Help with matching for Audeze LCD-2c

[zhenshen]

Hello!
First off, mind my imperfect English as it's not my first language.

I'm currently building an audio system and I need some advices.
The equipment I came up to:
- Turntable Audio-Technica AT-LP5x
- MC cartridge Audio-Technica PTG33/II
- Phono preamp NAD PP2e
- Interface Focusrite 6i6 2nd gen (which I primarily use as an output for PC)
- Headphones Audeze LCD-2c

Would an amplifier be highly desirable for LCD-2c with the given setup as a replacement for the interface? From what I've found on internet, the output impendace should be less than 1/8 of headphones impendance which is <9ohm in case of LCD-2c. Headphones output impendance of my interface is 10ohm. The matter of concern for me is not the presumably miniscule discrepancy of ~1ohm, but the potential difference in sound with an amp like Schiit Lyr 3.

Also frequency response of the headphones is 10-50000Hz and frequency response of the interface is 20-20000Hz. Can someone clarify to me how these specifications correlate? Does this mean that my interface is underwhelming to match the LCD-2c's capabilities in that parameter? As I understand, the lesser the diapason of frequencies, the worse is clarity of scene and readability of instruments in a track, right? These are crucial aspects for me.

If you have any off-topic advices (e.g. about finding a good combination of phono preamp and cartridges), please, feel free to share.

Thank you!

 

[RickSanchez]

Welcome to ASR.

You are correct, the output impedance of the 6i6 is a little higher than one might want in general but it'll be fine for your headphones. (See the "output resistance / damping factor" section of this review.) Unfortunately we don't have measurements of the headphone section of the 6i6 (gen 2). What I've seen on ASR is that some of the better audio interfaces have headphone amp sections that are not great. For example:

• Motu M4: https://www.audiosciencereview.com/forum/index.php?threads/motu-m4-audio-interface-review.15757/
  • "The headphone amp is the weakest part but still it serves to be usable."
• Focusrite Scarlet 2i2 (gen 3): https://www.audiosciencereview.com/...rlett-2i2-audio-interface-gen-3-review.10187/
  • "The only item performing well below expectation is the headphone amplifier."

Are you having any issues driving these headphones to high SPLs with the 6i6?

 

[zhenshen]

Welcome to ASR.

You are correct, the output impedance of the 6i6 is a little higher than one might want in general but it'll be fine for your headphones. (See the "output resistance / damping factor" section of this review.) Unfortunately we don't have measurements of the headphone section of the 6i6 (gen 2). What I've seen on ASR is that some of the better audio interfaces have headphone amp sections that are not great. For example:

• Motu M4: https://www.audiosciencereview.com/forum/index.php?threads/motu-m4-audio-interface-review.15757/
  • "The headphone amp is the weakest part but still it serves to be usable."
• Focusrite Scarlet 2i2 (gen 3): https://www.audiosciencereview.com/...rlett-2i2-audio-interface-gen-3-review.10187/
  • "The only item performing well below expectation is the headphone amplifier."

Are you having any issues driving these headphones to high SPLs with the 6i6?

The thing is that the headphones are yet to be delivered to my place, so at this moment I can't tell how they perform with 6i6. I had a chance of listening to LCD-2c from a digital source a year or so ago, and they were plugged into an amp (I can't remember which one exactly). I liked them a lot and firmly decided to buy them when possible. Now while they are being delivered to me, I'm in advance looking for a fitting amp, because I suppose 6i6 won't be enough for LCD2-c based purely on technical specs.

What parameters should I look at when choosing? And how these parameters should match between different parts of an audio system? Most obvious for me are: impendance, power and frequency response. This is the general question I'm looking for an answer to, since it's not possible for me to test all kinds of different audio equipment by myself before purchasing.

Thanks for the response.

 

[RickSanchez]

So for power requirements on the amp this tool may be useful for you: Headphone Power Calculator - Headphonesty You can plug in the specs on your headphones + the max SPL you want to get and it will calculate how much power (wattage, voltage, current) you need from your headphone amp. I don't think your LCD-2c's are particularly hard to drive, but see how those power requirements line up with the 6i6 output power specs.

What parameters should I look at when choosing?

One way to approach this is to look at how Amir does his measurements for headphone amps. Try, for example, comparing a good amp to a bad one:

• Good: https://www.audiosciencereview.com/...thx-887-balance-headphone-amp-new-champ.8942/
• Bad: https://www.audiosciencereview.com/...and-measurements-of-schiit-valhalla-amp.8273/

You'll get a better sense of headphone amp measurements that way, things like SNR, output power, frequency response, distortion vs. power. Unfortunately we don't have measurements for the 6i6 so it's incredibly difficult to know how that device performs.

Another resource for you:

Audio Electronics Review and Measurements Index

Master table and index of all audio equipment reviews and measurements.

www.audiosciencereview.com

For filters you can use:

• Type = "Headphone Amp (Dedicated)" + "Headphone Amp (Multifunction)".
• Recommended = Yes
• Price = (whatever your limit is)

It's not complete; it's missing review for the last ~6 months or so. But it can give you a good start.