LEBEN CS300F Integrated Amp with matching LEBEN RS30EQ Phono Stage

I am using the Klipsch RP160M with my triode wired el84se amp. Maybe 1,5 watts class A. Love the sound of the combination!!

@Stenak

It's fantastic that you have found a joyful loudspeaker match for your low-powered EL84 SET amp.

We used to have a tubed (1.5W) TRANSCENDENT SOUND Original SE-OTL, which was NOT nearly enough power to find joy driving our own KLIPSCH RP160M loudspeakers.

I am really surprised that your EL84 SET / KLIPSCH RP160M is such a good match as I know that like the SE-OTL, your SET reduces power into lower impedances - and the KLIPSCH RP160M presents a formidable 4-Ohm load for such a small engine.

I guess the quality of your SET Output Transformer makes the difference.

I've got to tell you that in its power-band - a VERY big disclaimer - the SE-OTL is probably the greatest amplifier I have ever encountered. It has an openness and dynamic directness that is very hard to find elsewhere.

I just couldn't manage the 100dB / 16-Ohm horn loudspeakers it needed to sing. I had to eventually let it go.

Shame.


SE-OTL LP Cover Perspective.jpg

SE-OTL Night Glow.JPG
 
With all "tiny " class A amps, the quality of the output transformer has the biggest influence on the sound. In very broad general terms, the bigger the transformer core, the better the results, providing the sectioning of the windings gets proper attention.
You also need a pretty clean power supply so they dont forget the lyrics and hum along.

Single ended transformers can be very tricky to get exactly right, and then may not suit "choob rolling ".
With larger triodes for instance, to get the absolute maximum performance, one might need buy 30 valves to find two identical for stereo operation. Say 2A3, 6A3, 6B4 etc. They are directly heated and add the problem of hum if not very cleverly designed.
I have a very small amp, but its push pull, and for exactly that reason. The output transformer in push pull operation cancels a very large amount of problems experienced with SE operation.


Joe
The way hammond measures its output transformers is discussed, mine is Hammond 125CSE. My 1.5 watt amp provides delicious bass and pleasant treble. Try the Hammond 125 SE series and you will be surprised. Would have liked to buy a pair of Tango, Lux, Hashimoto, or some other exclusive brand, but thought I'd try Hammond's first..And I was very pleasantly surprised. Have built various SE amps with, among others, ECL86, 6V6, ECL82, EL34, and they sound the same...Lovely
 
I recently, finally, found a pair of speakers that I love for the CS300x here. Speakers if had in another system- the JBL L82 Classics. It was a bit of an accidental pairing made up of gear left over after assembling my other two systems. It’s a really nice pairing. I’m a bit surprised at how refined the result is.
 
“Mod” would be a good way to describe the whole setup. The Leben is in the cabinet. I also have the blue grilles, and swap them now and then. The speakers were bought during the first lockdown in 2020, while my wife and I were living in a small apartment between moves with “the good stuff” in storage. Well, the JBLs earned a position among the good stuff and now anchor the dining room setup, with the Leben and various other gear, playing music while I’m sitting at the table eating or attending to other hobbies. EAADBCFF-BCC9-4D24-854D-919244E64888.jpeg
 
I still have an itch for a nice, high-spec 6V6 SE amp... 😊
There's one right here on Hi Fi Haven. I've built it as a test amp so far and tried 3 different output transformer setups: Edcor, Musical Power Supplies and MPS with parallel feed. They all sounded good but the MPS versions are better than the Edcor. The OP of the thread


Have fun,
John
 
There's one right here on Hi Fi Haven. I've built it as a test amp so far and tried 3 different output transformer setups: Edcor, Musical Power Supplies and MPS with parallel feed. They all sounded good but the MPS versions are better than the Edcor. The OP of the thread


Have fun,
John

🙈🙉
Thanks for the heads-up, John.
 
