[lotec25]

double post

 

[scratje]

There are dozens of threads on the net about rewiring and adjusting Z5500 systems to even work without a pod but i never found a usefull one so far.
I even used a control pod bypass cable from Ebay but the sound is terrible and you lose the handy input modes like PLII movie and PLII music.
Search for a second hand pod and ask the seller for the pid number that will match your system. Upgrading to another woofer in the sub will not allways mean a better sound because of the design of the sub enclosure which has to match with the woofer specifications and the other way around.

 

[lotec25]

So now I am back to my original problem. The speakers are popping and cracking again. I found a few caps in the pod bulging so i replace them, I also replace the 3 big caps on the sub amp. I also replaced the cord on the Pod cause it seamed every time i moved it it would stop popping and cracking. But its now doing it again. I still need to replace the rest of the caps on the sub amp and pre amp but not very confident that is going to fix it either. It did stop for a while after doing the caps so not sure what to do to fix the issue. Does anyone have suggestions?

EDIT, does anyone know what rotary encoder the pod uses? i checked the solder joints, it's been running now for well over an hour with no popping or cracking, Thinking I should just replace it to make sure something is not going bad on the inside contacts.

Thanks

 

[Rama Chandra]

Hello everyone, I was silent about my experiment in Hungary. I went home and fired up the soldering iron and opened up my relative's Z5500 one more time. I can confirm it got dustier since, otherwise look the same like on the pictures on the first thread. I have no photos to show thanks to my pathetic "spy phone" and I lost all the images.

Basically I wanted to test how much the sound of the Z5500 can improve by bridging the film capacitors on the signal path in the system, then doing a similar job in the JBL (not original Logitech) speakers.

Soldering on the pins of the electrolyte caps some small film capacitors was known to me beneficial for a long time to help higher frequencies, because the films have a more balanced frequency response, and in general smaller caps do a better job to handle high frequencies. I was also aware the silver mica capacitors are one of the cleanest but harsh unforgiving components for audio. Anywhere I used them in my external DACs analogue section there was reason to respect them but very little reason to love them. Polystyrene (styroflex) always done a better job to keep.

Something popped up in my mind years ago, why I'm not using them only on the signal path to help the high frequencies to pass? Then I built an amplifier that way and I could not be happier with the results. Somehow I was not thinking to bring it any further for years.

The time had come and I bridged each K73-16 0.47uF caps with another Soviet era 10nF 500V KSO mica capacitor. This little addition for the "Third Mod" will bring the sound to a new level of clarity or could improve your speakers if you had replaced them. I have to mention here, he still using his old SB Titanium, and already have similar mod over the decoupling capacitors for the same purpose. Only difference there, I used 0.1uF 63V film caps alone, unfortunately. Unfortunately because if I used silver mica in addition at the time the result could have been even a bit better now. I did not prepare with components for this type of surgery, while I was there.

Then the next step was to replace all the old electrolytic capacitors in the JBL speakers. I only used my favourite K73-16 film plus the above mentioned silver mica for the tweeter. What better the tweeter need to produce the best high frequencies? It is clear, it is sharp, it is unforgiving, and bite.

When I was done in the Sub, I recap the front left speaker and turned on the system for listening. My relative was not sure he like the new speaker more, than the old yet. I asked should I stop? He not encouraged me to do so. It was a struggle to squeeze in all this much larger components into the speakers. When I done the other front speaker, another listening test followed. This time he was sure this upgrade is the future.

Then all the satellites was done and getting late at night (I already felt sorry for his neighbours) he went through some music files, and blasted loud his loved movies. He mentioned: I have not heard this detail, that detail, and even on low volume the system produce a clean sound now....

Later on at home, I done the same silver mica trick on my Cambridge Audio speakers, and on another. Now I like this speakers, before I was always disappointed with them. Simply they lacked the clarity to impress a headphone lover like me. When I got this speakers, after an hour listening I could not take it anymore and I was digging out the Chinese electrolyte c(r)aps from the speakers, even that meant warranty is surely void. You could think a reputable company will use something decent for audio. Dream on. After the upgrade this little addition years later was still required.

