tda

So, as I understand, nobody is willing to help... Pity...

I just thought: what is it Sony changes that US and Europe units' HP output power differs more than 3 times (5 mW vs 1.5 mW)? It has to be something else than the mentioned resistors, because they are only 6 Ohms... I found this in the specifications for D-NE800: Output (at 4.5 V input level) ... Headphones (stereo minijack) Approx. 5 mW + Approx. 5 mW at 16 Ohm (Approx. 1.5 mW + Approx. 1.5 mW at 16 Ohm)* * For the customers in Europe I figured that to get a 1.5 mW instead of 5 mW output power @ 16 Ohms, you have to use at least 37 Ohm resistors ... or am I wrong? Any ideas on this? Of course, a service manual should resolve the issue tda

Actually have a pair of Sony MDR-ED31 headphones with a 16 Ohm / HP impedance, 108 dB / mW. So I think I raised the power by about a third of what I had (had: 16 + 6 Ohm, 1.5 mW, now: 16 Ohm, ~ 2 mW). Just a question: are there any GOOD HPs anyone would recommend? I mean lower impedance or higher sensitivity? Another interesting thing... When I listen to a recording without any EQ, I think I have full output power, but when I set the EQ to another preset (i.e. ambient, soft, hard, custom), it seems like something is cutting down even more power. Any ideas on that? tda

I finally decided to take my Walkman apart. An guess what I found? The HP amp is a AN17020B - which is a totally unknown type and even has a different package (16-SOP) type than AN17020A-VB (16-Quad)... I found the Right and Left channel outputs using the MZ-N10 service manual and was surprised to find that the resistors connected in series with the headphones (the ones which are usually used to cut down output power) are only 6 Ohm! This was quite disappointing, because I suspected much higher values, which would mean a bigger cut-off in power. As I already mentioned, the output power on D-NE800 is 1.5 mW for Eruope. I shorted those two 6 Ohm resisors, so now I suppose I have around 2 mW of output power, which is still too low. IMHO they changed the 5 mW / channel amp (AN17020A-VB) to a lighter 1.5 mW / chanel version Anyways, the request for a adequate service manual still remains open... tda

Hello all, Recently I bought a Sony D-NE800 CD/MP3/Atrac3Plus Walkman. I know, I know it isn't related to MD, but still may be interesting... The player performs OK, but (as you probably already know) it has a crippled low-power output on the headphone line. It is now ! 1.5 mW + 1.5 mW ! for Europe, whereas everyone else enjoys a normal 5 mW + 5 mW output. I studied the topic and taking in consideration that probably Sony doesn't use completely different technology in MD and CD players, decided to take my device apart and see what I can do. Of course it is quite painful to lose your warranty right after you bought it, but if you do it carefully nobody will ever even notice So, I discovered that indeed, the D-NE800 output is a Headphone Amp (17020B - of which I found nothing in the Inet) used priorly by Sony in the MZ-N10. I saw earlier complains about Sony's European crippling strategy and decided to hack the unit to a normal one. As I understood from previous posts, the hack is based upon the short-circuiting a pair of resistors which are 'killing' the power. There would be no problem for me to find them on a MZ-N10 device (with the service manual at hand), but having absolutely no info about D-NE800 makes it a little bit of a problem... So, if anyone knows anything about the HP Amp chip (probably AN17020B or AN17020A) or has any technical info on the D-NE800 (a service manual would be very nice), I would be glad to hear from you.