Sorry, I didn't finish my sentence above. The OP of the thread used transformers from Greece that measured very well. Paul_b measured both the MPS and the Greek transformers and they all looked pretty good. I can say the MPS outputs sound very good and my measurements, somewhere around page 12 of the thread show them to be very good.
 
“Mod” would be a good way to describe the whole setup. The Leben is in the cabinet. I also have the blue grilles, and swap them now and then. The speakers were bought during the first lockdown in 2020, while my wife and I were living in a small apartment between moves with “the good stuff” in storage. Well, the JBLs earned a position among the good stuff and now anchor the dining room setup, with the Leben and various other gear, playing music while I’m sitting at the table eating or attending to other hobbies. View attachment 60593

Very cool, John.

And FUNKY! 😊
 
Very cool, John.

And FUNKY! 😊
I’m kind of sad about it as I like it better than the system in my office which gets a lot more listening time (Luxman/Dynaudio). But the speakers just work visually in this room. They get pulled out with better placement when I’m listening more intently.
 
This is a great question… And I too have a set of 6CL6 that I am hoping to drop-in to replace our very old - but still perfectly operational -JAN-6197 power tubes.

On their respective datasheets, the main difference I have spotted is:
6CL6 has a much higher PLATE RESISTANCE specification.
[6CL6 ra=0.15megOhm
versus
6197 ra=0.09megOhm]


My thinking is that because the LEBEN has been designed around the lower maximum plate resistance of the 6197, the 6CL6 should pose no problems - replacing the 6197 - in this regard.

One remaining outstanding question is:
Do the two tubes share the same level of Gain?
I have been unable to find this info.

Sounds like a question for the very expert @paul_b

Come-in Paul. Can you provide an expert opinion on this?

@paul_b
In addition to the 6197 and 6CL6, I have tried another power tube in my Leben cs 300F, the Tesla 6L43 tube which have been playing for the last two weeks.
 
In addition to the 6197 and 6CL6, I have tried another power tube in my Leben cs 300F, the Tesla 6L43 tube which have been playing for the last two weeks.

Can you share any thoughts on how the sound changes between the three tubes, if at all?

We have found the 6CL6 may have a bit more body than the JAN-6197, but it might be all in our minds. 😂

Still, we've been running the RCA-6CL6 tubes in our feisty little LEBEN CS-300F with nothing but great results!
 
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Can you share any thoughts on how the sound changes between the three tubes, if at all?

We have found the 6CL6 may have a bit more body than the JAN-6197, but it might be all in our minds. 😂

Still, we've been running the RCA-6CL6 tubes in our feisty little LEBEN CS-300F with nothing but great results!
I find it hard to compare sound after changing tubes, but maybe maybe i felt the sound to have a bit more depth, but it could be me whishing also.

Anyway it is fun to have a third option regarding power tubes now, even if the 6L43 seems quite uncommon compared to 6197/6CL6.
A bonus is that the 6L43 have openings in the plate so you see more glow which I think is nice.
 

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Anyways, for those of you who prefer to kick every dog and chase every rabbit, here is my (formal) review of the LEBEN...

REVIEW: LEBEN CS300F Integrated Amplifier

The (few) professional reviews I have read about this LEBEN model have been overwhelmingly positive, despite the fact that they all provided caveats of one type or another around "...within its power limitations" etc., etc.

These caveats arose only because none of those reviewers carefully matched the 15w LEBEN with a suitably efficient speaker. Not one. It seems that they just merrily hooked-up the CS300F to whatever transducers they had on the shelf at the time and gave it a go. A HARBETH here, a TRENNER & FRIEDL there; let's try a FRITZ... Talk about epic mismatches! And they wondered why the little LEBEN occasionally ran out of steam?

Nevertheless - rather tellingly - all the reviewers adored the CS300F for what it does so well - despite being totally mismatched on every date. All of which begs the question: How does the CS300F sound when the speaker match is ideal?

Matched with our KLIPSCH RP-160M, the LEBEN CS300F is a veritable powerhouse! This is an ideal partnership.

