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JDS Labs Element IV DAC & HP Amp with EQ Review

Rate this DAC & HP Amp

  • 1. Poor (headless panther)

    Votes: 3 1.3%
  • 2. Not terrible (postman panther)

    Votes: 14 6.1%
  • 3. Fine (happy panther)

    Votes: 62 27.1%
  • 4. Great (golfing panther)

    Votes: 150 65.5%

  • Total voters
    229
Is an internet connection (plus up and running JDS servers and a connected computer of some sort) required for configuring the PEQ?
Yes, it is required at the moment. They are debating with themselves and asking for feedback from customers about creating a separate app for PC as well as Android/iOS. As a guarantee for customers, they promise to host open source code that can be compiled and run on a PC without an Internet connection, in case they decide to abandon the web app server.
 
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Me: Like, where?
* looks again *


Oohhh so this isn't a button?! :D
 
I don't understand how this PEQ works. So you connect to a server via a web browser, but how do you adjust the sound in the DAC itself?
 
USB isolator which it calls Synapse. Inserting that in the USB path eliminated all noise
Can you please make a separate review for that isolator? It might be the first USB accessory that actually works
 
Can you please make a separate review for that isolator? It might be the first USB accessory that actually works
Yes, I plan to do that. I also have another one from a different company so may compare them as well.
 
I don't understand how this PEQ works. So you connect to a server via a web browser, but how do you adjust the sound in the DAC itself?
Everything you adjust *is* in the DAC. The interface is on a computer/portable device but all settings take effect in the DAC itself.
 
Everything you adjust *is* in the DAC. The interface is on a computer/portable device but all settings take effect in the DAC itself.
So the computer/laptop communicates in parallel with a web server and the DAC itself?
Hmm... then it would not be very hard to convert it to a local web-app to make it independent of a internet connection, I think.
 
But in this product I am not satisfied primarily with the design. A large knob on top, a wall wart power adapter - not the style I like. Even cheap foreign companies now make more stylish and attractive devices.
I don´t agree. I think it is the coolest looking DAC/headphone amp on the market. I am almost tempted to buy it just for the looks of it (I will not, I already have a headphone amp with features no other headphone amp has, and I will never replace it if it not fail)

Is it not nice to have found a feature where subjective opinions are 100 percent legitimate?
 
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For anyone confused about why you can't just adjust the PEQ directly on the device (and I hope this doesn't come across as man-splaining):

The DSP in the Element IV implements the PEQ using filters, most likely bi-quad IIR filters. Those filters require specific coefficients to implement a particular PEQ "setting." Determining a set of IIR coefficients to correspond to a specific freq/amplitude/Q for one band of parametric equalization requires modest computational effort; trivial for a modern PC (or server) but far more than the presumably tiny microcontroller in the Element IV. Its a one-time task for one PEQ setting, not a realtime/ongoing process.

So you tell a server (through your PC browser) what sort of PEQ you want, and the server app does the math to determine the correspnding IIR coefficients, and those coefficients are passed back thru your PC to the Element IV, where the DSP runs the filters.

Not to mention the user interface aspect, where the PC can provide a rich visual interface to arrange your settings. Even if the processor resources were there on the Element IV, the diminutive size, dearth of buttons/knobs and tiny screen would make for a tedious effort to enter PEQ parameters.
 
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So you tell a server (through your PC browser) what sort of PEQ you want, and the server app does the math to determine the correspnding IIR coefficients, and those coefficients are passed back thru your PC to the Element IV, where the DSP runs the filters.
As I understand it, you can only load one setting at a time. If you want to switch between different headphones with different settings, then as I understand it, you have to open the computer and load a new setting every time? Is it possible to load the settings locally on a computer as files, or must the user connect to their server and regenerate the same settings over and over again if you want to switch between different settings?
 
tiny microcontroller in the Element IV
From the photos of the PCB, there is no dedicated DSP at all, so the filters are apparently implemented in the XMOS chip's engine.

So you tell a server (through your PC browser) what sort of PEQ you want, and the server app does the math to determine the correspnding IIR coefficients
We can only speculate at this point. It could also be that the code is client-side.
 
I'm glad that more DACs with PEQ are coming on the market, even if the particular device isn't available from European dealers.
 
As I understand it, you can only load one setting at a time. If you want to switch between different headphones with different settings, then as I understand it, you have to open the computer and load a new setting every time? Is it possible to load the settings locally on a computer as files, or must the user connect to their server and regenerate the same settings over and over again if you want to switch between different settings?
I haven't looked into the specific features of this JDS product, but conceptually speaking, you could easily have multiple groups of presets stored in DSP accessible memory. The coefficients, after all, are literally measured in bytes, not even kB's. So the JDS could store different PEQ settings, presets A, B, C and so on, and you could toggle among them using a button on the back.
 
From the photos of the PCB, there is no dedicated DSP at all, so the filters are apparently implemented in the XMOS chip's engine.


We can only speculate at this point. It could also be that the code is client-side.
I wasn't suggesting there is a discrete DSP "chip" in the product. Its a subsystem of the XMOS SoC (system-on-a-chip) of course.

As for the PEQ config code, from all the discussion above documenting what JDS has said on the blog, I don't think its speculation that the code is on the server. They outright said so. What is being speculated is that the same code could be run directly on laptops/phones/etc in the future, either by JDS shifting strategy or by releasing open source for people to implement as they wish.
 
Nah I don't think that's why they centralized it in a web app.
This might be closer to the reason, but my bet is that it is also easier for them to do web development instead of embedded, and cheaper to do one of the two instead of both. In my opinion this web app choice mainly serves their convenience at the expense of guaranteed functional longevity. I'd say why not make it fully self contained and offer the web app for the consumer's convenience who is happy and in the position to make all the required connections to enjoy a richer UI experience?
Lets be clear about the three potential domains to run this code: cloud server, client hardware (PC, phone) or the device itself.

Developing and maintaining embedded code to run directly on the limited resources in the Element IV would be a difficult effort and could have driven up BOM costs on the hardware, device size, etc. Also likely that, in the end, usability would suffer. You can say they took the "easy way out" by not doing this, but I think its a completely logical and defensible decision. Doesn't surprise me one bit that this avenue was categorically rejected. It does sacrifice guaranteed functional longevity, but that seems commonplace these days, for better or worse..

Now, the debate of implementing on client hw versus cloud hardware is much less clear. I'd guess that it was easier to develop server code accessed through a browser than to maintain two parallel iOS and Android apps.
 
Removed my comment @Inertiaman because I felt it was a bit too speculative on my part. Too late it seems but never mind.

It does sacrifice guaranteed functional longevity, but that seems commonplace these days, for better or worse..
In general I feel this trend could use more push back from the market. After 20 years a DEQ2496 is still relevant and being sold today despite its totally outdated external configuration facilities. In my opinion this should be the norm. I mean it's easy to think react will stay around for some time but what did your IT landscape look like in 2005?
 
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