Knowledge Zenith (KZ) impressions thread
Jul 26, 2017 at 7:29 AM Post #19,246 of 63,834
It's interesting that ZSE doesn't use an over ear design like the rest of the ZS series.
Cable down design gives you more mobility i guess...

The ZSE is for a completely different marketshare than the ZS5 as shown by the rrp.
ZS5 is just getting cheap as they start to phase it out.
KZ have done many cable down designs over the years
 
Jul 26, 2017 at 8:34 AM Post #19,247 of 63,834
This is my first experience with a IEM, and after some days with a pair of ZS5 I must admit these are a truly jewel. They have better level of detail than my other headphones, Fidelio X2 and Beyerdynamics DT 770 250 ohm. They are surprisingly good with jazz and classical music. They meet the most complex passages with great solvency. I'm using generic comply foams. The silicon tips don't isolate very well. My only complain is confort, but I suppose this is common to most of IEM.

Have a good day, friends :beyersmile:

About confort, I had to get ride of the memorie part of the cable.
I'm waiting for my ZS5 to arrive, meanwhile still in love with ZS3 after that tweak in the cable, before that I couldn't get use to them too.
 
Jul 26, 2017 at 9:25 AM Post #19,248 of 63,834
OK, so I shielded my KZ bluetooth cables to (partially) eliminate radio interference.

MAKE SURE TO READ THE FULL UPDATE BELOW AS WELL!!

1. Make sure the BT module is turned OFF before beginning. Then you'll need a razor blade, kitchen paring knife, razor blade, guitar pick, etc. Use it to gently split the case at the seam. There is no glue holding it together - it's just clipped together.



2. Once you have it apart, you'll be able to see the guts - battery and microusb port on 1 side, and on the other side the antenna and the bluetooth chip (a Wind Tunnel WT200 chip, which a Google search has verified that both of my cables are the correct bluetooth 4.2 & aptX chipset). Here's what it looks like:




Note that with the board outside of the case, the cable has to be handled CAREFULLY using kid gloves. The wires that are soldered onto the board are very tiny, and if you handle the module like a burly gorilla you'll rip the cables right off the board at the solder joints. Once out of the case, I only handled the module by holding the circuit board module itself - I didn't not pull on or twist the cables themselves. You have been warned.

3. Now you'll need some sort of foil tape. I used the aluminum type used for heating and air conditioning applications. You can also use copper tape. Both types are very thin, and have an adhesive backing. You want to cut a thin strip just about 1mm less than the width of the bluetooth chip. Then peel off the backing, and cut off a small piece large enough to cover the top of the chip, BUT NOT LARGE ENOUGH TO HANG OVER THE EDGES! The reason for this is because you don't want any of the metallic tape to contact the pins on the outside of the chip, or you will short out and damage your bluetooth module. The goal is to have about a 0.5mm edge around the whole chip that does not have any tape. This way you ensure the piece isn't too large. You have been warned. I've illustrated this concept here:





If you can't get or don't have any of the aluminum or copper tape, you can use standard aluminum foil (and attach with a TINY amount of super glue applied using a toothpick). I strongly recommend the adhesive-backed tape though. With super glue there's potential for screwing it up (using too much glue, gluing the aluminum foil on crooked, etc. With the adhesive backed tape, you can peel it off and redo it if there is ever an issue, vs the permanence of super gluing standard aluminum foil. But it's up to you.

4. Next cut 1-3 more pieces of the same size and add them on top as additional layers. I used a total of (4) layers of tape because I used aluminum. If you are using copper tape, you can use (2) layers (because copper will shield better than aluminum, so you have to use more aluminum).

5. Make sure the little plastic button piece is inserted where it belongs in the housing, then carefully put the board back into the housing (putting the cable reliefs back where they go in the ends). Then clip the housing back together and you're all done. I didn't have to use any glue because the clips were all intact when I first took the case apart. If you happened to break some of the clips, use a drop of super glue (applied w/a toothpick) when you put the case back together.

6. Turn on the module and test to make sure it's working. I did both of my cables (ZS3/ZS5 and ZST) in one sitting - each one took about 10 minutes from start to finish.

I've been testing the cables for the last few hours, and so far haven't had any skipping due to interference (ie doing the things and in the same places that I previously experienced interference). If anything changes, I'll let you know.

UPDATE: It seems that I spoke too soon. Indoors, the shielding fix seems to have corrected all interference. Outdoors, it's sadly another story - it's still interference city, and the constant skipping makes me want to stomp the bluetooth cable into oblivion! I don't know if it's a radio interference issue, an antenna design issue, a crap BT chipset, or a BT power issue. Maybe KZ has the BT power output level cranked down ridiculously low to provide maximum battery life (but so low that the connection is easily overpowered by extraneous radio signals). Regardless, I'm forced to relegate the KZ bluetooth cables to indoor-use only (in the house & possibly at the gym). But at this point, I strongly recommend against the purchase of the KZ bluetooth modules.

