| Power Supply Caps: | Mundorf MLytic |
| Signal Capacitors: | Mundorf MCap |
| Internal Cabling: Feet: Fuse: | Mogami Neglex SSC vibration absorbing feet AHP Fuse |
It sounded excellent with my HD650s and my Beyer T1s...
Modifying a Lovely Cube to take it close to the Lehmann SE version.....
I have taken a Lovely Cube, replaced some parts, built an outer case and made my own version of a LEHMANN AUDIO BLACK CUBE LINEAR SE headphone amp.
I bought a Lovely Cube which had been assembled by someone else, from 'a well known auction site', and when it arrived, it sounded VERY good. I could not believe that on this clone, even the circuit board said LEHMANN, and the front panel, instead of being printed with the words 'LOVELY CUBE', actually said Lehmann Audio Black Cube Linear'. Naughty....
However, I had been reading about the SE changes that Lehmann had used in their latest version, and thought that I'd have a go at modding it.....
The changes I made were:
1. Replace the 2 Power supply caps with Mundorff AG Electrolytics.
2. Replace the 6 capacitors at the front of the main board with larger Panasonic FC types.
3. Replace the input caps with the same ones that Lehmann uses: Mundorff 2.2uF polypropylenes.
4. I also decided to upgrade the Toroidal transformer to a higher VA. I changed it from a 30VA to a 60VA. The original Lehmann and Lovely Cube ones are 15-0-15s. However, my Lovely Cube had arrived with a 18-0-18 transformer, so I decided to stick with that voltage. I JUST managed to cram it in!
5. I also replaced the input cables with Mogami Neglex Quad microphone cable, which is similar to that which Lehmann use on the SE.
6. I tried an OPA2111AM IC and loved it, but I thought I could go one better. I put in a Class A resistor Bias board. That helped! Then I thought why not reduce crosstalk even further by using MONO chips, the OPA111AM on a Stereo to Mono board. The result is in the pics.
7. Out of sight, I put a pure silver audio fuse, hidden away in the fuseholder, just like Lehmann do....
8. Under the circuit board, I bypassed the 2 main capacitors with 2 small polystyrene caps.
9. I used car sound deadening panels to help deaden the main metal panels of the casing.
10. I made an outer case out of perspex (acrylic) sheet 3mm thick. I have access to a laser cutter, so this was easy. Lehmann use an extruded aluminium outer case, veneered, so I veneered my acrylic on the top and sides with genuine Santos Rosewood. I used a cabinet scraper to get it smooth, and then gave it 2 thin coats of finish.
11. I masked the case and spray painted the inside front silver.
12. I bought some SSC feet, the same ones that Lehmann use on their SE, and fitted those.
13. The inner case is fitted to the outer case using the ORIGINAL bolts which had held the original rubber feet.
What do you reckon?
The first pic is of the beautiful, genuine, Lehmann SE headphone amp range....
And here is my home-made, not for profit own version....
Santos Rosewood veneered casing...
...have to fix those scratches on the silver interior....
...you can see the edge of the black acrylic casing...
SSC isolation feet...
...outer casing (above in pic) and main casing (below) separated for clarity...
...ditto...
2 Mundorff Electrolytics, 2 Mundorff M-cap polypropylenes, larger transformer and Mogami Neglex Quad cable...
6 Panasonic FC capacitors, and the dual mono IC board with 2 OPA111AM chips, sitting atop a Class A BIAS adaptor...
Clearer view of the dual mono IC and Class A adaptor underneath...
Mogami Neglex Quad cable. This is REALLY good cable!
The changes have REALLY opened up the sound.....cymbals shimmer and bass notes are clearer but feel deeper... separation between instruments and voices is more naturally pronounced, but most importantly, the Pace and the sense of people playing together is there. It almost sounds as if the players are more professional, because the sound, whilst clearer, is more coherent.
Now I need to look at a few other issues....
The next thing I want to look at is the output transistors, the BD139 and BD140. I have a load of genuine Philips BD140-16s, but no BD139s. I have loads of non-Philips stuff, but if anyone has any Philips BD139-16s, I will willingly swap some Philips BD140-16s for them....
Then there's the other elec components....not sure which to change as a priority...any suggestions, guys?
)
