wow lots of stuff to answer here, sorry for the long post, but seems there is some confusion in the ranks
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It really isn't about ruggedness ... they are paired, and essentially useless without one another so unpairing them seems like a rare event anyways. its about data transmission and cleanliness. it looks like a clusterf*, when while your deprecating the old connection essentially due to the pairing, you're free to move forward in design and tech for connecting the IEM. the old design would seem like the new bottleneck. i just think its forcing the old pin arrangement in the new reference which clearly has higher demands as far as channel separation from the adaptation of the old 2 pin to the new 2x2pin *(which is garish), square peg/round hold. i would go for a single ended high bit rate (hbr) multichannel (up to 4 triad pair channels in some cases; 4x(3 pins; 2 channels - 1 ground)) connector that is small enough for the IEMs ... just my observation, if i could ask jerry i would: pm his email if you guys have it.
I think you have missed the vital DAC with digital XO stage, before you start trying to tell them what to do, maybe read up a bit, because I really dont think you understand the concepts at play here. I agree there could be a better connector, but bitrate waah?? the wires used already will take any 'bitrate' you throw at them. adding more wires will not make any difference at all and optical is plain weird I dont know what you mean. the dac is in the dac/amp, not in the IEM, the crossover is digital too, thats the whole point of this was to take it OUT of the IEM to somewhere that could do the required processing and have enough room and power to do so in a sophisticated way; that requires a combination of hardware AND software.
besides, optical cables would be microphonic as hell
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I talked to Matt while evaluating the Solo prototype. He decided by the Woolfson DAC because it is more advanced than the version installed in the iMods, yet the power requirements are still within the limits of the 5V USB-out of the iDevices. This revelation had dawned on me after a totally separate 1-on-1 I had with Fang about his HFM-801 design decisions. Fang very patiently and clearly explained that high-end DAC chipsets (no doubt DSPs as well) have much higher power requirements than low- or mid-grade 16/44 implementations. Now there are still differences even with those, because a quality 16/44 chipset with an accurate clock and low jitter parameters will sound noticeably better than without. Bottom line is that the Solo is using the best DAC chipset available today that can be powered from an iDevice dock on-the-go.
well actually the sabre is 3v3 volts, but around 200-250ma which could be a problem. I mentioned the wolfston, because its a dac that is not being used in the way we would connect it here. does the solo really take its power from the idevice/usb host?? wow that would chew battery
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Jerry just let me know that the final build WILL ACCEPT 16/44 audio from the mini USB.
I'm not certain what his actual intentions are in this regard, but he also said that taking 24/192 from the USB input would add $250-300 to the cost of the device and take about 6 months to become available.
well there are some new native usb 2.0 audio chips that will do it that are available now at digikey, but yeah development would take a little while, the PCM270X reciever he is probably using is OK, but jitter can be a bit of an issue. I wonder if they could do any ASRC to upsample/resample it. I agree though that going hirez usb would take time and money to develope and would also add a higher power overhead; which is most likely already stressed with a multichannel dac/amp in a portable
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... whats the rush? fix the output connector to something optical, ive checked out some AOC cables and they are small enough to keep the signal digital all the way through to the BA's with clear channel separation on a SINGLE ended termination point on the IEMs themselves. why skimp on the connector. it doesnt need to be standard, just available. it already costs $1750 ... whats an extra $250 and superior SQ through a usb port?
@thread can you please PM Jerry's email information (thanks) i would like to email him about the engineering aspects of this amp. they said they were open to see what people were looking for. i would like to see what he thinks.
thanks
USELESS INFO BELOW:
something that has _NOTHING_ to do with ANYTHING on this site: i was just finished with this post and looked over at the juice bottle on my desk its Simply Limeade which is produced in Apopka Florida ... LOL.
