[StanD]

Can we please get back to the original topic of AptX? Members view this thread because of its topic -AptX.

Headphone impedance/sensitivity/amp power is a different topic, which has been discussed elsewhere. Maybe take it to PM or open a new thread please. Thank you.

I think we've covered the OT stuff. Back to apt-x.

 

[Giogio]

Can we please get back to the original topic of AptX? Members view this thread because of its topic -AptX.

One of the first things I posted in this thread was this same sentence of yours.
Referred, in that case, to @james444 posting reviews of atpx receiver instead of talking of the aptx itself.
It was said to me, that "the theme aptx per se has been talked so much that there is nothing more to add. Since then people talk here of applications of aptx".
 
If talking of which aptx receivers have the best quality is not off topic, why should it be talking of how to chose the right aptx receiver?
 
Anyway. I kind of became allergic lately to off topic claims, so, it may be me.
Let's say that I do not want to discuss anymore.
I will eventually think about continuing asking elsewhere, if I need so

 

[zzffnn]

One of the first things I posted in this thread was this same sentence of yours.
Referred, in that case, to @james444
posting reviews of atpx receiver instead of talking of the aptx itself.
It was said to me, that "the theme aptx per se has been talked so much that there is nothing more to add. Since then people talk here of applications of aptx".

If talking of which aptx receivers have the best quality is not off topic, why should it be talking of how to chose the right aptx receiver?

Anyway. I kind of became allergic lately to off topic claims, so, it may be me.
Let's say that I do not want to discuss anymore.

I will eventually think about continuing asking elsewhere, if I need so

I actually consider James444's review of AptX on topic and helpful. It is difficult to dicuss AptX codec without mentioning actual implementation - products.

The " how to choose" questions you were asking are very basic questions that apply to all amplifiers and have nothing specific to BT AptX receiver/amp. Over the past two pages, StanD has already explained everything clearly - I suggest carefully reading that and other existing discussions and try to spend some time to understand it (instead if asking more off topic questions). In addition to what StanD and my previous posts told you on that topic, here are three more threads that you can read on or ask questions in (the third thread is a q and a thread for you):
http://www.head-fi.org/t/668238/headphones-sensitivity-impedance-required-v-i-p-amplifier-gain
http://www.head-fi.org/t/748297/confused-with-impedance-and-sensitivity
http://www.head-fi.org/t/607282/headphone-amp-impedance-questions-find-the-answers-here

I found those threads simply by searching in Headfi using key words "amp impedance sensitivity power". If you stay on Headfi long enough, you would understand that almost every senior member would have those kind of questions at some point when they shop for amps, thus those questions have been asked and answered over and over again.

A more relavent question would be, out of AptX receiver A vs. B, which one provides more power (or sound better) with headphone XYZ? You can ask that specific question regarding specific AptX receivers, if you still cannot figure out the answer yourself by reading what have been provided herein.

 

[Giogio]

And I'm not even a senior
I suppose one can see that the experience i have with Bluetooth headphones i do not have it with wired ones.
Yeah, i just could not leave Stan, knowledge is a contagious disease and i suffer of the mentoring syndrome, i always need to find someone who knows more than me and wants to transmit his knowledge.
But thanks for the links, they seems like the right place where to obtain contagion

 

[cityle]

I received the AT-PHA50BT and I really like them. I'm able to drive my K553 and my ATH-AD900x without problem (there is 16 steps of volume control and I stay at the 5th, 6th and 7th). I've only noticed a faint white noise while using them with my K553 (but you need to concentrate in order to perceive it and I will probably never notice it while on-the-go). I didn't notice any change in the sound and there is very little input lag compared to other bluetooth headsets I've used (usually there is like a 1-2 sec. of delay when you pressed on play or next track but not on these). Finally, they are smaller than what I though which is a plus.

 

[ClieOS]

I got the Creative BT-D1 a couple of weeks ago as my PC's aptX transmitter. One of the main reason for picking it is because it doesn't require any driver, and I reckon it was because Creative designed it in a way that the PC will see it as a USB DAC rather than a BT dongle - and I was right. Today, and just for fun, I plug it into my Xperia Z2 via an OTG adapter, fire up UAPP and HR Player and it works. Both see it as a USB DAC and I have it connects to my Creative E5's bluetooth without any issue. Of course I don't really need it to work on my Z2 since Z2 already has aptX built-in, but it is a proof of concept to add aptX support to Android smartphone that doesn't have aptX support. There is also a good chance that this might work on iOS via CCK, but I don't own any iPhone to test it. Just thought I'll report this in case anyone else wants to try.
 

 

 

[fnkcow]

Hey guys I have a question
Could this be attributed to weak amp inside the Noble BTS?
 
Quote:

  After waiting for 2 weeks due to some shipping mishaps, the Noble BTS has finally reached me today. It's much smaller than expected, as shown in photo below next to the white QCY and the black Elecom.

First thing I did was letting BTS charge fully for a couple of hours.
 
Using my A12, I noticed the static noise is present, on par with the QCY and less than the Elecom. Don't have anystatic noise if I plugged my A12 straight into my phone.
 
I was surprised to hear a very loud pop sound when I plugged my A12 into the BTS with it switched on, as I didn't expect it to since it's significantly less with the QCY and none at all with the Elecom so I never give much thought to it until I tried it on the BTS. Sure enough, tried a few times with all three and results are consistent.
 
