The Leben CS300XS Thread

[ardilla]

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My CS-600 was purchased new in April so it seems safe to assume it has the lower power output. All of my gear is powered by (2) PS Audio Power Plant Premiers which removes the quality of the AC power from the wall as well as voltage issues from the table. The tubes have been rolled using NOS RCA and Sylvania black plates although the hum issues were present with the stock valves as well.
 
Mine exhibits a low level hum with the HD650, a headphone that I still listen to on occasion since even though there has been incredible breakthroughs in hp technology since their introduction, these cans with the right source and amp, can still make for enjoyable listening. Currently I am using the SS Bakoon AMP-R11 with them and they sound alive and exciting in comparison to the EAR HP4 using NOS RCA's.

 
I do not know about the CS-600, if there ever was a higher vs lower-power/sensitivity headphone output.
 
 
About the CS-300X(S) specifically, the Leben [size=12.727272033691406px]Managing Director[/size] himeself wrote me that there was two versions, and the they previously delivered the lower power version as standard, but could install the other version on demand. It is, as I stated, only two resistors that should be changed, any amp-mechanic could do that.
 

[size=12.727272033691406px]In the past there were two types of CS-300X, one has 1000mW headphone[/size]
[size=12.727272033691406px]output, and the other has 800mW for high efficiency headphones.[/size][size=12.727272033691406px][/size]
[size=12.727272033691406px]Your CS-300X should be with 1000mW headphone output for low efficiency[/size]
[size=12.727272033691406px]headphones, therefore, the noise shall be improved by reducing the[/size]
[size=12.727272033691406px]headphone output power from 1000mW to 800mW.[/size]. 

 
At what impedace the 800/1000 mW is measured I do not know. Probably in the thirties (?)

 
Again - I have posted the diagram and the resistor values in question HERE

 

[ardilla]

Same here. We probably have the same version (higher power/for less effeicient cans) 
 
Actually - I am happy to have the DA11 in front of it, so I can use it to calibrate the volume a bit more finely. Not a necessity, nut nice. 
 
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High powered output?  I don't know if I would even want that (maybe my version already has it) since I never turn my volume control past 10 o'clock,  Usually it is barely at 9.

 

[Dr. Roberts]

Quote:

 
I do not know about the CS-600, if there ever was a higher vs lower-power/sensitivity headphone output.
 
 
 

 
Regardless of whether the headphone output circuitry of the two Leben integrated models is different or not, the fact of the matter is that we both experience the low level hum when paired with the HD650. This "low level hum" issue is the problem I have using my Leben as a headphone amplifier with certain models of headphones. I find the "low level hum" to be unacceptable, especially when a number of synergistic alternatives are available that do not exhibit this background noise.

 

[ardilla]

Yup. 
 
One possibility is to change the resistors. 
 
Another possibility is to add an extra headphone output (drill a hole and add a TRS) for a high-sensitivity output. That would be neat, and a simple job for someone qualified. 
Quote:

 
Regardless of whether the headphone output circuitry of the two Leben integrated models is different or not, the fact of the matter is that we both experience the low level hum when paired with the HD650. This "low level hum" issue is the problem I have using my Leben as a headphone amplifier with certain models of headphones. I find the "low level hum" to be unacceptable, especially when a number of synergistic alternatives are available that do not exhibit this background noise.

 

[Dr. Roberts]

Quote:

Yup. 
 
One possibility is to change the resistors. 
 
Another possibility is to add an extra headphone output (drill a hole and add a TRS) for a high-sensitivity output. That would be neat, and a simple job for someone qualified. 

 
If there are things that I do know for certain, they are my own limitations, and your suggestions, both of which may very well resolve the problem, would fall into that category. Living without the Leben even for a few days, please keep in mind that I'm old-school and use the Leben frequently to power speakers, does not strike me as an attractive thought.
 
Much easier for me to plug into the Bakoon AMP-11R when in the mood for the HD650 which is an SS amp, not well known on Head-Fi by any means, but has been said to be in First Watt territory by some sources with a sound signature similar to a fine SET amplifier.

 

[Skylab]

Dr. Roberts to answer your earlier question, I've not heard the Liquid Fire except at meets, so I really can't offer a comparison.