 

[felix3650]

Very nice thread this one.

So I got myself a Pod-less Z5500 (newer Pid) along with what appears to be a not working bypass cable (3.5mm jack with volume going to a D-Sub connector).

Any good schematics out there to build my own working Pod bypass?

 

[YiouJr]

Hello to all members of this thread,

I wanted to post that starting from this relatively simple upgrade, I took it some (many) steps further. So, in some long steps, I completely ditched the control pod and replaced it with one of my own design. The reason for this is that pod's DSP has embedded high pass filters for the satellites. In effect, any bypass for the control pod could lead to frying the satellites in high volumes. But in my case I replaced the satellites with high end full sized 6.5" bookshelfs in front and 4.5" for the rear to handle the now present bass. My newly created control pod serves primarily preamplification purposes, using 3 OPA1612, Standby & Mute functions and gain trimmer controls for each channel. I've also added switches for stereo x4 or x6, with center and woofer playing L/R combined. Furthermore, I added 2 LPFs for the sub forming one second order passive filter, with adjustable cut off from 28Hz to the original 125Hz.

Secondly, I removed all opamps from the board along with their smd components. Yes, the 2 opamps for the woofer as well. I re-implemented the circuits for the speakers, which implement DC signal protection instead of replacing them with the 0.47uF cap. Plus, there is already a capacitor in the signal path to the TDAs, and another capacitor in series reduces the total capacitance, and in combination with the 22k input resistor forms a HPF which would be undesirable. I also removed those smd capacitors and replaced them with 2.2uF.
Instead of the 2 opamp preamplification circuit for the woofer I made a circuit with one opamp, with gain and crossover trimmer controls like those I added to my custom head. The reason I also ditched this part is because the crossovers for the woofer let it play in the range of 35-125Hz which is too high. Now there is no bottom range, leading to a SUBwoofer. My current design's cut off isn't steep enough, so I have mine set to 28Hz to avoid those mid tones.
Next, there are 2 22uF caps for each TDA7294. I removed the one in the signal path (the other is the bootstrap), which serves as a subsonic (HPF) filter to further improve the low bass response for the speakers. I soldered the pins together. In the same concept, for the same reason I also removed the 100uF NP cap in the back of the board.
Now that the system handles some real bass it was time to replace the bootstrap caps. The original 22uF isn't enough for hitting down in the 10Hz range. I replaced them with some low ESR 68uF 50V caps, but 47uF should also do the trick.

I can't really describe how the system responses now, those low notes are absolutely hammered.
It seems I am too new to forum to figure out how to upload images, but I guarantee the head and the board look beautiful

 

[scratje]

You almost made en total new amplifier so i am curious to what you did and how with pictures to show.
You can share pictures in your replies by selecting the image button as shown with the red arrow and select an image on your pc

 

[YiouJr]

It doesn't allow me to upload photos directly from my computer, it must have to do with the account being new. It only accepts URL images, and I already tried 2 unsuccessfully.

Anyway, my design isn't flawless, the narrower frequency for the sub (3-28Hz until the cut off) requires a whole lot of more gain and on top of that the subwoofer box is tuned to 40Hz. That much gain introduced some quiet noise. I also want to steepen the crossover, and I'm thinking of introducing one more second order crossover, active this time. I could harvest one more gain of 1.5 this way too.

For such high gains a balanced connection is the way to go, but a little hard to implement with 3.5mm jack plugs.

 

[YiouJr]

You almost made en total new amplifier so i am curious to what you did and how with pictures to show.
You can share pictures in your replies by selecting the image button as shown with the red arrow and select an image on your pc

Today that I checked again I can upload images! So, here is my creation!