Both of my cables act consistently (the latest version ZS3/ZS5 and ZST cables, purchased from different sellers). Since others report the same cutting out/interference behavior, this seems to be a product design flaw, not an isolated QC issue with 1 or 2 cables.

Damn that's too bad after all that.
 
Jul 26, 2017 at 9:27 AM Post #19,249 of 63,834
Jesus, about 30 hours use with these (zs5) and I can't believe how freaking good these sound! It's unbelievable how cheap these are.....

What king of voodoo is this?

voodoo.gif
 
Jul 26, 2017 at 9:35 AM Post #19,250 of 63,834
The ZSE is for a completely different marketshare than the ZS5 as shown by the rrp.
ZS5 is just getting cheap as they start to phase it out.
KZ have done many cable down designs over the years

Phase it out? The ZS5 is just released?
 
Jul 26, 2017 at 10:39 AM Post #19,252 of 63,834
Jul 26, 2017 at 11:42 AM Post #19,254 of 63,834
Damn. I think I'm better off with the ZSE than getting a replacement cable for my ZS3 I mean, the right earpice will work if I wear the cables at a certain position (the damage is on the part of the cable that is tucked in behind the ear or in between the plug and the cable). Guess I'll at least wait for reviews for the ZSE. Plus a local seller is claiming that there is a new silver plated cable specifically for the ZS3 that is similar to the new straight plug spc for ZST.
 
Jul 26, 2017 at 12:39 PM Post #19,255 of 63,834
Damn. I think I'm better off with the ZSE than getting a replacement cable for my ZS3 I mean, the right earpice will work if I wear the cables at a certain position (the damage is on the part of the cable that is tucked in behind the ear or in between the plug and the cable). Guess I'll at least wait for reviews for the ZSE. Plus a local seller is claiming that there is a new silver plated cable specifically for the ZS3 that is similar to the new straight plug spc for ZST.

SQ is an unknown for ZSE. Although I did order. At the price there is little risk.
 
Jul 26, 2017 at 3:25 PM Post #19,256 of 63,834
OK, so I have an update to the KZ bluetooth cable shielding mod posted here: https://www.head-fi.org/f/threads/k...essions-thread.698148/page-1282#post-13621972.

It turns out the problem is the length of the antenna. It is too short (24mm total). I have no clue how or why they came up with that length, but that is NOT the correct length for a generic PCB-trace style bluetooth antenna. The CORRECT length for a quarter-wavelength bluetooth antenna should be 31mm, not 24mm.

If you want to read more about the topic, here is some info that explains the details: http://bluflux.com/bluetooth-antenna-design-guide-step-1/

If you don't understand any of the nerdy mumbo jumbo, don't sweat - the takeaway is that the KZ antenna is 7mm too short.

Anyways, to correct the problem, all you have to do is extend the stock antenna with a piece of wire.

1. Pop the case apart and remove the board. For details about how to do that, read the shielding mod link I posted above. Next scrape away the coating at the very tip of the antenna until about 1mm of bare copper is exposed (I used an Xacto blade). Don't scrape away too much or too hard or you will scrape the copper trace right off the board.

2. Now you need to solder some sort of small piece of wire to the exposed "pad" you made on the antenna. The best thing to use is the leg from some sort of through hole component (an LED, carbon resistor, etc). I used a small piece of wire, but only because I was lazy to find an unneeded through-hole component. Antennas should really be solid core wire, not stranded wire like I used. But I wasn't even expecting this to work so I really didn't care at the time. When I repeat the mod on my 2nd KZ bluetooth cable, I'll use the leg from a resistor.

3. Anyways, once you have the piece of wire soldered on, trim it to exactly 7mm longer than the end of the stock antenna. Why not cut it before soldering? It's easier to solder a longer piece of wire and cut it down than to try and solder on a tiny piece of wire. Plus the wire needs to be 7mm longer than the END of the stock antenna, so cutting it after soldering ensures that you aren't counting any material that overlapped the stock wire at the solder joint. In other words, when you look at the photo below, the wire is actually about 8mm long, with 1mm of that length overlapping a section of the stock antenna for soldering purposes. Make sense?

4. Once the wire is soldered, pull the battery away from the back of the board (it's held on by some sticky tape), and wrap the antenna extension around the board. Stick the battery back on the same spot and reassemble the board into the plastic case. The wire is small and thin enough that the case needs no modification whatsoever.