 

[ardilla]

@Dr.Roberts: The Bakoon looks very intriguing. Do you have more to tell about it?

 

[Dr. Roberts]

Quote:

@Dr.Roberts: The Bakoon looks very intriguing. Do you have more to tell about it?

 
I should probaby refer you first to this link so you can read Srajan's pearls of "wisdom".    http://www.bakoonproducts.com/review/amp-11r-review-6moons/    This is the only review of the amp in the English language.
 
I have been in contact with Soo In of Bakoon International. He sent me this review in Polish.    http://highfidelity.pl/@main-1508&lang=   Just use the Yahoo "Translate" tool.
 
From Soo In's personal experience, he recommends the HD650 and HD800 as being the most synergistic but he seems to be more of a speaker aficionado although he is now in the process of auditioning various headphones. I tend to believe that he is realizing that more and more of his customers from around the world are purchasing his amp for headphone usage.
 
Once you have assimilated the background info, if you have any specific questions regarding the amp, I would do my best to answer them although I would suggest a personal message as to not derail the thread any more than I already have.

 

[ardilla]

Sure - thanks. Found the 6moons and the Bakoon homepage . But ot much headphone-specific info. 
 
Please contribute here: http://www.head-fi.org/t/640158/bakoon-amp-11r-headphone-and-integrated-amplifier
 
Now back to Leben
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Once you have assimilated the background info, if you have any specific questions regarding the amp, I would do my best to answer them although I would suggest a personal message as to not derail the thread any more than I already have.

 

[Dr. Roberts]

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Dr. Roberts to answer your earlier question, I've not heard the Liquid Fire except at meets, so I really can't offer a comparison.

 
Too bad, I value your opinions and reviews. Thanks for responding.

 

[vert]

I had something that was beyond a hum. I was pleasantly surprised the LCD-3s are dead quiet.

 

[ardilla]

How was it beyond a hum? With what gear?
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I had something that was beyond a hum. I was pleasantly surprised the LCD-3s are dead quiet.

 

[zoroastra]

Quote:

 
If there are things that I do know for certain, they are my own limitations, and your suggestions, both of which may very well resolve the problem, would fall into that category. Living without the Leben even for a few days, please keep in mind that I'm old-school and use the Leben frequently to power speakers, does not strike me as an attractive thought.
 
Much easier for me to plug into the Bakoon AMP-11R when in the mood for the HD650 which is an SS amp, not well known on Head-Fi by any means, but has been said to be in First Watt territory by some sources with a sound signature similar to a fine SET amplifier.

For what it's worth, I sold my First Watt F3 to buy a Leben CS300Xs and have been much happier with the sound of the Leben than I was with the First Watt. I drove the First Watt with an Audiable Illusions Mod 3A pre-amp which may (or not) contribute to the difference. I have very high sensitivity speakers (>100 db/watt/meter) that, with the Leben but not with the First Watt, do emit a 50 cycle hum when idling, but that goes during playback and the sound of music being played is lovely, especially with the 45 RPM re-cuts like Clarity from Classic Records.
 
I personally am willing to put up with a little hum in exchange for the quality of sound that comes with Leben. They come closer to that magical place where one can suspend disbelief and think one is listening to live music. I believe that if I ran less sensitive speakers, some that do not take the output to the speaker and amplify the bass portion more with mosfet amps in the crossover as mine do, that there would be no hum, but then, I might loose a bit of the sound quality.

 

[vert]

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How was it beyond a hum? With what gear?

 
With HD600 and Phonak 232. It was almost like a buzzing/static. It was definitely not the low hum that goes away when the music plays, as other owners have described. Though I think buzzing had more to do with my environmental setup.

 

[ardilla]

All I hear is the 50 Hz-ish hum, only bothersome at quiet passages with sensitive headphones.  I had som tubese however, that picked up various noise on the AC line. 
 
Did you try swapping tubes etc?
Quote:

 
With HD600 and Phonak 232. It was almost like a buzzing/static. It was definitely not the low hum that goes away when the music plays, as other owners have described. Though I think buzzing had more to do with my environmental setup.