T30 Freq. Response: Excellent

[MRC01]

Today I got my new T30. I loaded the 1.71 firmware and switched it to UMS mode. Then I measured the frequency response. It is quite good - far better than I expected and much better than CNET measured other iRiver players. In fact its freq response is better than many full size audiophile CD players!

Here's how I measured. I took 1/3 octave warble tones every 1/3 octave (from the Stereophile test disc), made 320kbps MP3 files using LAME 3.97, played them from the T30 into my sound board, then recorded and analyzed the signal using Adobe Audition. I had the T30 in "normal" EQ mode - no equalizer, no SRS. It's never more than 1 dB from flat from 20 Hz to 20 kHz - and this includes the frequency rolloffs in the sound board itself.

Since my sound board rolls off 1-2 dB at 20 kHz and about 0.5 dB at 20 Hz, the rolloff you see at the frequency extremes is actually the sound board, not the source device. And most MP3 files (even at VBR V0) don't even encode 19-20 kHz. Thus the T30 actually has virtually perfect frequency response - well under 0.5 dB error throughout the entire usable range of high quality MP3 files.

To give you an idea how good this is, I graphed it next to my measurements of my Rotel RCD-1070 which is a good quality full size CD player with ruler flat frequency response. The T30 response is within 0.5 dB of the Rotel throughout the entire range - and it's not even playing the original signal, just an MP3 copy of it.

I think this is quite an amazing feat of engineering especially considering the size, power and cost constraints of the T30. This is definitely one of the most linear and best sounding MP3 players on the market.

See attachments. The first is uncorrected response which is affected by the sound board. The second is the actual response - corrected for the sound board.

[pringuet]

Well done MRC01.
Quite an interresting test you've done here and it comes along with the great piece news that our player is a great one. (Not that we didn't know that before some will say !)

Sounds like you have the required hardware, software and technical knowledge to help on the following topic.
Can the mini-USB on the T10 be used to play from?
Seasquash will be happy !

regards,
Phil

[Febs]

You might want to take a look at Rightmark Audio Analyzer: http://audio.rightmark.org/index_new.shtml

It's a lot easier than measuring all of those test tones separately.

[MRC01]

Thanks for the link - neat product.

[ShyAnne]

Excellent work MRC01, and thanks for generously sharing your results!

I have one of each, a T10 and T30, there's no sound difference between the two so imagine results would be the same for the T10 model. I have tested plenty (too many!) of currently retail marketed MP3 players, and can honestly say these two are the best sounding by far. Some claim the older IFP irivers got louder, but those are not currently retail (discontinued), and the T-series gets plenty loud enough for me.