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VentureCraft Go-Dap GD-04 for iPhone 4 - Page 2

post #16 of 161

i do wonder about the hires capability and whether it can be switched off, iphone isnt capable of playing hires without crack and i'm not sure even then if it upsamples. so i suggest you just keep the high spec model bit-perfect rather than upsample so the spec reads well. i would also rather spdif on coax than optical

post #17 of 161
Quote:
Originally Posted by zzffnn View Post

Very interested. Please advise me on the following questions:

1) Is this unit only for iPhone 4? Not for 3gs, 4th and 3rd Gen iPod Touch, and iPad?

2) Does the headphone output take the analog signal from the dac of Go-dap or from the dac of iPhone?

3) what are the dac chip and the opamps?

Thanks.



1) I am pretty sure this doesn't support the 3GS/3G (but afaik, they have made an earlier version for these iPhones)

2) Donno, but but would guess DAC of the iPhone

3) Donno either :P

 

 

post #18 of 161
I'm slightly confused. the iphone doest play anything above alac 44khz/8bit, so how is the go dap playing 48khz/16bit?
post #19 of 161

Thanks Jonasklam,

 

I should have specifically ask VentureCraft / Go-dap to answer my questions. We are speculating after all (I would guess the same as you said but that is just speculation). I think only VentureCraft / Go-dap can answer these questions. Thanks.
 

Quote:
Originally Posted by Jonasklam View Post





1) I am pretty sure this doesn't support the 3GS/3G (but afaik, they have made an earlier version for these iPhones)

2) Donno, but but would guess DAC of the iPhone

3) Donno either :P

 

 


Originally Posted by zzffnn View Post
 

Very interested. Please advise me on the following questions:

1) Is this unit only for iPhone 4? Not for 3gs, 4th and 3rd Gen iPod Touch, and iPad?

2) Does the headphone output take the analog signal from the dac of Go-dap or from the dac of iPhone?

3) what are the dac chip and the opamps?

Thanks.

 

 

 

post #20 of 161

 

Hi, everyone!

 

To answer your questions

 

1. Unit4.0 is only for iPhone4.

 

2. Unit4.0 receives digital signal from iPhone4 and convert the digital signal to the analog signal through the DAC (Analog-to-Digital Converter) loaded on the device, then outputs analog signals to a headphone/earphone by amplifying the signal with a headphone amp.

 

3. DAC Chip: AKM http://www.asahi-kasei.co.jp/akm/en/product/

    Ope-Amp: Burr-Brown http://www.burr-brown.com/

 

4. Unit4.0 decodes the digital data in several formats coming from iPhone4 into PCM format.

A sampling rate convertor loaded on Unit4.0 changes frequency response as all in 48kHz within the decoder then the DAC converts 48kHz/16bit into analog signals.

 

Thanks!

 

VentureCraft

 

post #21 of 161

erm DAPVenturecraft, i think you should realize that this forum is probably a bit more savvy than your average forum. telling us that the dac is made by akm and the opamp is made by burr brown/texas instruments, tells me nothing. both companies make nice sounding, appropriate products and stuff that sounds like utter poo.

 

when asked here what dac and opamp, its a specific question of what model dac chip and what model opamp. is the dac chip a ladder dac, sigma delta dac, 32 bit dac, upsampling or non oversampling. is the opamp a fet input opamp with unity gain buffer, or bipolar input opamp. is the digital transfer from iphone asynchronous or isochronous endpoint etc etc.

 

ok so thats probably a bit more technical than the average user here, but there will be some that want to know more and even those who dont really understand will want to know the details so they can go and get the research done so they do understand

post #22 of 161

You are a tough man, qusp. But that was exactly what I wanted to know.

 

Yes, specific dac / amp model please. Vendors here usually disclose those specs as selling points. If there is anything fancy inside, this forum is the place to reveal it.

 

edit for typos.

post #23 of 161

hehe wasnt meant to be harsh, just real feedback. I also didnt expect you to furnish me with answers to all those specs, although we both know quality sound is all in the implementation of the chips. the opamp model and dac chip assignment shouldnt give away anything of your design and even then depending on the implementation, that doesnt say much either. both companies have massive catalogues, thats all. its an intriguing product and i'll keep my eye on it for transport duties.

post #24 of 161
post #25 of 161

 

Go-Dap Unit4.0 Review by Stapa Saito. Only available in Japanese.
post #26 of 161
Thread Starter 
At least now we know what DAC and OPAMP the GD-04 is using.

DAC - AKM AK4353
OPAMP - JRC MUSES8820E

Hmm... the headphone out is also the optical output...
post #27 of 161

Is the Go-DAP 4.0 available in the US yet and if so what is the cost and how do we order? I was VERY VERY pleased with Go-DAP for my Iphone 3GS and now that I am ordering a 4S I would love to have some info on how to purchase one of these for the new phone. Thanks.

post #28 of 161

Did they mention the ETA for availability in the US before?

post #29 of 161

Hmmmm...I've had my Go-DAP for about 4 days now and when I bought it I had to sign a form to say I'm testing and have to provide feedback. Now that iOS5 is out (and I've heard problems of iOS5 with CLAS), I'm assuming the Go-DAP & HP-P1 will have the same problems. Chances are these will probably have to be fixed before going for an international release.

 

Go-DAP vs HP-P1

post #30 of 161


Is final design, or they will still change the prototype?

 

That volume knob seems to big in the pictures.

 

So far, how it compares against hp-p1?

Quote:
Originally Posted by AnakChan View Post

Hmmmm...I've had my Go-DAP for about 4 days now and when I bought it I had to sign a form to say I'm testing and have to provide feedback. Now that iOS5 is out (and I've heard problems of iOS5 with CLAS), I'm assuming the Go-DAP & HP-P1 will have the same problems. Chances are these will probably have to be fixed before going for an international release.

 

Go-DAP vs HP-P1



 

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