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Old 30th June 2013, 02:13 PM   #1711
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Quote:
Originally Posted by KASUMI View Post
Interesting juanitox ,where did you manage to get the PEH200's ?
The PEH169 also looks good
radiospare UK
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Old 30th June 2013, 03:33 PM   #1712
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Originally Posted by KASUMI View Post
Thank you KASUMI, I thought it would be an easier way...
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Old 4th July 2013, 07:32 PM   #1713
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Today I put the SIT on test......
The drain is 72V and the gate -12V, I am pulling 0.8A
So the dissopation is around 50W...
Everything looks good...only concern is the 50W rehostat which
is very very hot but it burns only 9.6W...
I am still waiting for the caps to arrive...
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Old 5th July 2013, 06:23 AM   #1714
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Red face Bypassed Source Res??

Quote:
Originally Posted by juanitox View Post
in fact with a SS preamp i prefer bypassed source resistor version and with a tube preamp with output coupling cap i can go with battery on source which i prefer to LM317 bias module.. but anyway this sit is a keeper .
potting the 193V is a cheap but fine upgrade
Hi Juanitox!

I tried the solution with the bypassed Source resistor - where I used a 10volt/0.22 Farad Nec capacitor. At the same time I changed the 47 ohm Gate resistor to a Amtrans(earlier it was Metal Film). And the soundstage grew somewhat bigger and a little more clear - BUT the voices and the music grew much too sharp, edgy and tonally very unpleasant. Nearly as sharp as when I tried a relatively middlepriced loudspeaker-cable.
I also use Amtrans in the signal-chain on my B1 Buffer. And I use Allen Bradley on the Sowther Trafo on the Direct SC3248Dac.

When I removed the Nec bypassed Cap, the edgyness disappeared and my Alp12P was back to that fine state of very transparent displaying of the musical content of everything I throw at the chain - and without my ears/wife being bothered with sharp sound and music.
So my experience is opposite to you - with my chain of electronics - Dac w/trafo and Carbon Resistor - B1 Buffer w/Carbon Res - LÀmp w/Carbon Res, AND no Bypassed Source Resistor. Clear and distinct sound with no edginess, and Solid State.
But to this I will add: I think I found a good speaker to make the Alp`s sing beatiful!

Best
Olav
Attached Images
File Type: jpg NEC condis.jpg (4.7 KB, 435 views)
File Type: jpg Amtrans res.jpg (17.9 KB, 423 views)
File Type: jpg L`SIT og Alp12P.jpg (58.0 KB, 419 views)
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Old 5th July 2013, 07:28 AM   #1715
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Red face Some missing words in post...

Hi all!

Some statement that was wrong in my last post - the last line should read: I think I found a really Good SpeakerCable to make the Alp12P sing beautiful with the L`Sit Amp!
And I have made the cable run straight to the driver - with no BindingPosts on the back of the speakers.

Best
Olav
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Old 5th July 2013, 03:33 PM   #1716
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What speaker cable is it?
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Old 5th July 2013, 03:35 PM   #1717
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hi olav, i have now a 26 DHT preamp with output cap and now use a 4V cell battery as Bias with my sitamp ... but from the time i used a bypass cap and douce resistor i didn't notice any hardness in the sounds but i was using a 47000uf mundorf mlytics in this place..
anyway you have a fantastic looking wooden case for your sitamp !!!
cheers

rohan
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Old 5th July 2013, 05:29 PM   #1718
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Arrow Yes Vdi_nenna and juanitox...

Hi both builders of fine audio gear....

I used the Nanotech(silver/gold layered) diy cable-kit from Jaguar-design, and it gave a very audible and warm displaying of the music when I changed from some self-made silvery/copper(also good) - bought from EBay! the silver could also sound some cold at times!

Yes Juanitox - my boxès for the SIT was nearly as ordered(they were made for 3 liter wine-box), and I fixed and strightened them somewhat so they could stand the 400 watt trafo + some electronic and such! Ended up stuffed - and I don`t want to show the inside - even if it is fairly orderly and safe - it is STUFFED. Some Heat-sink also.....

I think I will build a new pre-amp, so I have not moved the Nec-cap fully out(disconnected) - and will make a LDR - based pre-amp from Tortuga(probably) in the autumn. So I will try it again.
But the sound is again harmonius and revealing AND without the roughness that the Caps was displaying(or maybe they should have some more run-in time????)
But the sound with Carbon is my preferance on The Sowther Dac-The B1 an The L`Sit!

Best

Olav

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Old 10th July 2013, 08:45 AM   #1719
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Quote:
Originally Posted by OlavHaal View Post
Hi Juanitox!

I tried the solution with the bypassed Source resistor - where I used a 10volt/0.22 Farad Nec capacitor.........
these are "memory caps" , so - having sissy current capabilities , absolutely inadequate for task
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Old 10th July 2013, 04:16 PM   #1720
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Thumbs up Thanks Zen Mod...

Hi!

Had afeeling for just that - not exactly Audio Capacitors. I was just curious about the sound with these as they didn`t look to far off from what other used as bypass caps.

So I keep to my straight and simple solution as my Amplifier is today:
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