I would think before doing that, send him emails with this jibberish and he wont know what to say
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So if I understand it right, the [size=medium][size=medium][size=medium]AlgoRhythm Solo extracts digital audio from an iPod and also has a dac on board, next to a digal output for the JH-3a.[/size][/size][/size]
Does it extract high-res also, and if so how does one get high-res audio into an iPod?
none of the old range of ipods support hirez files, the codec they use downsamples to 16/44 even when you can actually play them (hirez flac with rockbox) the iphone G4 apparently supports WAV, ALAX and AIFF, I suppose there is a possibility it will do hidef, it has hidef digi camera, and I would bet the processor used will support hires audio, maybe even multichannel....
that sucks
so its about the cable makers, not eliminating one of the last minute bottlenecks? what happens when they design a custom connector and R&D is finished ... JH-6A? if hes trying to innovate, then put it out there, so far out that other companies cant adapt fast enough, to keep up with the 6-8-12 month cycle JHA has been churning. id go optical with an hbr AOC chip in the the connector.wire and that chip will convert the optical electrical signal into an electrical signal for the BAs in the IEM ... but thats just me. why leave it for the next amp, design it right the first time. squeeze it out! it simplifies the connection to the IEM that way you can clean up that 2x2 structure that they are using now.
huh the cable makers haha not me
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it isnt more conversions, no need to convert the signal to analog from the amp itself to the cable to begin with. the signal conversion (optical electrical to electrical) is taken care of in the connector (a special AOC chip is necessary, which is similar in size to an XLR connector) which is powered by the amp. no need for a chip in the earpiece (which is what precipitated the new amp in the first place). also the connector wouldnt take up more space than the 2x2 they have in place. your also not limited to 4 channels with one ground per ear ... you could have also send the signal balanced to each driver if you wanted with a high enough bandwidth. i would surmise that a digital file at 24/192 would benefit from that.
ps: can the iphone4 play back 24.192 aac, flac, or alac (if apple even sells music with such a BR)?
I say go out there and make it yourself man; you go boy!! some could say the same about me I guess, but I wouldnt even pretend to have the knowledge and knowhow to do what matt has done here, even if I feel there were a few things that could have been done differently, I still think this thing is way cool as is.
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Current laptops don't support 3.0, except for the new ones. 2.0 definitely can't support the massive bit rate of HD music files. Anyone thinking of going out to buy a brand new laptop just to listen to their audiophile setup in HD? Yes, I know some of you have plenty of extra cash lying around, but I'm speaking to the majority. Is there a real purpose to a usb>spdif converter other than to eliminate jitter (I'm assuming that's one of its functions) and expanding compatibility with a spdif-only DAC? Converting usb 2.0 to spdif doesn't change the fact that the usb 2.0 circuitry on the motherboard can't handle the high bit rate (EDIT: on second thought, maybe it can).
(2nd EDIT: Okay, it definitely can. I just found products that can convert to spdif up to 24bit/92kHz. One thing I'm curious of is does the computer still automatically bypasses the onboard sound circuitry to the external DAC if there's a usb/spdif converter + spdif cable in between? I'm guessing not, because such spdif-input-only DACs don't have the firmware for usb plug-and-play. In which case, how would you configure the operating system to bypass the onboard sound and send signals to the usb port?)
hehehe USB2 handles 400mbit; hidef audio wouldnt even take up 2% of the bandwidth and there is already a native, driverless hidef USB 2.0 audio codec running on mac, though not PC yet. The only hidef USB on PC is proprietary like the hiface which needs a driver, which wont be supported on ipad, but i'm hoping they port the USB audio codec over to ipad/iphone 4.
yes it does bypass the audio hardware, its only sending data, which is buffered and then converted, then reclocked in some cases.
sorry I dont know what you are on about in the last bit, dacs do indeed often have what is called a USB receiver, which does a similar job to the convertors you found, but internally in the dac and the conversion is most often to i2s rather than spdif; so the audio is just sent as data, which is buffered in the reciever, then with good devices the clock component is thrown away and a new low jitter clock generated and passed on along with the music data to the DAC. in the case of the convertor you mention, the dac just needs to accept spdif or AES, be it optical, coax (RCA or BNC generally, but like this and some laptops a 2 terminal mini can be used)
to sum it up, the bandwidth with usb was never the problem, USB 1 has enough bandwidth, the problem has been a lack of software and USB receivers that could decode the audio data in hidef. hasnt been really implemented until fairly recently, but there has been a spate of new devices come to market in the last 6 months and more even recently like the native driverless USB 2.0 audio codec