[438555]

Output Impedance: < 2.5 Ohms (High-Sensitivity) < 1 Ohms (Ultra-Sensitivity)

You can find some additional info and explanation in our tech notes on IEmatch here: https://ifi-audio.com/wp-content/uploads/2018/07/iEMatch-Tech-NotesJune17.pdf

Hi, I just got the signature and have been enjoying it with several different headphones. One of which is the SE846 IEM, which have a pretty low impedance, and not even across frequencies. Sensitivity-wise, I pretty much need it to be at Eco mode and Ultra-Sensitivity. I'm reading here that in the Ultra mode the output impedance is lower than in High. So am I right in thinking that a 1 Ohm impedance shouldn't change the frequency response of these appreciably, even though they dip below 8 Ohms in the treble? The graph here shows what it is with nominal 0 Ohm and 20 Ohm amp impedance, but I'm not sure of the math on how many dB response will change depending on relative impedances.

 

[Jmm722]

Is there anything I can attach to the iDSD to allow me to use Bluetooth? I want to be able to move around my apartment and office with my source stating put and just keeping the iDSD in my pocket. I have a Qudelix 5k, but I don’t believe that’ll work since it’s 3.5 or 2.5mm out.

 

[hoofman]

Is there anything I can attach to the iDSD to allow me to use Bluetooth? I want to be able to move around my apartment and office with my source stating put and just keeping the iDSD in my pocket. I have a Qudelix 5k, but I don’t believe that’ll work since it’s 3.5 or 2.5mm out.

The iDSD has RCA output no? If the Qudelix 5k has 3.5 input will an RCA to 3.5mm cable work?

 

[Johnfg465vd]

Is there anything I can attach to the iDSD to allow me to use Bluetooth? I want to be able to move around my apartment and office with my source stating put and just keeping the iDSD in my pocket. I have a Qudelix 5k, but I don’t believe that’ll work since it’s 3.5 or 2.5mm out.

You can attach a budget DAP, I'd recommend the HiBy R2 to use as a USB transport. Stack the R2 and Signature and connect them both with a USB Cable. Connect your phone to the R2 with Bluetooth and enjoy. There's also the Topping BC3, less features compared to R2 but more simple to use.

If you need better sound quality then load an SD Card with your music and put it in the R2. Connect the R2 & your phone with HiBy Link to control music playback. This way, you won't be sending audio via a lossy codec like bluetooth but just control the playback of R2 on your phone.

The iDSD has RCA output no? If the Qudelix 5k has 3.5 input will an RCA to 3.5mm cable work?

Qudelix does not have a 3.5 Input, even if it did have such an option. Why would you want to use Qudelix as an Amp over the iDSD's internal one? I'm going to assume you meant to use the Qudelix as a DAC connected via Bluetooth and want to use it's 3.5 Out to connect the iDSD. Sadly, this also won't work, unlike the previous iDSD (Black Label) the Signature does not support Analog Input.

 

[hoofman]

Qudelix does not have a 3.5 Input, even if it did have such an option. Why would you want to use Qudelix as an Amp over the iDSD's internal one? I'm going to assume you meant to use the Qudelix as a DAC connected via Bluetooth and want to use it's 3.5 Out to connect the iDSD. Sadly, this also won't work, unlike the previous iDSD (Black Label) the Signature does not support Analog Input.

Oh you are right silly me! I was thinking qudelix as a receiver then output to iDSD but I got it in the wrong direction!

 

[438555]

Is there anything I can attach to the iDSD to allow me to use Bluetooth? I want to be able to move around my apartment and office with my source stating put and just keeping the iDSD in my pocket. I have a Qudelix 5k, but I don’t believe that’ll work since it’s 3.5 or 2.5mm out.

Probably better off using a Wi-Fi enabled DAP or something so you can stream to that from your source. Will work better than Bluetooth over a wider area. What source are you using now?

 

[Jmm722]

Probably better off using a Wi-Fi enabled DAP or something so you can stream to that from your source. Will work better than Bluetooth over a wider area. What source are you using now?

I use my iPhone or laptop. I’m not sure if I’m permanently working from home or going hybrid, so I wanted a one-size fits alls (semi-portable, but good as a desktop combo).

I’m likely getting an Th-900 or other dynamic and then a planar (Edition XS, Audeze 2 or X). I’m not sure what I’m going with, but I wanted portable power to maximize potential uses.

I hadn’t really considered a DAP because I don’t want to spend a lot and want a lot of power. Plus, my friend offered me his iDSD for $400.

