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carlie7

Sharp 4-pole headphone connector question

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Hey All,

I just ordered a Sharp IM-DR80 from Minidisc Access. It state that it has a 4-pole headphone connector. Do I have to use the 4-pole connector only or will the usual 3-pole also work... I'm hoping yes since 4-pole arephones are pretty hard to come by.

By the way, Minidisc Access is a great company to do biz with.

Thanks.

Carlie

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You ABSOLUTELY MUST use 4-pole headphones with a 4-pole amplifier. Negative signals in the 4-pole system differ between channels, so merging them in a 3-pole headphone connector will distort the sound, and may even lead to amplifier damage.

But it is possible to buy a spare 4-pole mini-jack connector (say, for a camcorder, or a video portable), and solder it to a set of standard headphones, making sure that EACH POLE HAS ITS OWN WIRE.

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Thanks for the info. Guess I'll be sending it back unopened. Too bad. Looks like a great unit.

I'm using my MD-DS70 with normal headphones without problems.

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Uh-Oh... conflicting reports. Does anyone know for sure? I read the manual for the DR80 and it doesn't say that you can't use the 3-pole phones with it... but then again it doesn't say you can either.

Sinus, how long have you had/have you been using your DS70 with the 3-pole phones?

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Uh-Oh... conflicting reports. Does anyone know for sure? I read the manual for the DR80 and it doesn't say that you can't use the 3-pole phones with it... but then again it doesn't say you can either.

Sinus, how long have you had/have you been using your DS70 with the 3-pole phones?

2-3 months. the manual says something about "even better sound" when using 4-pole adapter or remote but not something dramatic like "you'll fry your unit if you not use four-pole components". I'd like to hear further comments from Avrin as he is a very competent person.

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4-pole amplifiers are designed as a relatively cheap way to achieve high output power at low supply voltage.

In traditional 3-pole amplifiers, there are three wires - one common, which carries no signal, and two channel wires carrying left and right channel signals, which, after driving the headphones, are fed to the common wire, thus closing the circuit. Since the headphones have a non-zero impedance (16 Ohms or higher), the system works as expected, playing music with no chance of overload.

In 4-pole systems, on the other hand, each wire carries a signal. Wires for a single channel actually carry the same signal, but with reversed polarity (it is this technology that allows increasing the output power, since a double amplitude arrives to the headphones). Now consider a situation, when you have a pure sinewave playing in the left channel, with silence in the right. If you shorten the negative signals of the two channels, connecting them to the common wire of 3-pole headphones, and feed the positive signals to the left and right channel wires, you won't get the original sinewave in the left channel and silence in the right. The left channel will play the sinewave at a seriously reduced amplitude, while the right channel will also play it at some level (the level depends on the impedances of the amplifier and the headphones). Thus, the original signal and its stereo separation will be seriously distorted. And short-circuiting the negative sinewave from the negative left channel wire to the zero in the negative right channel wire may lead to amplifier damage.

The above situation may seem theoretical, but signals of actual music may become even more distorted, depending on what you have in two channels. And a good bass drum at a high volume level may fry the amplifier even faster.

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The Sharp is a 1-bit player correct? It is supposed to give a better sound through the output. Maybe in order to experience proper 1-bit audio you must therefore use 4-pole headphones. Otherwise using standard headphones you would lose on sound quality. It's worth investigating further but if Avrin is right then it's a more serious issue and I'm surprised there would be no mention of it in the manual.

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I have bought a Sharp ad-D1AC for the use on my DR77. To be honest I can´t hear any big difference in sound without using it. If you want to be on safe side you can still get these 4 to 3 pole adapters at Bluetin.com (Japan section/ accessories).

op-add1ac.gif

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I own the DR7, DR80 and DS77 and have never noticed any difference in using the 4 to 3 pole adaptor with any headphones. I remember when I got my first unit wondering what the heck the adapter was for.

However, in my opinion the sound greatly benefits from these Auvi units when you use 4 pole headphones. The sound is rather ordinary and inferior to the Sony units with the other phones I have.

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So, what it sounds like to me is that I can use 3-pole phones without damaging the unit. All that will happen is I will be sacrificing sound quality. Is that a safe assessment?

Edited by carlie7

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I understand I can buy an adapter, what I am curious about is where can I buy 4 pole headphones that wouldn't need an adapter. I see culp4684 has some Sharp earbuds listed in his equipment that are 4 pole. Does any company make 4 pole over the ear headphones?

AS to adapters, is this likely to work

http://www.radioshack.com/product/index.js...oductId=2603246

The reason I am curious is I bought a Sharp IM-DR420H which did not come with the adapter.