5. Because I've had my case apart a number of times now, the clips don't hold as well as they did the 1st time I put it together. So I just used a few strategically placed drops of super glue to hold the 2 halves of the case together and I was done. Note that you shouldn't need any glue if you've never had the case apart. I only needed a few drops of glue because I've had the case apart numerous times.


What are the results of the mod? How about DOUBLE THE RANGE with ZERO skipping and interference indoors or outdoors! Yeah for science!

Now that I've seen what's going on, I believe this was the issue all along. There is no need to shield the bluetooth chipset with foil like I showed yesterday. Just do the antenna mod outlined here and you're golden.

Here's a few photos. The 1st photo shows the extension wire soldered onto the end of the stock antenna (after trimming to 7mm). The 2nd photo shows the antenna folded over onto the back side of the board.

Antenna_mod1.JPG
Antenna_mod2.JPG

You're probably thinking - what a PITA for a $7 bluetooth cable. KZ could have just as easily designed the antenna correctly from the get go. I agree, but at least I can finally use my cables without any annoying skipping, so in that respect it was worth the trouble spent.

The mod itself is technically easy, but you would want to have decent soldering skills, a sharp pointed soldering iron, and good eyesight because the wire is so small. If you've never done anything like this, have someone help you or do it for you. Total time from start to finish was about 20 minutes.

Enjoy!
 
Jul 26, 2017 at 4:00 PM Post #19,257 of 63,834
OK, so I have an update to the KZ bluetooth cable shielding mod posted here: https://www.head-fi.org/f/threads/k...essions-thread.698148/page-1282#post-13621972.

It turns out the problem is the length of the antenna. It is too short (24mm total). I have no clue how or why they came up with that length, but that is NOT the correct length for a generic PCB-trace style bluetooth antenna. The CORRECT length for a quarter-wavelength bluetooth antenna should be 31mm, not 24mm.

If you want to read more about the topic, here is some info that explains the details: http://bluflux.com/bluetooth-antenna-design-guide-step-1/

If you don't understand any of the nerdy mumbo jumbo, don't sweat - the takeaway is that the KZ antenna is 7mm too short.

Anyways, to correct the problem, all you have to do is extend the stock antenna with a piece of wire.

1. Pop the case apart and remove the board. For details about how to do that, read the shielding mod link I posted above. Next scrape away the coating at the very tip of the antenna until about 1mm of bare copper is exposed (I used an Xacto blade). Don't scrape away too much or too hard or you will scrape the copper trace right off the board.

2. Now you need to solder some sort of small piece of wire to the exposed "pad" you made on the antenna. The best thing to use is the leg from some sort of through hole component (an LED, carbon resistor, etc). I used a small piece of wire, but only because I was lazy to find an unneeded through-hole component. Antennas should really be solid core wire, not stranded wire like I used. But I wasn't even expecting this to work so I really didn't care at the time. When I repeat the mod on my 2nd KZ bluetooth cable, I'll use the leg from a resistor.

3. Anyways, once you have the piece of wire soldered on, trim it to exactly 7mm longer than the end of the stock antenna. Why not cut it before soldering? It's easier to solder a longer piece of wire and cut it down than to try and solder on a tiny piece of wire. Plus the wire needs to be 7mm longer than the END of the stock antenna, so cutting it after soldering ensures that you aren't counting any material that overlapped the stock wire at the solder joint. In other words, when you look at the photo below, the wire is actually about 8mm long, with 1mm of that length overlapping a section of the stock antenna for soldering purposes. Make sense?

4. Once the wire is soldered, pull the battery away from the back of the board (it's held on by some sticky tape), and wrap the antenna extension around the board. Stick the battery back on the same spot and reassemble the board into the plastic case. The wire is small and thin enough that the case needs no modification whatsoever.

5. Because I've had my case apart a number of times now, the clips don't hold as well as they did the 1st time I put it together. So I just used a few strategically placed drops of super glue to hold the 2 halves of the case together and I was done. Note that you shouldn't need any glue if you've never had the case apart. I only needed a few drops of glue because I've had the case apart numerous times.


What are the results of the mod? How about DOUBLE THE RANGE with ZERO skipping and interference indoors or outdoors! Yeah for science!

Now that I've seen what's going on, I believe this was the issue all along. There is no need to shield the bluetooth chipset with foil like I showed yesterday. Just do the antenna mod outlined here and you're golden.

Here's a few photos. The 1st photo shows the extension wire soldered onto the end of the stock antenna (after trimming to 7mm). The 2nd photo shows the antenna folded over onto the back side of the board.




