[francisdemarte]

Someone was kind enough to provide a link to this amp on ebay in the Matrix M-Stage thread. I thought I would be a great amp around 1/2 the price of the M-Stage and an easy DIY project to pass the time.
 
 


EDIT 04/13/2011: You can now buy the Lovely Cube Premium fully assembled.

For details: http://www.alicemagicbox.com/lasercollection/lovelycubepremium.html




Hardware
 
 
The "Lovely Cube" is sold on ebay by Laser Collection. It runs about $100 shipped for a fully populated board, a pair of nice quality RCA jacks, some heat shrink, a few SIP connectors for the inputs, and a couple of LED's.
 
The vendor also sells the rest of the components you need to complete the amp: 220v transformer and case as well as unpopulated boards.
 
The Lovely Cube is an exact copy of the Lehmann BCL where the Matrix M-Stage is a slightly altered version. Here's some pictures I borrowed from the ebay auction:
 
 
 

Bottom of the board with the Gain adjustment DIP switches.
 
 

 
Alps volume pot
 


Swappable opamps. I switched the SOP + adapter for the DIP8 version of the OPA2134 I had laying around.
 
 

 

 
The amp arrived via normal HK Post about 2 weeks after I ordered it. All components look to be name brand and high quality.
 
Be aware that it came with no instructions of any sort, so you'll have to be a little familiar with DIY. In the picture above I've labeled all the wiring points for everyone's reference. 
 
On the far left is the primary input, grounds in the center and signals are the outer connectors.
The center 3 connection points output 15V DC. It is used in the USB version of the Lehmann BCL to power the DAC and USB ports. Pretty nice addition since you can use it with a voltage regulator to power a DIY DAC.
 
Next to that is the 2nd inputs, I believe these are muted if you plug a headphone into the 2nd headphone jack. I did not connect this in my installation.
 
Lastly the power input with convenient screw terminals. The amp has an internal PSU so all you need to provide is a 15V AC transformer.
 
Here's a internal picture of a real Lehmann to get an idea of how things look wired up.
 
 

 
 
Sound
 
Going to reserve this space for further impressions. My current install in a old external CD-Rom chassis powered by the DY-1 power supply that came with the Head Direct EF-5 amp set at 16V AC.
 
I have a minor grounding issue since my case does not have a faceplate. I hear buzzing on my low Z phones when I touch the volume pot, I think I need to ground it to the case. I'll update this section once I get a new case or get this issue resolved.
 
Edit 07/07/2010: Buzz is now gone. I had to ground the Alps pot to the star ground in my case. The amp is now totally silent with no music playing and the volume turned all the way up with my 42 Ohm ATH-W1000X's.
 
 
Initial Impressions
 
I'm not the best amp reviewer here but the review of the Matrix M-Stage's sound signature all applies here. This is a fantastic amp for the price! Fast, dynamic, and works well with all my headphones.
 
Currently I have mine set at gain 0 and it really brings my ATH-W1000X to life. The bass goes low and hits effortlessly and the mids, while still forward are smooth. The HD650 also sounds great at gain 0!
 
 
Initial Conclusion
 
This is a steal at around $100 shipped for a finished board. If you have a little DIY experience or want to get your feet wet without the complexities of putting together an entire amp this is a great start!
 

Mods

Thanks to JiggaD369 for compiling a list of mods mention in this thread!

http://www.head-fi.org/t/501046/the-lovely-cube-headphone-amp-lehmann-black-cube-linear-clone/915#post_7966068
 
 
I basically went through the entire thread about three times in order to condense all of the info. This is basically my first complete DIY modding project and mostly out of curiosity. It was painful but worth it IMO!

Below are the mods with Newark/Farnell part numbers (otherwise noted):


PSU:
Replaced the two 4700uf caps with United KMH caps (16M6799).
Replaced the ADJ caps with Sprague10uf tantalums (30C8841).
Replaced the R2 resistors with zener diodes as per BlaBla method (18C6023).
Replaced the regulators with Fairchild (58K8936/58K8937).
Replaced the four transistor 470uf caps with Panasonic FC (80K8337).

