[Raaf]

The setup is OK but I don't like the carpet

 

[BugleBoy]

Quote:

Looks like Duelund capacitors, the big ones in the picture are very expensive!
 

Yeah...they cost over $400 a pop. They are arguably the best capacitors available at present.

 

[BugleBoy]

Quote:

That setup has really low WAF

 
The trick is to keep the room a bit untidy at all times...then this will just blend in

.

 

[longbowbbs]

Quote:

Quote:

That setup has really low WAF

 
The trick is to keep the room a bit untidy at all times...then this will just blend in

.

LOL!!  Camouflage, Nice!

 

[LarsHP]

It seems that the Prelude from Carmen is giving the CS300 some early distortion so to speak - that is - I can listen to other tracks louder without distortion. This is with HE-6 from headphone output. At the same volume dial position I also hear distortion on my speakers. In other words, it might have to do with a too high level at the input stage. (Maybe someone with better tech knowledge can correct me here?)
 
Today I mounted a couple of 10 Ohm power resistors in parallel on the speaker taps and attatched the HE-6 to those. Since the CS300 is 12W, the HE-6 receives up to 2W (and the resistor 10W). This way I have a much higher output available - higher than I need, but maybe not high enough to play distortion-free at profoundly ear damaging levels. In other words I feel I have enough power, but just so.
 
However, I now hear a little bit of humming between tracks (and when the music is very low level). This is allegedly fixed by mounting a choke (as Anders has claimed), but I won't do that myself ...
 
Treble is simply gorgeous and bass is tight and punchy. A very relaxed sound with lots of space around instruments.

 

[Raaf]

If it is only the Prelude from Carmen that gives distortion problems it might have to do with the "edgy" recording level of that track.
Perhaps some amps can just handle it and the leben just not .
I do recognize the problem , I have some (to) loud recordings al well.

 

[Anders]

Quote:

Today I mounted a couple of 10 Ohm power resistors in parallel on the speaker taps and attatched the HE-6 to those. Since the CS300 is 12W, the HE-6 receives up to 2W (and the resistor 10W). This way I have a much higher output available - higher than I need, but maybe not high enough to play distortion-free at profoundly ear damaging levels. In other words I feel I have enough power, but just so.
 

 
It you really want to destroy your ears you could try with 20 ohm resistors for higher output!
 
Congratulations to the improvements! I didn't say that a choke removes humming and only asked my tube guru about it and he said that it is a good idea and it reduces noise. I think that it was Raaf who had done it and reported positive results. I don't experience humming as a problem and have no plan of trying it for that reason, but maybe because of the general improvement of sound quality that is possible (noise leads to some loss of transparency).
 
However, the design goals of Mr.Hyodo seem not to be to minimize noise and get top results on standard measurements. Many also have observed that the relation between standard measurements and sound quality is weak. Indeed, some designs probably got worse sound as a consequence of reducing distortion to extremely low levels with lots of zeros before the significant digit (e.g. massive amount of negative feedback). Leben sounds like it sounds, IMHO not totally transparent and it rounds of a little and make the music a little more beautiful than it really is. But in a way that emphasize the essential musical content and is musically appealing and very listenable. Sometimes I use other amps for a change and a different take on the presentation.
 
I doubt that your source has too high output level and that this causes distortion. Of course, if it has much higher specified output than standard it is possible but it is unusual that components has that high output. In that case it can be solved by an attenuator between source and amp. That kind of distortion on a single or a few albums can be very difficult to track because there are so many possible causes.

 

[LarsHP]

Sorry about quoting the wrong person (to both Raaf and Anders).
 
I should add that I have checked used declipper on that specific track and also checked it afterwards in Audacity (zoomed in very close on the waveform), so I can see as well as hear, that there is no clipping. As I said this distortion only happens over a certain volume/level.
 
My issue with this amp right now is that I obviously have either hum and enough power - or no hum, but too little power. Could this be because the amp is 12W only? Or is it because it has a higher noise floor than I am used to from solid state amps? Or both? I am only guessing.

 

[Anders]

It certainly has a higher noise floor than modern SS amps.

 

[Raaf]

Lars, just put in a choke.
I am convinced you won't regret it , it really is a good improvement.
Chokes do not affect the sound in a negative way.
 
Before I placed the choke I tried all sorts of improvements like netfilters and even a net decoupling transformer for my dac and amp , but alltough that gave a very clean sound it allso cleaned out the soul of the music.
But do make sure it is a classic metal core choke and not some modern ferrite composition core choke, the last ones clean out to much.

 

[LarsHP]

Quote:

The only way I could get my CS300 completly silent was to put a choke in de powersupply for the driver tubes.

So, did this lower hum or hiss - or both?
I hear mostly hum, not hiss.
 
I did see your pic of the choke also, but could you possibly take a photo showing exactly where it is soldered in please?

Also: What value is it or needs it to be?
 
Edit: Just re-read your previous post and you already gave enough info about placing of the choke there ...

 

[LarsHP]

What about slightly turning the big / PSU trafo to see if the magnetic field will hit the input circuits less?
Someone suggested this to me, but I am a little hesitant becuase this implies the trafo has to be mounted in new holes in the metal plate and I prefer not to drill in it

 

[Raaf]

Quote:

What about slightly turning the big / PSU trafo to see if the magnetic field will hit the input circuits less?
Someone suggested this to me, but I am a little hesitant becuase this implies the trafo has to be mounted in new holes in the metal plate and I prefer not to drill in it

That would be much more work than putting in a choke, just think of all the connections you need to redo.
About the value of the choke, i used a old transformer so I have no clue but 2359glenn posted earlier :
Quote:

Here is a small choke at low cost that should fit.  It is sold at Allied Electronics.
I use these all the time.
I don't know why expensive amps like these have such a cheep power supply.
 
http://www.alliedelec.com/search/searchresults.aspx?dsNav=Ntkrimary|70218148|3|,Ny:True,Ro:0&dsDimensionSearch=D:70218148,Dxm:All,Dxp:3&SearchType=0&Term=70218148

Farnell sells these as well and even in your native language http://no.farnell.com/jsp/search/browse.jsp?N=2022+203354&Ntk=gensearch&Ntt=Triad+Magnetics&Ntx=mode+matchallpartial

 

[LarsHP]

So it needs to be able to handle the full 115V / 230V that we have from the wall outlet?
I also have some small wall wart PSU's lying around somewhere that I might be able to use ...

 

[Raaf]

That is what I used, 230V here in Netherlands