
At most I would expect a bloated (louder, less detailed) bass, but I would not expect a clipping issue.
20 ohm is the rear rca output impedance. Less than 1ohm for the headphone output
 

Attachments

  • Screenshot_20220827-200719.png
    Screenshot_20220827-200719.png
    736.1 KB · Views: 39
OP
dodecahedron

dodecahedron

Member
Joined
Mar 31, 2021
Messages
12
Likes
2
Well, since my original post, I did buy the Topping DX3 Pro+ and I have had zero issues with using it with my LCD-X's. It gets very loud even at low gain.
 

MysterE

Member
Joined
Oct 2, 2019
Messages
17
Likes
2
Well, since my original post, I did buy the Topping DX3 Pro+ and I have had zero issues with using it with my LCD-X's. It gets very loud even at low gain.
How have you found the combination? Have you compared it with any other amplifiers/DACs or with other headphones? I'm looking at getting one myself and have the LCD-X too :)
 
Top Bottom