Signal Path:
Bypassed input caps with 6N copper wire.
Replaced the stock opamp with OPA2111KP.
Replaced the two opamp supply caps with Silmic II's.
Replaced the two small 0.022uf caps bypassing the Silmics with Philips (.027uf) Polystyrene caps. (Ebay)
Replaced the output 10 ohm resistors with Allen Bradley 1W carbon resistors (Ebay).
Replaced the 100pf caps with LCR Polystyrene caps (64K0006)
 
 
 
 
 
 
Thread Highlights & Updates
 
Edit 07/07/2010: Upped the gain to 10, which gives the HD650's a bit more oomph while still leaving some headroom for the W1000X's. 
 
Edit 08/31/2010: The ebay seller now as an official site for the Lovely Cube: http://www.alicemagicbox.com/lasercollection/lovelycube.html
 
Edit 09/24/2010: Sunneebear creates the first balanced Lovely Cube Amp! http://www.head-fi.org/forum/thread/501046/first-impressions-lovely-cube-semi-diy-amp-lehmann-black-cube-linear-clone/75#post_6948982
 
Edit 10/01/2010: Comparison between Lovely Cube and Matrix M-Stage with the HE-5: http://www.head-fi.org/forum/thread/501046/first-impressions-lovely-cube-semi-diy-amp-lehmann-black-cube-linear-clone/105#post_6964362
 
Edit 10/13/2010: ebay seller now has OPA627AU and Class A adapters available. Nichicon KG Gold Tune 4700uF 50V replaces the Elna for Audio 4700uF 35V caps on new units. Some pictures by aspenx http://www.head-fi.org/forum/thread/501046/first-impressions-lovely-cube-semi-diy-amp-lehmann-black-cube-linear-clone/105#post_6990039
 
Edit 11/14/2010: Removed output caps replaced with solid core wire, opens up sound stage a bit and increases treble extension. 
 
Edit 11/29/2010: Is your Lovely Cube case feeling very warm? Relax, it's suppose to be that way: http://www.alicemagicbox.com/lasercollection/lovelycubesecretofheat.html
 
Edit 01/16/2015: Corrected and updated schematics. Thanks Habibelhabab! http://www.head-fi.org/t/501046/the-lovely-cube-headphone-amp-lehmann-black-cube-linear-clone/1170#post_11021088
 

 
 

 
 

 

06/10/2016:
 
More technical discussion from diyaudio.com:
 
http://www.diyaudio.com/forums/headphone-systems/285380-headamp-upgrading-lehmann-bcl-clone.html 
 
 
Some board were found with manufacturing defects that caused persistent hum. This thread offers a solution:
 
http://www.diyaudio.com/forums/headphone-systems/271057-100hz-hum-lehmann-linear-clone.html

 

[francisdemarte]

 
Some pictures of the board in my temporary enclosure. Forgive my poor photography, it was late.
 
 

 
Wired up and powered up for the first time
 

 

 
Encased in a old SCSI cd rom enclosure. Still have to fix the stand off screw .
 

 
Powered up and stacked up. Laptop > Gamma2 DAC > Lovely Cube powered by Hifiman DY-1 (From EF5 amp)
 
 

 

[prospero21]

Looks very promising. As im in the market for a new headamp (my Zero died on me after 2 yrs of faithful service) and I might try going the DIY route, this would fit the bill nicely.
I'll most certainly will keep an eye on this topic for the days to come.
 
What would be good dac companion for this board ? http://cgi.ebay.com/MUSE-HIFI-USB-S-PDIF-Converter-USB-DAC-PCM2704-/120576181155?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item1c12e683a3 maybe ?

