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Old 28th March 2007, 07:46 PM   #161
steenoe is offline steenoe  Denmark
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Quote:
...I am quite surprised! I had my money on your being first Steen! Are you feeling OK?
cviller is cheating
Dont worry, I am adjusting mine right now Both channels started up like a dream I am really looking forward to give it a good listening session this weekend.

Steen
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Old 28th March 2007, 08:05 PM   #162
cviller is offline cviller  Denmark
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Quote:
Originally posted by steenoe
cviller is cheating
You got me! Photos are manipulated - I have been lying on the couch watching discovery all the time!!!
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Old 28th March 2007, 08:19 PM   #163
steenoe is offline steenoe  Denmark
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I am cheating too I stripped out my Aleph 5 and popped in the F4 Have a look. In case some of you with keen eyes are wondering; no the faceplate is not yet mounted

Steen
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Old 28th March 2007, 08:37 PM   #164
cviller is offline cviller  Denmark
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Nice!!
I can see you found good use for the mounting holes! You have to listen to it soon...
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Old 28th March 2007, 10:01 PM   #165
Magura is offline Magura  Denmark
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Quote:
Originally posted by steenoe

I am cheating too I stripped out my Aleph 5 and popped in the F4 Have a look. In case some of you with keen eyes are wondering; no the faceplate is not yet mounted

Steen

Nice clean work as always Steen

Magura
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Old 29th March 2007, 02:39 PM   #166
Formerly "jh6you". R.I.P.
 
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~oo~


Papa,

I was having coffee break, once again looking at F4 schematic.
Ahh . . . almost dropped the coffee mug.
My body started sweating cold drops . . .
I was really scared by your mysterious smile hidden behind the
voltage swing at the input.

How many more do you have scary things ^^?


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Old 29th March 2007, 06:09 PM   #167
steenoe is offline steenoe  Denmark
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Quote:
My body started sweating cold drops . . .
You can start sweating the hot ones I have been listening to the F4 all afternoon and man, does it sound great. I am stunned and (nearly) speechless Its a most jawdropping experience, listening to the F4. I have no idea how Mr. Pass does it, but this amp has just turned my world, upside down! I am not kidding
Here you go:Speakers are ProAc Response 2.5 clones, rating in at 86-87 dB sensitivity, so pretty much on the borderline!! First I tried it with the X-BosoZ but it was way too whimpy. Sounding great, it couldnt get any reasonable soundlevel from the F4. I blame it on using the X-Bos singleended out! Installing the Threshold NS10, made things a lot better. The NS10 can drive the F4 to nearly max output. The NS10 is pretty brutal, as you might know. Still, it cant drive the ProAc's to full output, using the F4. At full throttle, the sound is still very pleasant!!
Here is an account on the sound: The bottomend is very firm and very deep, pretty much the best I've heard. Voices are present and precise like never before and the topend is really stretched out and detailed. I think the F4 put on, at least 2 octaves in the topend, being very detailed and pleasant to listen to, at that.
The soundstage is huge, tremendously wide and deep. All instruments and voices are clearly cut out, in the overall "picture"!
The "sweet spot" seems to have widened too, with the F4. One doesnt have to be bang on the spot, as much as we are used to.
I am sure everyone listening to my system right now, would agree! I will absolutely build these as monoblocks and drive them balanced. The great thing is that I can use the PSU and chassis's from my A-X's I am sure the F4 will benefit even more from a huge PSU made up by big Rifa's and Magura's inductors This was just a fast build to see if the "rumours" were true Thanks a lot Mr Pass for this magnificent amplifier! Thanks to cviller for a genious board layout!

Steen (very impressed, indeed)
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Old 29th March 2007, 06:24 PM   #168
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Steen

Great to hear that your F4 sounds so magnificent, you steer my desire.

What rail voltage are you using?

I know that these are apple and pears regarding a comparison with your AX but would be interesting to hear your comments soundwise.
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Old 29th March 2007, 06:26 PM   #169
cviller is offline cviller  Denmark
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Great you finally carried the it the 10 meters into your living room!

I'm happy to hear you like the sound so much - great info on the preamp! I guess my preamp only drives it to 25% or so, but I'll agree with you that it sounds very nice indeed!

Are you running it with 250mV across resistors? Mine had very noticeable distortion at 80mV, but 300mV is too much for the box I have mounted it in right now.
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Old 29th March 2007, 06:43 PM   #170
steenoe is offline steenoe  Denmark
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Hi Tony I am using 2, 300VA trafos with 2x18V secondaries.
The rails run at about 22V DC, but I didnt take an excact reading.
Its all about apples and pears, allright, but I have no doubt, the F4 is the best sounding amp, that I have ever made/heard! My A-X's are about to be under heavy modification The A-X's might be almost as good in the bottom, but the middle and topend register is much better with the F4! When I first sat down and listened, carefully, I first thought: whats that trembling noise?? I then realised it was the drummers slight touches on the brass's!!
Thats how amazing the F4 is! Drop all your other projects, and go straight to the F4! Beleive me, you wont regret it

Steen
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