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105/3's refurbished by me and now up and running
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zaktech
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PostPosted: Wed Oct 10, 2012 11:47 am    Post subject: Reply with quote

Krell clip? Please explain.. I'm not even familiar with the term clipping, but I see it mentioned often. I notice the 400xi speaker outputs are fused :~
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audiolabtower
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PostPosted: Wed Oct 10, 2012 1:02 pm    Post subject: Reply with quote

Clipping is where you drive the amplifier voltage output beyond the power supply rails so the top of the "curved" output waveform is flattened off to a straight line. Depending on the type and design of amp this can lead to instability and distortion harmonics which can heat up tweeters fast and be dangerous to their health. The converse is current limiting where you have enough voltage swing but the amp runs out of current into low impedance loads and protection circuits may introduce distortion.

I don't think you have to worry about either with your Krells, particularly not with a high sensitivity 105/3 at 93 dB/W.
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proffski
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PostPosted: Wed Oct 10, 2012 1:10 pm    Post subject: Reply with quote

Spot on and you beat me to it!
Busy building a UV TEA laser at the moment and you cannot keep the bods waiting!
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clubsport911
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PostPosted: Wed Oct 10, 2012 1:57 pm    Post subject: Reply with quote

OFF TOPIC ALERT... Who remembers "soft clipping" ? I recall a test report from a HiFi mag a few hundred years ago where the NAD 3020 - 25wpc - was able to demonstrate 192w into 2ohms (funny how some facts never leave your mind).
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proffski
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PostPosted: Wed Oct 10, 2012 2:49 pm    Post subject: Reply with quote

OMG an Off Topic Heretic! Shocked
I do not know why but I never liked the sound of NAD gear, this persists to today... never reasoned as to why.
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audiolabtower
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PostPosted: Wed Oct 10, 2012 8:03 pm    Post subject: Reply with quote

Yes, "soft-clipping" can be implemented by circuit design to "round-off" clipped waveforms and thus try and emulate a kind of 'valve sound'. You can design in a measure of second harmonic distortion to try and ladle it on too. Smile

I assume that 192W was for a millisecond? Laughing 'cos that would be nearly 10A through 2N3055s which were rated at 15A at low output voltage in those days if I remember correctly?
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proffski
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PostPosted: Wed Oct 10, 2012 8:30 pm    Post subject: Reply with quote

But I like the sound of valve equipment and even order harmonics in moderation of course, I just do not like the sound of NAD gear.
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clubsport911
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PostPosted: Wed Oct 10, 2012 10:17 pm    Post subject: Reply with quote

My goodness 2n3055's as used in (my older brothers) Leak Delta 70. Weren't there 2 versions of this transistor ? By any reckoning, they were a decent bjt as it happens...

Anyway, where is the off topic policeman ? Proffski, what do we do now ?
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proffski
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PostPosted: Wed Oct 10, 2012 10:30 pm    Post subject: Reply with quote

2N3055H was the higher power version, still use them at work for power supplies and other projects. MJ2955 was the PNP version, unaware of a high power variant. Neither renowned for respectable slew rates... Sad

2N3055H no longer made.
Delta 70 used two 2N3055s AC coupled output, yeuch!
Repaired too many in the past... the bridge recitifier diodes strapped to the transformer, eek!
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Last edited by proffski on Wed Oct 10, 2012 10:37 pm; edited 2 times in total
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proffski
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PostPosted: Wed Oct 10, 2012 10:33 pm    Post subject: Reply with quote

Now can we get back to the subject of 105.3s please? Very Happy
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clubsport911
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PostPosted: Wed Oct 10, 2012 10:41 pm    Post subject: Reply with quote

105.3's ?

Shurely Shome mishtake ?

Don't you mean 105/3's ? So as a matter of random interest, where did the "point three" suffix come from ?
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proffski
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PostPosted: Wed Oct 10, 2012 11:14 pm    Post subject: Reply with quote

clubsport911 wrote:
105.3's ?

Shurely Shome mishtake ?

Don't you mean 105/3's ? So as a matter of random interest, where did the "point three" suffix come from ?


I do not start drinking till Friday night. Smile
Name of this thread is: http://www.hifiloudspeakers.info/speakertalk/viewtopic.php?t=1369
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steve59
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PostPosted: Sun Mar 22, 2015 10:58 pm    Post subject: Reply with quote

Well I don't know what happened to the op but I want to second the suggestion to add the kube 200, audio,and stereo review both measured distortion from the addition but also added the "noise" only became relevant when the bass dial was turned up, I have it and I biamp with the dial on centered and appreciate the weight it adds, it still can't come close to the sheer output ov the 765's in the bass, but Kef was never about bass they are about making money getting the midrange right and not messing up the rest.
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steve59
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PostPosted: Mon Mar 30, 2015 1:59 am    Post subject: Reply with quote

I have a pair of 105/3 and 107/2 loudspeakers in the basement and believe it or not the combination of gear i'm listening to my 105/3's are out performing the 107/2's in the bass, the weight, sound, speed, clarity, every sense it shocked me so much I opened up all 4 boxes to make sure everything was a ok and my only explination I have is the 105/3 mates better with my gear than the 107/2. I miss the krell kav 300il driving the top end though.
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