 

[francisdemarte]

Quote:

Looks very promising. As im in the market for a new headamp (my Zero died on me after 2 yrs of faithful service) and I might try going the DIY route, this would fit the bill nicely.
I'll most certainly will keep an eye on this topic for the days to come.
 
What would be good dac companion for this board ? http://cgi.ebay.com/MUSE-HIFI-USB-S-PDIF-Converter-USB-DAC-PCM2704-/120576181155?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item1c12e683a3 maybe ?

It's a nice basic DAC but probably won't be on par with your Zero. 

 

[reiserFS]

Got a link to the seller's shop? Can't seem to find anything under "Lovely Cube". For under 100$, this might become my first DIY amp.
 
Edit: Nvm, found it.

 

[aspenx]

Thanks for the writeup!
 
Looking forward to more information on this lovely cube.

 

[francisdemarte]

Ebay auction is here:
 
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200482693027&ssPageName=STRK:MEWAX:IT#ht_11841wt_1101
 
Seller is: Lasercollection
 
PM him directly for lower prices or the cost of other parts.

 

[francisdemarte]

Pictures added! Next up will be comparison between the Lovely Cube, EF-5, and Aune (Graham Slee Solo clone).

 

[aspenx]

Wow. You're right.
 
The quote for the metal case is very high. This is my first time with DIY and I'm wondering how I'm going to get a case for this...

 

[francisdemarte]

I used an old external CD-ROM case cost me nothing.
 
Cheapest route is to recycle some old electronics. Ask your friends, go to your local junk shop, garage sale, or your neighbors trash and look for old audio video equipment. They are nice because they will already have a power jack and RCA plugs built in, all you have to do is rip the rest of the stuff out.
 
Even cheaper you can use a cookie tin, wooden craft box or even a cardboard box. Just have to watch that it doesn't catch fire
 
Or else theres the pricier DIY route. Find a vendor that sells cases and ships to your country. 
 
Like this one:
http://www.diyfidelity.com.au/index.php?cPath=36&osCsid=4136e1b146c69d0a36722e803f5d5c3d
 
 
 

 

[aspenx]

Does that mean the RCA jacks are not provided in the "package"?
 
Will I be correct to say that in addition to the board, I'll be needing a case, RCA jacks, power jack, a transformer (which I think I can get for $10 locally), some form of knob for the potentiometer and some jumpers?
 
Yes, I've seen CMOY amps in Altoid cans (only online though). Very amusing...
 
But something wooden and cherry wood like will be nice to match the W1000X.

 

[SpudHarris]

Looks great........
 
I've asked him about the enclosure, I'm assuming it's expensive?

 

[aspenx]

I was quoted 30 GBP. Might not be expensive to most (?) people here.
More details on the case:
 
Quote:

[size=10pt]1) 6mm thick aluminum front panel
2) 2mm thick metal body
3) 2 ready holes on the bottom for 2 dB switch
4) IEC fused socket included
5) 30 mm Dia Full aluminum knob included[/size]

 

[francisdemarte]

 
It's $57 shipped, no too bad considering it has a pre-drilled front plate, but the added cost put you very close to a finished M-Stage.
 
Here's what I was quoted.
 
1) Finished Board : US$93  (if outside ebay, rebate all ebay charge : discount US$7 , i.e. US$86)
2) Shipping of above board :  US$14
3) Metal case : US$42
4) Combined shipping (HK-USA) for Metal case : US$15
 
Total amount for outside ebay : US$86 + 14 + 42 + 15 = US$157
 
You'd still need a transformer that outputs 15V 1Amp transformer You can get one for around $30 from mouser/digi-key/farnell/parts-express etc.
 
Assuming you have wires, soldering iron, wire stripper etc. your looking at about $200.
 
Might I suggest someone put together a group buy! I would do it but I have a wedding in 1.4 months.

 

[aspenx]

Deleted post cause I realised I wasn't making any sense.