Now comes the most significant issue I have with the BTS: it does not have enough juice to drive my multi BAs and hybrid IEMs. My A12 becomes bass anemic and the drop in bass quantity is huge. It's like the low frequency drivers simply stopped working. A12 only has an Impedance of 16 Ohms and sensitivity of +/- 117dB SPL @ 1mW. Strange. All my phones can drive my A12s okay. I've changed to my easy-to-drive IEMs and same thing happens. I've switched sources between my PC and phone a few times, switched IEMs and switched between the BTS, QCY and Elecom. All results are consistent. The bass is back with the other two, but missing with the BTS.
 
Wasn't expecting the BTS to be a miracle but then again wasn't expecting it to fall short either. 

 

  Dont have the BTS with me now atm.
Depends on the IEMs I'm using. The bass is still there, but really weak, especially on my A12. To give you a rough idea it's like switching from K10 to ER-4S in the bass department. 
 
Yes the bass difference for my IEMs are huge. I dont think it's the Bluetooth itself that's the issue though, as I have the other two Bluetooth dongles and also a Bluetooth headset Sony SBH80, all are aptx and Bluetooth 4.0 along with my sources, same as the BTS, but they output the sound with no issues like the BTS, and I already have the others for at least 3 months. 
 
IMO the BTS lacks a decent built-in amp as compared to my other Bluetooth ones. I bought this just expecting to drive my sensitive IEMs, not full-size headphones and the results are lacking. Having already heard the other Bluetooth dongles using various IEMs the difference is significant enough to me.
 

 

[StanD]

 
Hey guys I have a question
Could this be attributed to weak amp inside the Noble BTS?

Maybe. Do you get any distortion on loud passages or peaks? They don't give much in the way of specs. What does it use for a battery?

 

[fe-lixx]

I know this topic is about aptX, but since it's in the Science section and you're already discussing the Noble BTS, I figured I might just ask here.
 
No surprise, the chip in the BTS doesn't support aptX lossless, just the usual aptX, but Noble claims that it also supports ALAC (Apple Lossless) over Bluetooth. Is this even possible? I assume that only iOS devices would use ALAC, but could it be proven somehow that really ALAC is being used with the BTS and not just AAC, which the chip also supports?

 

[Jabbah]

From the Noble site the BTS uses the CRS8645 chip which supports aptX, MP3 & AAC but not mention of ALAC. I wonder if Noble made a mistake and it supports aptX lossless but someone put it down as Apple lossless.

http://nobleaudio.com/en/shop/wireless/

http://www.csr.com/sites/default/files/csr8645_bga_technical_overview.pdf

I also seriously doubt due to bandwidth constraints that FLAC / ALAC would be supported over Bluetooth. I think the max for this chip is 352kbps.

 

[Jabbah]

Actually it doesn’t look like aptX supports lossless at all. The lossless codec “aptX HD” is for non-BT applications:

http://www.csr.com/products/61/aptx-lossless

aptX will just use it’s 352kbps of bandwidth as efficiently as it can with as low as possible power requirements on the receiver.

 

[fe-lixx]

Nice find, I was under the impression that aptX lossless was a possibility for bluetooth devices, but the wording on that page is clear. Well, there's that.
 
Another thing that makes ALAC very unlikely is that it's an asymmetric codec, meaning the encoding takes a lot of power, while decoding is very lightweight. It would be a very weird choice for a bluetooth codec, and the first time ever that I've heard anyone doing that. Even Apple themselves don't offer or advertise any third-party bluetooth devices that support ALAC, and if anybody should be doing it, it's Apple.
 
Weird. Very weird.

 

[UnityIsPower]

I have the Sony SBH80 here and I've already noticed some cracking noise. It's more prominent if I play off my Amazon Music app but it's still audible with the Apple player and YouTube app. I'll keep playing with it. I'm on a iPhone 6.

The Stance S1 headphones I tried at a meet didn't have this issue in the time I auditioned them. I believe that's the last BT wireless gear I tried before these.

 

[bemymonkey]

Has anyone else noticed A2DP BT connection instability when around a lot of 2.4GHz WiFi?
 
I use a MiFi when out and about (basically a portable WiFi router that takes a SIM card and redistributes 3G and LTE to my laptop, phone, tablet etc.) and it only does 2.4GHz WiFi. When my phone (the playback device) is connected to this, my Bluetooth headset skips a beat every 20-40 seconds.
 
At home, where my phone connects to 5GHz WiFi, it plays skip-free. If I turn off WiFi on the phone, it also plays mostly skip-free.
 
 
My headset is an old Sony MW600, which doesn't support APT-X yet... would upgrading to an APT-X headset help? I have a Denon Envaya Mini (which supports Apt-X) that doesn't seem to exhibit these symptoms, but I don't use that nearly as much as the headset, so I'm not quite sure whether it's the Apt-X support that helps here.

 

[fnkcow]

I have the Sony SBH80 here and I've already noticed some cracking noise. It's more prominent if I play off my Amazon Music app but it's still audible with the Apple player and YouTube app. I'll keep playing with it. I'm on a iPhone 6.

The Stance S1 headphones I tried at a meet didn't have this issue in the time I auditioned them. I believe that's the last BT wireless gear I tried before these.

Hmm don't know about the pairing with iPhone as I use mine with Android phones but I don't experience the cracking noise. Maybe ask it over in the SBH80 thread and see if others have similar experience?
http://www.head-fi.org/t/752491/sony-sbh80-wireless-to-the-next-level-review