Fiio btr15

[Tremolo]

I realized that now you can choose the filter shape (peak, low or high shelf). But I still have issues with the stored eq, sometimes I find a flat line and my filters are lost

 

[gat3keeper]

I got Fiio BTR15 the other day having issues with Iphone 15 pro max + Tidal MQA files. For some reason it will just stop playing as if it will stop. I tried every setting but no go.

I updated the software to 3.5 and there's this "BYPASS" setting on EQ. Not it's working fine. MQA is not being played with no issue.

However, I don't have the audiophile ears and cant really tell the difference between expensive DACS vs apple dongle. I tried different dacs from cheap to expensive but all I can say is the advantage is more on features and convenience like volume control, EQ, gain, etc.. but not much on sound. Yes it improves " a bit " here and there" but cant justify spending more cash. Hahaha.

 

[ahofer]

I left my BTR15 in Mexico. Need to replace the unit and the Truthear IEMs I left with it.

What’s best now? I use it mostly with an iPhone. I found the Truthears a bit uncomfortable. I think the hosels are a bit wide for my ears.

 

[FlyingTeuton]

Mine is on FW 4.4. Today I found out that it has a weird and unreproducible fading in going on whenever playback starts, at least in PC mode under Linux. Sometimes the sound starts right away with the start of playback in the software, as you would expect, but sometimes it is muted first, and fades in within 0,1–1s, and most of the times on one channel quicker than on the other. Sometimes the right channel is quicker, sometimes the left. In fb2k via Wine it seems to depend on the file, too. And in VLC it happens every time I pause and resume playback. Utterly strange.

 

[jkim]

Mine is on FW 4.4. Today I found out that it has a weird and unreproducible fading in going on whenever playback starts, at least in PC mode under Linux. Sometimes the sound starts right away with the start of playback in the software, as you would expect, but sometimes it is muted first, and fades in within 0,1–1s, and most of the times on one channel quicker than on the other. Sometimes the right channel is quicker, sometimes the left. In fb2k via Wine it seems to depend on the file, too. And in VLC it happens every time I pause and resume playback. Utterly strange.

The BTR15 has two separate firmware releases, one for BT and the other (XMOS) for USB connection. Is yours on the latest XMOS firmware (V125)?

 

[FlyingTeuton]

Thanks, I’ll try, somehow. I found the XMOS upgrade on the Fiio webpages. Of course it’s Windows only Windows 10/11 only. I don’t have either, and right now I won’t set up a VM for that.

 

[mugmealer]

The BTR15 has two separate firmware releases, one for BT and the other (XMOS) for USB connection. Is yours on the latest XMOS firmware (V125)?

Hi there, I think I saw your post on the Fiio Forum stating that despite updating to the latest firmware for both BT and XMOS, you were still not getting the correct PEQ response. Is that still the case? I've been looking to purchase this for the sake of having PEQ for use with my iPhone and iPad since Q5K is not available for sale in my country.

 

[jkim]

Hi there, I think I saw your post on the Fiio Forum stating that despite updating to the latest firmware for both BT and XMOS, you were still not getting the correct PEQ response. Is that still the case? I've been looking to purchase this for the sake of having PEQ for use with my iPhone and iPad since Q5K is not available for sale in my country.

THe BTR15 does not give correct PEQ response for USB connection. No firmware has been released to resolve this issue. Have not measured its BT PEQ response yet.

What headphones are you going to use? Is BT absolutely necessary?

EDIT. The Qudelix store ships worldwide. Try that. The shipping cost is worth it IMO.

 

[mugmealer]

THe BTR15 does not give correct PEQ response for USB connection. No firmware has been released to resolve this issue. Have not measured its BT PEQ response yet.

What headphones are you going to use? Is BT absolutely necessary?

EDIT. The Qudelix store ships worldwide. Try that. The shipping cost is worth it IMO.

I don't need BT, just need a USB solution with reliable PEQ for use with iOS devices. Have seen that Qudelix ships worldwide, but customs cost a bomb here, which would make the total cost twice as much. I use AKG K701, HD600, N5005, IE200, and a few other budget IEMs.

I've been looking at the feasibility of using DAPs in USB DAC mode and making use of onboard system-wide EQ. I understand that defeats the portability factor, but are there any budget DAPs that can work this way, where the EQ gets applied to the analog output in the USB DAC mode?

 

[jkim]

To be honest, there are not many options if you need onboard PEQ AND decent output power to drive your headphones with some global preamp cut.

I still think the Qudelix 5K is worth it even if you have to pay double the price..

 

[FlyingTeuton]

So, it could be, that the PEQ response is different over BT than over USB?

 

[jkim]

So, it could be, that the PEQ response is different over BT than over USB?

Yes, I haven't yet tested its BT PEQ response.

 

[jkim]

Yes, I haven't yet tested its BT PEQ response.

Finally measured the BTR15's PEQ response. Below is copied from this post.

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Measured the FiiO BTR15 (both USB and BT connections) and KA15 for their peak and low-shelf filters.

Peak filters first:

Issues to be solved:

• BTR15 in USB connection: The Q factor input NOT correctly translated. It seems that Q = 1.0 is misinterpreted as Q = 0.707.
• BTR17 (USB mode) and KA17: Same issue was observed.
• BTR15 in Bluetooth connection: Although the response is overall correct, there is a peaking around 20 kHz (see below for comparison with Qudelix 5K).

Low-shelf filter responses:

Issues to be solved:

• BTR15 in USB connection: Completely wrong response.
• KA15: The Q factor input NOT correctly translated. It seems that Q = 0.71 is misinterpreted as a "shelf slope" S = 0.71 (or Q = 0.5).
• BTR17 (USB mode) and KA17: Same issue of Q factor mistranslation was observed.
• BTR15 in Bluetooth connection: Although the response is overall correct, there is a peaking around 20 kHz (see below for comparison with Qudelix 5K).

I will contact FiiO and ask them to provide solutions.

I further tested the BTR15's PEQ performance in Bluetooth connection by comparing it with the Qudelix 5K:

Note. The Bluetooth (LDAC) playback of test signals was from the USB Audio Player Pro (UAPP) installed on Google Pixel 8.

There is certainly a problem with the BTR15's LDAC performance, not achieving the sample rate of 96 kHz.

Measured the dynamic range of both devices' LDAC modes:

It seems that the BTR15's Bluetooth LDAC mode has some kind of clocking/jitter issue, making its FFT unstable---the skirt around the test tone is fluctuating over rolling averages.

The Qudelix 5K's Bluetooth performance (and its PEQ accuracy) is exemplary, explaining why it has been regarded as the best of its kind for quite a while.