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I understand I can buy an adapter, what I am curious about is where can I buy 4 pole headphones that wouldn't need an adapter. I see culp4684 has some Sharp earbuds listed in his equipment that are 4 pole. Does any company make 4 pole over the ear headphones?

Sadly, the Sharp HP-MD33's are no longer made and nearly impossible to find. There have been variants, but none have the four pole design. Other than the ones furnished when you purchased a new unit, there was one other Sharp model offered at Audiocubes years back, but I can't remember the model # or even what it looked like.

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I understand I can buy an adapter...

sorry, I´ve overlooked "headphones"... :rolleyes:

What about those low budget 1-Bit units? Were they equipped with 4 pole phones? They usually sell for little money on ebay.

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What about those low budget 1-Bit units? Were they equipped with 4 pole phones? They usually sell for little money on ebay.

Yes they do, at least the IM-DR400 snd 420 did. I was never knocked out by the 1-bit sound, maybe just on these machines, but always preferred the Sony sound signature to all my Sharps. BTW, I've still got a 4-3 pole adapter if anyone's interested...

Edited by Barock

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All portables (and most "stationary" units now) have 1-bit DACs. Which does not improve sound quality in any way, when compared to a good-old 16-bit DAC that is much more expensive to manufacture because of the need to have an array of 65536 very high-precision resistors for each channel.

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Well, I did it. The Sharp IM-DR80 came in the mail today and after I charged it I plugged in my 3-pole phones and guess what?... it sounds fantastic! The unit isn't getting hot or malfunctioning in any way. So I guess using the 3-pole phones is pretty harmless... at least for now. I'll continue to use it a lot throughout this week and I'll let you all know if anything changes.

Not surprising, the 3-pole Koss KS-35's that I'm using sound better than the 4-pole phones that can with the unit.

All in all its a pretty slick little machine.

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All portables (and most "stationary" units now) have 1-bit DACs. Which does not improve sound quality in any way, when compared to a good-old 16-bit DAC that is much more expensive to manufacture because of the need to have an array of 65536 very high-precision resistors for each channel.

I always wondered about this, Avrin. Can you give us a list of the last equipment of each type made by Sony that uses 16-bit DACs? I would be very interested to review in the light of this comment of yours.

Stephen

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The Sharp has a real nice, warm sound. Smooth base (set to Bass 2) and spacious highs/treble. Still using the 3-pole Koss KS-35's and no problem yet.

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I always wondered about this, Avrin. Can you give us a list of the last equipment of each type made by Sony that uses 16-bit DACs? I would be very interested to review in the light of this comment of yours.

Stephen

I have no idea about what equipment actually uses 16-bit DACs nowadays. Probably, more expensive units ($1500 and above) do.

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OK. My JE640 uses a chip (IC500 in the service manual) called AK4524-TP (Sony part # 875958426), for both D->A and A->D, I think. But I have no idea where to find the specs of that part.

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Hello, I have several MD Sharp models. I have compared the Sharp Md-St770 which sounds correctly with a 3-pole headphone, but when tested with this same headphone on the Sharp Auvi Md-ds8 / Md-ds30 (1bit), the sound quality decreases mostly in detail Musical and diminishes the power of sound, I'm talking about a AUDIOTECHNICA ATH-MX50. In conclusion would be recommended the 4 pole plug. Now, there is no warning to spoil the machine or in any case the amplifier. Is there news or recorded reports ?. I think that the sound quality is reduced because the sound through an Auvi with 3 poles is very poor. In any case, confirm if there is really a risk of damaging Sharp md by the use of these 3 pole plug, in Auvi machines. Thank you. 

 

Hola, tengo varios modelos MD Sharp. He comparado el Sharp Md-St770 el cual suena correctamente con un audifono de 3 polos, pero al probarlo con este mismo audifono en el Sharp Auvi Md-ds8/Md-ds30 (1bit), la calidad del sonido disminuye sobre todo en el detalle musical y disminuye la potencia del sonido, estoy hablando de un audifono AUDIOTECHNICA ATH-MX50. En conclusion seria recomendable los 4 polos plug.

Ahora, no hay advertencia alguna de estropear la maquina o en todo caso el amplificador. Hay noticias o reportes registrados?.

Creo yo que la calidad de sonido si es mermada pues el sonido a traves de un Auvi con 3 polos es muy pobre.

En todo caso, confirmen si realmente hay riesgo de dañar el md Sharp por el uso de estos 3 polos plug, en maquinas Auvi.

 

Gracias.

 

 

 

 

 

 


 

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