[aos]

I was experimenting with this EJ915 over the last few days, powered through AC adapter, connected to my new portable DAC with optical cable. It worked great. However, on Monday I wanted to listen to it in bed and I didn't have enough free outlets there so I used external battery pack. What I got are frequent and intermittent glitches in the right channel, that make any kind of listening impossible. When it starts up sound is fine, then after about 10 seconds it starts producing very loud clicking noises in more-less random intervals.

My guess is, it swithes on some kind of aggresive skip protection when it runs on batteries only and the quality of sound suffers. I cannot notice this if it's plugged in my home receiver through the same optical cable, or through the headphone out. Now, I'm going to try to see if I can do something to my DAC to fix this, but the fix would effectively just either mute signal or repeat the previous sample for the duration of glitch - which is what receiver and the CDP have to be doing as well. So far the diagnostics of digital receiver chip in the DAC definitely shows that at least some of those glithes cause it to go through the "clock transition" phase where it re-detects the incoming bitrate etc. Basically, when CDP is fooling around with reading from/to buffer, it occasionally drops samples. So I guess, whoever was saying that the G-protection (the highest level I guess) reduces the quality of sound, was right.

 

[pedxing]

I am glad I am not the only one with problems with the 915. My 915 line out sometimes producess scratchy noises and popping sounds. I also noticed that the output of distorts easily at moderate volume levels. I have lost one of the channels completely at random times too. Sometimes, it just completely gets lost and stops playing all together right in the middle of the CD. I encounter these failures more often with the AC adapter than I do with the battery pack. I guess I have the opposite problem in respect to the power source.

I never used the optical out, so I can't say that I have lost the right channel before with the optical out. I wonder if the optical output mode has no compression, but I do know that using the normal line out or the headphone out uses the 40 second compressed buffer (stop the CD from spinning after playing one minute of music and see how long the music continues to play for, but you need to hold the refrigerator door button down the entire time).

Basically, I gave up on the 915 and bought the 725. I am having much better luck with the 725's reliability, but the 725 sound quality has a funny treble. The treble rolls off quickly, but its abrasive compared to my Yamahava CDC-555 CD player.

 

[aos]

I just exchanged my 915 for 725 as well. When G-protection is on, I get the same glithes on right channel with optical out, HOWEVER, G-prot can be turned off on this one, and then even on batteries, the sound is fine. Yippee!

 

[Peddler]

I have the 915 and I think it's an outstanding player. I have used it straight with 888's and with 4P's with no problems. I have also used the line out with my Airhead and 4S and not noticed any of the problems that have been mentioned. I have made digital recordings from it using my mini disc recorder and the optical outputs without problems either.

I suspect that there's an issue with quality control with this player. I also have the Panasonic 570 and I have to say that generally I prefer the Sony - sound quality is perhaps very slightly better (certainly less line noise) and the anti-skip works a treat.

 

[aos]

>I suspect that there's an issue with quality control with this player.

That's quite possible. Mine had even trouble playing my test CDR, occasionally hanging and skipping to next track while in a middle of previous one (all that while sitting on the floor, not being shaken).

 

[Peddler]

By the look of it I was lucky. I honestly have to say that the 915 is the best CD player I have had so far. It makes an excellent portable unit thanks to its anti-skip and I think the sound quality is very very good.

By the look of it perhaps people have to be careful when considering purchasing one of these (especially second hand) but if you do get a functional unit, I'm sure no-one will be disappointed with it.

My 915 exhibits absolutely zero line noise, is neutral sounding and is an excellent tool for making digital MD recordings whilst roung at friends using MD. The unit absolutely doesn't skip (I've known MD players more prone to skipping than this) and the build quality is outstanding.

I must admit though at the moment i'm using the Iriver2 MP3/CD player for most silver disc listening - although from a sound quality perspective, it's definitely not as good as the Sony, the differences when used in conjunction with the Airhead and ER4S headphones is fairly marginal.

 

[thomas]

I have the D-ejo1, which appears to be based on the same circuity...

I don't think there is any compression in the antiskip, as the antiskip will last for about 15 seconds either when its running of AC or batteries... When running of AC, the motor is constantly spinning, and the buffer is always full. But when its running on batteries, it fills up the buffer, then stops the motor and reads off the buffer until its empty, then repeats the process.

Since there is no difference in antiskip times, compression is either always on or always off, and wouldn't account for dropped samples...

When the motor begins spinning, there is definatly an audiable burst of high-frequency noise in the analog outputs. I'm guessing that sony engineers had a hard time controlling this noise, and it radiates through both the digital and analog circuity. This could interfere with the digital signal enough to cause the problems....

Or, as you said, the buffer could be making glitches as it switches between disc/buffer, and dropping samples.

 

[Ctn]

just curious, does this happen with the 925 as well?

sometimes i get dropped samples when im on the move with the 10sec mem

 

[aos]

There's definitely dropped samples with G-prot on, as the PLL in digital receiver chip is loosing lock. I don't think there's any compression, likely just that as Thomas said motor spinning is causing trouble and the poor thing drops the signal for a moment. Either this new Burr-Brown chip I use is very sensitive to it or there is a problem in the way my DAC handles it (it makes no sense to happen only in the right channel). At any rate, it happens even with G-prot off but only once, about 10-15 seconds after you press play and sometimes when the track is changed. My problem is solved anyhow, thank God.

 

[Joe Bloggs]

Solved how?

 

[aos]

By buying 725 and turning off G-protection

.

 

[Ctn]

so what's happening with the other pcdp

*hint hint*

 

[Joe Bloggs]

Don't you already have the 925?

 

[Ctn]

yeah i do

just curious

 

[aos]

Other CDP (915) went back to the store. It was cheap (open box) but so many things were missing that it was actually overpriced. Anyway, I had good luck exchanging it for 725, which is bulkier and heavier but it'll do.