 

[438555]

I use my iPhone or laptop. I’m not sure if I’m permanently working from home or going hybrid, so I wanted a one-size fits alls (semi-portable, but good as a desktop combo).

I’m likely getting an Th-900 or other dynamic and then a planar (Edition XS, Audeze 2 or X). I’m not sure what I’m going with, but I wanted portable power to maximize potential uses.

I hadn’t really considered a DAP because I don’t want to spend a lot and want a lot of power.

A relatively cheap DAP like the HiBy R3, strapped on to the iFi, and connected via USB or SPDIF

 

[iFi audio]

A relatively cheap DAP like the HiBy R3, strapped on to the iFi, and connected via USB or SPDIF

A DAP as transport for an external DAC/amp seems to be the shortest and celanest way to go if one doesn't want to involve his/hers smartphone.

 

[slsmaster]

Oh you are right silly me! I was thinking qudelix as a receiver then output to iDSD but I got it in the wrong direction!

Just buy a Topping BC3. That is the best solution to make the Signature Bluetooth capable, some users here at headfi already did this. Also way cheaper and more compact then using a DAP. Qudelix can’t be used as an input for Sig, as it has no analog input, only digital.
See here:
https://www.head-fi.org/threads/ifi-audio-idsd-signature-the-saga-continues.944241/post-16379352

 

[438555]

A DAP as transport for an external DAC/amp seems to be the shortest and celanest way to go if one doesn't want to involve his/hers smartphone.

So far with mine, I’ve just been using my phone directly for walking around, and I haven’t yet noticed the same issues with RF noise from the LTE/Wi-Fi that I’ve had in the past with my Oppo HA2, and mojo. For those I moved to a DAP for that reason, and used downloaded files and turned off networking. Maybe the larger size, or position if components in the signature makes it less prone to RF noise

 

[iFi audio]

Hi, I just got the signature and have been enjoying it with several different headphones. One of which is the SE846 IEM, which have a pretty low impedance, and not even across frequencies. Sensitivity-wise, I pretty much need it to be at Eco mode and Ultra-Sensitivity. I'm reading here that in the Ultra mode the output impedance is lower than in High. So am I right in thinking that a 1 Ohm impedance shouldn't change the frequency response of these appreciably, even though they dip below 8 Ohms in the treble? The graph here shows what it is with nominal 0 Ohm and 20 Ohm amp impedance, but I'm not sure of the math on how many dB response will change depending on relative impedances.

It depends on the specifics of the headphone as to whether the bass or treble (or other) is affected. micro iDSD Signature has an output impedance of 4/0.94 ohms in IEM high/ultra sensitivity setting. The graph shows a bass reduction and HF lift with lower impedance. From 4 ohms to 1 ohm the response would change by less than 1dB. It won’t be as audible as the reduction in background noise, which will dominate the change in sound quality.

 

[438555]

It depends on the specifics of the headphone as to whether the bass or treble (or other) is affected. micro iDSD Signature has an output impedance of 4/0.94 ohms in IEM high/ultra sensitivity setting. The graph shows a bass reduction and HF lift with lower impedance. From 4 ohms to 1 ohm the response would change by less than 1dB. It won’t be as audible as the reduction in background noise, which will dominate the change in sound quality.

Thanks!

 

[iFi audio]

Thanks!

Sure, anytime!

 

[Knee Deep In Epoxy]

A long time ago I promised a comparison between the Hiby R2 and the Shanling Q1 here as both can be used as transports with the ifimidsds (I'm not writing it all out!) to bring Bluetooth via USB.

Firstly, Sorry for the delay to the guy to whom I promised the comparison.

Here's the dilemma:

If you plan to ONLY use the device as a bluetooth source for the ifi, my experience with the R2 was better. Using the Q1 and switching apps, e.g. from Qobuz to YouTube would often cause the signal to break. I would need to disconnect and restart the whole set up again which is annoying. The R2 was much more stable. Soundwise, there was barely a difference. Presumably they should both be passing digital to the ifi and relying on the burr brown DAC to take things forward.

The R2 also seemed to have a better user interface but neither are great really.

But if you were to venture off and use the R2 and Q1 separately, not with the IFI, I much prefer the Q1, both aesthetically and for sound quality. It's so much more resolving than the R2. Everything is clearer, and with better tonal balance and timbre.

Also I seem to have issues with the playback with the R2 when using it Alone to receive BT from my phone and play directly out of its 3.5mm output. Tracks start to get jumpy and I need to restart/reconnect the R2. The Shanling is stable when used standalone. None of the connectivity issues I had when using the Shanling with the IFI.

In the end I've gone back to using the IFI wired.