I'm not exaggerating when I state that with the 15w CS300F driving our 96dB speakers, its identical to taking an 87dB speaker - like a pair of brand-new pair of TRENNER & FRIEDL ART 2 (85dB, actually) - and driving them with a 480w solid state amp. Yes, the electrical "drive" calculation is more or less identical. Would anyone dare call that a potentially under-powered partnership? Would anyone really question whether there was enough power on tap? Of course not.

In this type of scenario, the CS300F becomes a vicious beast, straining to be unleashed! With headroom aplenty, inquiries as to the available power become totally irrelevant. The only question that remains is: What does this amp / speaker partnership sound like?

This environment is precisely how the LEBEN should be reviewed.

Under these idyllic conditions, I can tell you that the CS300F is no "pipe and slippers" polite little number. Quite the opposite is true, in fact. The LEBEN is big and ballsy; and busting to breakout!

The CS300F can rock out with the best of them. Demanding genres such as Hard Rock, Metal, Electronica and Dubstep are pumped out with alarming attack. Bass is full, tight and deeply extended and there's absolutely no polite, syrupy, treble roll-off. Tops are crystal clear and extended. Fenders crunch, analog synth textures grind, cymbals crash and shimmer; and it's all held together in total chaotic coherence.

Then in a blink - with a speedy change of program - the CS300F can gently immerse the listener in a pool of intimate and palpable lushness. SET-like, the CS300F delivers quiet music for quiet times, beautifully. The little LEBEN is a quick-change artist, delivering whatever it is that your source is serving up.

Believe it! The CS300F is a nasty, thrashing brute one minute, a fluffy, purring little kitty the next; and everything in-between.

Orchestral warhorses with Tchaikovsky in full cry? Bring it on! Classical, Chamber, Trios, Quartets and the like? Superbly rendered. Jazz? Oh yes, Jazz! The CS300F loves Jazz and you can truly hear which artists have "got it" and which ones ain't. Reggae, Prog Rock, Military, Folk, it's Saul Goodman! Whatever the genre, with the little LEBEN, music is portrayed with all the sparkle, colour and vividness of a live event.

There are several worthy sonic constants (read constants - not constraints!) that permanently reside in the CS300F sonic palate. These include: -

Stunning dynamics! Even at low-level listening, the CS300F is fully loaded with the safety-catch off. Yes, the jump-factor can be quite startling. Massive dynamic shadings send transient snaps firing out of the speakers, like sonic missiles.

Truth of timber is ever present. Vocals sound like flesh and blood. These are real people! Likewise, musical instruments. This is where pianos sound like pianos with felt hammers striking wires under tension. Where the (typically elusive) leading-edges of piano notes are portrayed in stark relief. Drum kits sound like hard wooden sticks striking taught animal skins - not like the sound of Dr. Martin shoes kicking-in some flimsy dunny-door! Fretless bass lines carry that real boogie factor. Brass instruments deliver that spitty, crackly, metallic blat that used to have kids like me following the Sally Bands around the streets each mid-December evening. These are real instruments and the CS300F never lets you forget it.

Imaging and soundstage are stable and sonic cues, a revelation. Granted these aspects strongly depend on the capability of the partnering source and speakers, but when the fit is right, the CS300F will show you precisely where everything was lurking on recording day. Often, this will include apparent venue cues that extend way beyond the confines of your own listening space. Whilst many of these spatial effects are now "created" in the studio [long after the band has headed off for a beer and a smoke...] early stereo recordings - such as the legendary RIVERSIDE Jazz catalog, where they just recorded what happened and put it straight onto the vinyl lathe - prove beyond doubt that such spatial aspects do exist on simple, unprocessed recordings. If it's there in the mix - no matter how it got there - the CS300F will expose it, as created; intended or otherwise.

I could go on and on - I've already gone on and on - but I'd like to leave you with one final set of thoughts.

There is one aspect, that the above ramblings have not been able to capture; and that is the utterly unique "tube" sound. To my ears, tube sound is totally distinct due to the following three attributes.