You're probably thinking - what a PITA for a $7 bluetooth cable. KZ could have just as easily designed the antenna correctly from the get go. I agree, but at least I can finally use my cables without any annoying skipping, so in that respect it was worth the trouble spent.

The mod itself is technically easy, but you would want to have decent soldering skills, a sharp pointed soldering iron, and good eyesight because the wire is so small. If you've never done anything like this, have someone help you or do it for you. Total time from start to finish was about 20 minutes.

Enjoy!

You....

macg.gif
 
Jul 26, 2017 at 4:40 PM Post #19,259 of 63,834
OK, so I have an update to the KZ bluetooth cable shielding mod posted here: https://www.head-fi.org/f/threads/k...essions-thread.698148/page-1282#post-13621972.

It turns out the problem is the length of the antenna. It is too short (24mm total). I have no clue how or why they came up with that length, but that is NOT the correct length for a generic PCB-trace style bluetooth antenna. The CORRECT length for a quarter-wavelength bluetooth antenna should be 31mm, not 24mm.

If you want to read more about the topic, here is some info that explains the details: http://bluflux.com/bluetooth-antenna-design-guide-step-1/

If you don't understand any of the nerdy mumbo jumbo, don't sweat - the takeaway is that the KZ antenna is 7mm too short.

Anyways, to correct the problem, all you have to do is extend the stock antenna with a piece of wire.

1. Pop the case apart and remove the board. For details about how to do that, read the shielding mod link I posted above. Next scrape away the coating at the very tip of the antenna until about 1mm of bare copper is exposed (I used an Xacto blade). Don't scrape away too much or too hard or you will scrape the copper trace right off the board.

2. Now you need to solder some sort of small piece of wire to the exposed "pad" you made on the antenna. The best thing to use is the leg from some sort of through hole component (an LED, carbon resistor, etc). I used a small piece of wire, but only because I was lazy to find an unneeded through-hole component. Antennas should really be solid core wire, not stranded wire like I used. But I wasn't even expecting this to work so I really didn't care at the time. When I repeat the mod on my 2nd KZ bluetooth cable, I'll use the leg from a resistor.

3. Anyways, once you have the piece of wire soldered on, trim it to exactly 7mm longer than the end of the stock antenna. Why not cut it before soldering? It's easier to solder a longer piece of wire and cut it down than to try and solder on a tiny piece of wire. Plus the wire needs to be 7mm longer than the END of the stock antenna, so cutting it after soldering ensures that you aren't counting any material that overlapped the stock wire at the solder joint. In other words, when you look at the photo below, the wire is actually about 8mm long, with 1mm of that length overlapping a section of the stock antenna for soldering purposes. Make sense?

4. Once the wire is soldered, pull the battery away from the back of the board (it's held on by some sticky tape), and wrap the antenna extension around the board. Stick the battery back on the same spot and reassemble the board into the plastic case. The wire is small and thin enough that the case needs no modification whatsoever.

5. Because I've had my case apart a number of times now, the clips don't hold as well as they did the 1st time I put it together. So I just used a few strategically placed drops of super glue to hold the 2 halves of the case together and I was done. Note that you shouldn't need any glue if you've never had the case apart. I only needed a few drops of glue because I've had the case apart numerous times.


What are the results of the mod? How about DOUBLE THE RANGE with ZERO skipping and interference indoors or outdoors! Yeah for science!

Now that I've seen what's going on, I believe this was the issue all along. There is no need to shield the bluetooth chipset with foil like I showed yesterday. Just do the antenna mod outlined here and you're golden.

Here's a few photos. The 1st photo shows the extension wire soldered onto the end of the stock antenna (after trimming to 7mm). The 2nd photo shows the antenna folded over onto the back side of the board.




You're probably thinking - what a PITA for a $7 bluetooth cable. KZ could have just as easily designed the antenna correctly from the get go. I agree, but at least I can finally use my cables without any annoying skipping, so in that respect it was worth the trouble spent.

The mod itself is technically easy, but you would want to have decent soldering skills, a sharp pointed soldering iron, and good eyesight because the wire is so small. If you've never done anything like this, have someone help you or do it for you. Total time from start to finish was about 20 minutes.

Enjoy!
I honestly did not experience any skipping or interference with both my KZ ZST and ZS5 Bluetooth cables so far. Could this be a batch issue?
 
Jul 26, 2017 at 5:23 PM Post #19,260 of 63,834
So I just got a chinese foam tips (t400/500 equivalent) from aliexpress and theya re a must for ZS5. comfort increased dramatically and sound isolation seems a tad better too. sound didn't really change, maybe a bit more e base is noticeable (because of better seal perhaps?) recommended as per the first impressions.
 

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