 

[RTAA]

Guys,

i need small help. So i got z5500 for almost 10 years, but it started to make noise sound from all speakers. No matter of source it was same.
I took them to repair shop and they said problem is with CS42526 proc in control unit. But since they dont have it they were unable to fix.
Meanwhile i purchased another z5500 set which had same issue. Finally i was able to buy another control pod and connect to rest of my unit and problem gone.
Now i would like to fix my control pod, i got brand new Cirrus Logic CS42526 but from what i was told it needs to be programmed first.
Are you aware of any place i could get firmware from so it can be programmed and replaced in my control unit.
Any help would be highly appreciated!

 

[l0NeXuS0l]

I found this video that made my system silent, after a period of constant noise.
Las link can help someone.



Now I have another problem with the control pod.
When the switch is turned off and I want to turn it on, the control pod lights up directly, I press the button to turn it off, the light bulb turns red, but the display still shows, and I can change anything, volume or effect, when pressing the button the LED turns blue, everything is exactly as it was when it was off, the difference is that the lights on the display turn off.
Another problem is that it has a strange noise in all the speakers, which increases with the volume.
It is not permanent, a small (POC) sound is heard a few seconds away.
It's as if the sound is hanging on.
Has anyone ever encountered this problem?

 

[Katsukare]

Hi all.

I haven't been active on this forum for a while now but still own three Z5500 units, two older types and one new type.

For those of you who want to completely modify the older type Z5500 and want to get rid of the big thump/boom/pop when switching other devices in the house, hereby a few pics from the preamp board with Wima MKP10 film capacitors to replace the green ceramic capacitors and the axial 220nF film capacitors to replace the SMD caps.

By sodering the Wima film caps on the backside of the board, you will have enough space to place them properly and it looks more organised too.

The axial 220nF film capacitors can be soldered by first removing the SMD capacitors on the backside of the preamp board and use jumper wire to connect the solder leads.
Then remove the resistor on the other side and put the axial 220nF capacitor in series with the removed resistor. Look carefully how the signal path goes so the capacitor comes first and the resistor second!

Furthermore i soldered two 100nF 275V X2 suppression caps between the AC leads of both the rectifier and placed a big ferrite ring over the AC main power wires with 3x twist trough the ferrite core.
Secure the ferrite with tie wraps and hot glue to prevent opening and hanging lose inside the amplifier case.
With the two suppression caps and the ferrite ring, the big tump/boom/pops will be almost gone!
In the newer Z5500 systems they did the same thing.

For the other modding on this older type, search my name 'scratje' and you will find how to do the rest with older systems.

I will try to do another mod but it will be experimental.
I want to completely rotate the mainboard 180 deg. so the big caps come near the rectifiers with shorter dc wires so the signal wires wil be more separated and hopefully pick up less noise. There will be some desoldering involved and new wires must be made but maybe the unit will be less humming on the subwoofer driver and hiss on the satellites but this is still a guess.
Maybe a metal cap over the torodial transformer can have an effect too, so there are more experiments to do.

have fun modding

Thank you for these photos, did this modification remove the terrible hissing noise when the unit is powered on without input/sound?

 

[scratje]

Thank you for these photos, did this modification remove the terrible hissing noise when the unit is powered on without input/sound?

No, just to prevent the boom at start or when switching other devices in the room and the 50/60 Hz humm from the woofer will be almost gone.

 

[l0NeXuS0l]

How about connecting two subwoofers to a single POD Control.
I leave a link with the video:

 

[Samare]

Hi,

I've noticed that the Z-5500 consumption is, with S/PDIF:

• ~10 W when off
• ~23 W after turning it on (without input signal)
• ~38 W once it has received some input even it stopped

I've also always been annoyed by the need to turn it on and off.

Now, the JBL Media 200 has an auto turn-on/turn-off feature:

They will turn off when the source equipment (computer or CD player) has no sound output for approximately fifteen minutes and immediately turn back on when a signal is present.

I'd like to achieve that with the Z-5500.

I've thought about using an Arduino Nano or a Raspberry Pi Pico inside the control pod, to poll the input signal and control a relay.
Note that when the control pod is disconnected from the sub, the consumption drops to ~0 W. So the relay could cut that connection, then resume it and turn on the pod when a signal is detected.

Does anyone have any ideas or pointers?