Firstly, almost all tube amps deliver an accurately dense harmonic saturation of the (critical) mid-range and upper bass, which causes music to sound natural. Best revealed in the human voice, you know it when you hear it. It's the sound of flesh; living, breathing, swallowing and singing - complete with all the rich resinous tones that make the human voice, flutes, clarinets, French horns, trombones, cellos, violins and guitars so unbearably beautiful. The LEBEN CS300F conveys this midrange harmonic saturation in just the right dose, at least the right dose for our tastes.

Secondly, by virtue of their inherent design, all tube amps - even lesser designs - deliver a continuous flow of signal. The sound of this flow is very hard to describe - but easy to hear in the music generated. It's the reason why Grandad's old valve radiogram sounded so magical, all those years ago! Tubes allow the signal to gain (voltage, amplitude – as the design requires) as electrons magically leap through a heated vacuum, in a constant, unbroken flow. There is no switching on and off. There is no frequency. There is just a continuous flow of signal. The beautifully unbroken music flow that results, clearly reveals this miraculous gain process, to my ears and (evidently) to the ears of every staunch tube amp enthusiast. Every other amplifier technology (excepting transformer-only amps. Another story, another time...) uses ultra-high-speed switching (on and off hundreds of times per millisecond) to achieve their required gain. In those amplifier designs, the precious music signal is sliced and diced in the same way that digital processes sample only a portion of the full sinewave of analog recordings, in order to transfer the music onto CDs. Sadly, the human ear can hear the difference. This switching is not good. Tube amps don't do this. Tube amps are good; and the LEBEN CS300F is one of the best.

Thirdly and finally, tube amplifiers tend to present the sound of spatiality differently to other amplifier topologies. Whilst alternative designs can match or occasionally surpass tube amps in the left to right rendering of space, tube amps go the extra mile in the realistic portrayal of front to rear soundstage. This creates space - or at least, the sound of space. With good tube amps, recording venues can sound absolutely cavernous and everything sounds just a little bit more stereo; a bit more 3D. Everything is just a bit more palpable and in focus. With the LEBEN CS300F, you just want to reach out and touch it, the illusion so darned complete.

Be sure to give the little LEBEN CS300F a good, long listen. Partnered with the right speakers, I suspect it might be an end-game amplifier for many, as it was for us.

In any event, enjoy the journey - and please share thoughts on your listening experiences with the fiesty little LEBEN CS300F.

View attachment 15808
Beautiful pictures. Uses KLIPSCH RP-160M in my stereo system. I use an el 84 se, triode connected. maybe 1.5 watts, class A. Enough power to fill my living room with quality sound. Using a Thorens 321, connected to a diy EAR 834, and a Cambridge cd drive CXC and a Topping D70S
 

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I still have an itch for a nice, high-spec 6V6 SE amp... 😊
Just finished building a 6V6 SE, The Lacewood amp 2.0, with Edcor OT. Maybe plays louder than my el84 se triode connected, but my el 84 se has Hammond 125SE output transformers, and the bass is deeper, the mids more natural, and the treble is exactly where it should be. The Lacewood amp is not a bad amp!, but it's just that my el 84 SE, triode coupled has more...soul? There is, or has been, a discussion on another forum where the old tube boys say Hammond's data on the 125SE is wrong! Some of them have spoken to Hammond, saying the values are wrong, but they won't listen! The values or frequencies are not correct. When I play music that has bass, my Klipsch goes way down in the bass, way deeper than the 100 Hz that Hammond wants it to go. Here are "The Blue One", &V& SE, The Lacewood 6V6 SE 2.0
 

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There is, or has been, a discussion on another forum where the old tube boys say Hammond's data on the 125SE is wrong! Some of them have spoken to Hammond, saying the values are wrong, but they won't listen!
This is correct. Hammond doesn't understand what source impedance means and doesn't seem interested in fixing their issues. Lundahl wouldn't be a bad place to look for nicer iron that isn't insanely expensive.
 
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