[greenhorn]

AFAIK, these 3 models are identical, the only difference being that DD470 sells without the cradle.
----------------------------


Now the question.

The User Manual (http://www.minidisc.org/manuals/sharp/sharp_mddr470.pdf), at page 2, reads: "Sharp has adopted 4-pole plug headphones and a remote control that completely separate R and L sound. Enjoy the high quality sound of the Mobile 1-bit digital amplifier". There is also a pic of the plug with 4 contacts, instead of 3.

Then at page 58 ("Listening through another system") the manual recommends using a "conversion cable 4-pole to 3-pole plug conversion). Basically a cable with a 4 contact mini plug at one end and a 3 contact (normal) mini output at the other.

My question is: what actually serves this conversion cable for?Inside the 4 contacts mini output (to be found on the MD itself or on its remote control) the two L and R ground contacts will be, anyway, simultaneously touched by the common ground contact of a regular (3 contacts) minijack. So why use the conversion cable?

... as a subsidiary question: is it true that separating the ground for L and R channels improves the sound?

 

[tbdoah]

I've never noticed the difference on any Sharp (incl. the DR7), as all Sharps have 4 Pole plugs

.

I really don't see the reason for a 4->3 converter cable, but I definately sure that Sharp made it for no reason at all. There must be some reason behind it.

 

[greenhorn]

Quote:

Originally posted by tbdoah I really don't see the reason for a 4->3 converter cable, but I definately sure that Sharp made it for no reason at all. There must be some reason behind it.

Yes, I am curious too! I am more than willing to find out which this reason is!

 

[DigDub]

the 4 pole to 3 pole adapter is for cassette adapters, in case you need to use the car cassette player. sort of like a line out.

 

[akio]

all incorrect. the 3 to 4 pole adapter takes advantage of the entire "1bit" feature. 1bit is how it gets good battery life - it alternates - + - + along the adapter, hence the 4 poles, one for each. this allows the amp to alternate the current, which i understand is much more efficient. 3 pole headphones will still work, but supposedly aren't as loud at equal volumes. the adapter has also been said to muddy up the sound a little - this is the only reason i havent bought the DR7 yet. the DR7 is a 8mW/channel device, and the supposed reason for lack of volume with a 3 pole plug is that it knocks the output to 2mW/channel. Just hearsay, but its been enough to keep me from ordering the doc before i can afford a mint etc. hope this helps - check out the forums at minidisct.com for more in depth info.

btw - the DR7 comes with MX400's which are good in their own right, and many say that they are the best sounding headphone for the DR7.

 

[ProFingerSk8er]

mx400 dr7 came with are the best sounding phones with DR7?

u sure about that? i would thinkg 4 pole phones would make a difference. but that BIG of a difference

 

[akio]

i think its a volume related issue - the 4 pole mx400 at 15/30 clicks are the same volume as the regular mx400 at 27/30 clicks. Even if it sounds the same, mentally i like listening in the middle

 

[DLP]

The MX400 that are supplied are the best because of the 4 pole I assume is the assumption. They aren't taking into account the clip ons that come with the DR480 or the 4-pole ear buds Sharp has released, currently available at Audiocubes.

Akio, hearsay is I'd say all it is. My DR7 powers my Sharp HD590s (easy to drive, but not that easy) as well as my MT180 (10mW per channel, non Auvi). The comfortable volume is about the same on both (about 16). The problem is people are getting confused over the math, because according to poorly translated Japanese documents on Auvi, the Auvi amp allows for 4 times the power with the right equipment connected. Unfortunately, it's never been really proven, and no one seems to be certain whether that means 8mW is with a 4 pole connection, or 8mW is the standard and 32mW is the 4 pole connection. Either way you slice it though, I think it just makes the technology look worse. Either you use regular headphones and lose any benefit, or you use their headphones and get a ridiculous amount of power (for an MD unit) that you'll never hear the benefit of (headphones that need that power), both are nonsense. Too bad their conversion cable is pretty crappy, I'd love to see if my DR7 put out the same power as an iPod

 

[greenhorn]

Do I understand corrctly? Using the cable "4 pole -> 3 pole" (that is, inserting it between the MD unit itself and the 3 pole headphones) would increase the volume and / or increase the battery life?

 

[RRX]

For me I don't hear any difference between the loudness of using regular 3 pole head phones versus the 4 pole ones when I plug the 3 poles directly into the unit.

I'm not sure if you all are comparing the loudness when using the 3 pole adapter, because using the adapter does seem to make the volume softer.

The adapter does also make my 3 poles (BTW, I use Aiwa hp-v161) sound crappy. Some when i use the adapter the sound gets very hollow, kinda like the live mode that Panasonic PCDP have.

Does anyone else experience something similar?

I also don't really like the sounds of the supplied earbuds. Are they REALLY the MX400? I prefer the sounds of my Aiwas over them. The highs on the supplied earbuds seem to suffer from a bit of splittiness the bass is not as strong as my Aiwa. I'm not sure if I've burned them in enough yet but they don't sound as good as people say they do.

 

[greenhorn]

Quote:

Originally posted by RRX when i use the adapter the sound gets very hollow

Yes, the same happens to me when I insert the adaptor between the remote and the headphones. The sound gets hollow, the bass almost disappears - and the volume decreases.

Maybe the adaptor is to be used "only" when connecting the MD to an amp

 

[davei]

A good 4/3 explanation is here:

http://www.minidisc.org/classd_amp.html

In short it's a phasing issue wtih 3 pole headphones.

 

[swalker]

Quote:

the DR7 comes with MX400's ...

There have been some debates over this issue as Sharp bundles share the same casing but it's been said these aren't identical to the MX400 inside. I had MX300 recently for a while and the Sharp bundles sound different from MX300 although they do show some similarity.

On the good side Sharp bundles project a very wide sound (wider than any earphones I know of) but splitty treble is fatiguing. At the end of the day, I preferred E888 and ER4 out of Sharp MD's over the bundled 4 polar earphones.