Jump to content

kdoot

Members
  • Content Count

    2,349
  • Joined

  • Last visited

  • Days Won

    2

kdoot last won the day on March 29 2014

kdoot had the most liked content!

Community Reputation

452 Excellent

3 Followers

About kdoot

  • Rank
    Digital devotee

Profile Fields

  • Location
    Queensland
  • Country
    Australia

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. What's the objection to using a transformer? Our entire AC power infrastructure is based on transformers stepping down from 250kV to a nominal 230V. Electrically speaking there's absolutely nothing wrong with adding another step to 110V, regardless of how expensive are the items you'll be powering. OT... my first ever pre-amp is the one I bought from the classifieds here:
  2. Great write-up, thanks heaps. What’s the maximum rate supported by the Pi in this configuration? I’m currently limited to 192kHz PCM or DoP64 in my setup and accessing the higher speeds would be the main reason I’d consider switching to an I2S input.
  3. New set of balanced interconnects now linking the EC4.7 to my power amp. Holy wow this sounds beautiful.
  4. And it turns out... that’s because I only knew half the story! I got some foundational RF training as part of a Wi-Fi course and they never mentioned that their definition of decibel only applies to power, not to amplitude. You are correct. Thanks for prompting me to dig deeper. Wish I liked logarithms more.
  5. That gain is not unusually large. Each 10dB is 10x, so 100x is only 20dB and 1000x is 30dB. Most solid state power amps are in the mid to high 20’s and some crack 30dB of gain. What is very different though is the sensitivity. As you say, peaks on the order of 1mV instead of the hundreds or even thousands of mV that a power amp is designed to handle on its inputs.
  6. I only have the one EC item, but I have zero options about where to put it:
  7. So what are you using today, FP? I looked through your post history but couldn’t find the answer to that. Why did you sell the 4.7?
  8. Well I took a punt yesterday and based on nothing but specs and sparse reviews became at least the fourth owner of EC 4.7 pre-amp serial 100583. It’s my first Electrocompaniet experience and in fact my first ever pre-amplifier, having lived the “best pre is no pre” lifestyle for close to ten years with DACs directly into power amps, and integrated amps prior to that. 24 hours in, I’m loving it – even though I don’t yet have a second set of balanced interconnects to go from the pre to my power amp. There’s just more music here now, more depth in soundstage, more movement of the air in the room, like my 8” woofers just became a few inches bigger or something. I’ve lost a bit of resolution, detail and top end, but I expect to get at least some of that back when the second set of balanced cables are in place. Will let it settle in for a couple of weeks and then do some more focused comparisons. I didn’t “choose” Electrocompaniet. It’s just the first pre-amp I came across after ages and ages of searching that was fully balanced, fully solid state, with better input and output impedance matching than my DAC-to-power-amp connection, of sufficient reputation for audio quality and at a price I was willing to experiment with. Interestingly, some of those criteria would actually rule out the 4.8 and the 4.5. If only the frickin front fascia was 1mm narrower so it would fit into my cabinet. Ah well, can’t have everything! 😆
  9. I’ll bite. PM incoming with request for contact details.
  10. O2so what is the DAC you would like to be using? Your NuWave Phono Converter is a gem of a thing. Doing room correction in digital domain prior to DAC is a great approach. Finding the right DAC is your main challenge now, but USB input is not going to work out well with the other gear you currently have.
  11. USB DACs *always* require a data stream from a computer of some sort. It can be a very small computer, but regardless that's what's required. The device you linked to would probably be able to do the job, but the chain would be: SPDIF source (determines the overall clock rate) PreSonus (SPDIF in, USB out) Computer (USB in, USB out using isochronous mode) DAC (USB in) It's expensive and complicated, and because of the isochronous USB it'd probably sound pretty ordinary. I tried to find another device on the market that could replace that PreSonus box at a lower price... and couldn't!
  12. One of my all-time favourite digital audio devices is the Audiophilleo. It's a USB to SPDIF converter. I understand its theory and operation very intimately, and it's extremely similar in principle to many other devices on the market which as you say range from very cheap to quite an investment. The thing is, they're the exact opposite of what the original poster is asking for: they let you get audio out of a computer using USB and feed it to a DAC that only has a SPDIF input. The reverse process technically can be done, but it's full of serious challenges and compromises some of which I outlined in my previous comment.
  13. Let me just explain the issue a little bit. USB supports two-way communication but is a master/slave arrangement where everything is coordinated by the "host". A USB-only DAC is not a host, it is a "device" which needs a host to send it audio data. So your hypothetical converter needs to have at least the smarts of something like a Raspberry Pi or other small computer in it to play the role of USB host. SPDIF is a one-way communication. A SPDIF receiver watches the voltage switching between two levels and its first job is to try and "tune in" to the transmission frequency. Just about everybody supports 44.1kHz (I recall a Bel Canto CD player that would only output at 96kHz, after doing some sample rate conversion) but no two clocks run at exactly the same rate so the receiver has to adjust itself, usually with a PLL, to track the overall average rate of the incoming data. Major point: SPDIF runs at its own rate. We learned early on in computer-based hifi that there are two modes of operation for USB Audio and one of them sounds *bad*. It comes down to clocking: if the audio device (the DAC) is in control of the flow of data, using its own local clock and a USB mode called "asynchronous", then you could get good results. If the host is in control of the flow with a USB mode called "isochronous", you could not. So the problem with this converter idea is that you can't simultaneously have the DAC in control of the flow of data via USB asynchronous mode while the USB host is receiving that data from a SPDIF source that runs at its own rate. The USB system would have to operate in isochronous mode, which is how you get the worst kind of digital sound.
  14. Nah that one won't do what the original question asked. It'll let you take a SPDIF input into a computer. It won't sit and relay audio data from SPDIF to a USB DAC.
  15. Which boards? Does the USB output operate only in isochronous mode or is there some kind of ASRC going?
×
×
  • Create New...