repair

DeLonghi Coffee Machine Sound Modification

/ Kai / 2 Comments

About a month ago I stumbled across a thread (in German) about improving the sound of DeLonghi ESAM coffee machines. It was said, that with rather few changes the sound profile of the machine can be significantly improved. I’ve used a necessary complete overhaul of our DeLonghi Magnifica ESAM 4500 (Pronto Cappuchino) coffee machine to also add this modification…
…with more or less significant improvements. Only two parts are necessary:

  • The ULKA EP5 pump was swapped for an Innensys CP4/SP.
  • The DeLonghi pressure relief valve was exchanged by a Saeco membrane filter (sorry, no type/model number available).
The original DeLonghi pump.

The original DeLonghi pump.

The new parts installed in the DeLonghi ESAM 4500.

The new parts installed in the DeLonghi ESAM 4500.

The membrane filter and the pump (originally intended for Saeco coffee machines).

The membrane filter and the pump (originally intended for Saeco coffee machines).

The new pump and membrane filter both let the coffee machine sound much deeper and calmer. Although the new pump has about 20 W more ‘power’, it runs a bit slower (about five seconds for one cup of coffee, as shown in the figure with the acoustic profiles).

Comparison of the acoustic profile of the DeLonghi ESAM 4500 before and after the modification.

Comparison of the acoustic profile of the DeLonghi ESAM 4500 before and after the modification.

I’ve also made a video which shows (or should I say: plays 🙂 ) the before/after effect. The most significant change can be heard after the coffee was grounded, when it is actually poured into the cup.

Logitech M705: How to fix a defective mouse button

/ Kai / 93 Comments

I’m a big fan of Logitech mice, or at least was until a few days ago. My wireless Logitech M705 started to behave strangely: Pressing down the left mouse button resulted in multiple clicks (i.e. double-clicking) and dragging became impossible due to random interruptions when holding down the button.

Without a warranty (which had expired three months ago) I did not feel guilty when opening the mouse to look for the cause. The culprit was quickly found: the microswitch of the left mouse button. Luckily, I had spare microswitches as I’m currently playing around with the optical sensors from other spare/defective mice. I will cover this in another post. To come to the point: after replacing the microswitch, the mouse works again as usual. I’ve made a few photos (a picture is worth a thousand words 😉 ) to help others during disassembly of the housing. Screws are marked red, and I have also marked (in yellow) two tiny springs that can easily be lost.

This fix has a bad aftertaste: at least in Germany, there is much talk about “planned obsolescence”, and I’m wondering if Logitech (and other manufacturers) use cheap microswitches that only survive a certain number of clicks. Especially after my mouse showed the previously mentioned defect so soon after the expiry of the warranty… On the other hand Logitech kept its promise regarding the battery life – I’m still using the first set.

Update (2014-11-22): Just as a brief clarification, after I got some feedback on the M705. (Apparently several users have had similar experiences.) Logitech uses Omron switches that actually seem to be pretty good. So I want to point to posts from Kogos and Ralf  below: First you should try what is recommended in a Logitech forum post. After that you might try resoldering the joints. If that doesn’t help an exchange might be the best option…

Klipsch S4i: Repair broken earbud headphones

/ Kai / 48 Comments

Note: Please also read the comments as there are updates & fixes available!

Update: I’ve fixed the graphics showing how the different bundles of cables should be attached to the connector. A big thank you to Rock for correcting me on this!

I am a fan of good-sounding in-ear headphones and bought a Klipsch S4i for my iPhone 3GS. I am really impressed by its quality and they are not overpriced (around 80.- € when I bought them). Last month, the connector on the headphone cable began to loosen. I tried to fix it with cyanoacrylate adhesive but a few days ago the cable finally broke (resulting in a dead left channel and microphone).

I am pretty sure this type of defect is not covered by the manufacturers guarantee (another point: I purchased them over two years ago) so I didn’t bother disassembling the connector. The first thing I did was removing the plastic cover of the connector with a utility knife.

The soldering spots are enclosed in clear plastic. I tried to remove the plastic and gently desolder the cables from the connector, but the connector broke (actually it melted). At least I was able to identify the six bundles of thin twisted wires.

Corrected Cable Assignment for the Klipsch S4i Headphone


I separated the colors and twisted them together into four bundles (one for each contact on the connector) and resoldered them onto another spare connector. The fixed connector lacks the ‘stylish’ finish it previously had, but the shrinkable tubing makes a good protection for the thin wires. And the complete functionality is back, including the microphone and the control buttons.

Update: The new Klipsch S4i model has a revised (improved) kind of connector. Maybe I was not the only one with a broken cable…

Update for users of the Android version (Klipsch Image S4 II) headphones.
A big thank you to “WCSTUR” (whoever you are) for sharing this information per e-mail:

Changes to your wiring diagram for the Klipsch Android version:
TIP – green wire (always left earbud)
Band 1 – red wire (always right earbud)
Band 3 – the 2 earbud copper wires AS WELL AS the red and blue-green shield wires for the microphone. This band is the ground. (Your diagram shows the microphone red and green-blue shield wires connected to the earbud wires. Your diagram may also work since the earphone impedance to ground is only about 18 ohms for each of these earbuds.)
This wiring follows what I dissected from the original plug.