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PostPosted: 18 Feb 2011, 07:27 
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Joined: 06 Jun 2008, 18:23
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Location: Australia
This one (thread) has to get through the moderators. It runs very close to the BHL Le Pacific and Mongrel Dog Audio derivities but after much intra-spective soul searching and gnereal 'net bashing I believe it should have its own thread.

I would not like to see this thread polluted by too much rant-n-rave about other Le Pacific clones. We have threads for that. Let's keep this one fresh and true to Le Pacific originals.

http://randytsuch-audio.blogspot.com/20 ... stage.html
http://www.vinylengine.com/phpBB2/viewtopic.php?t=16662

Above are just a couple of links which hone right into the Le Pacific culture.

"What's the Dog got in his mouth?"

A good friend of mine, Paul, who will remain nameless, built a "lucy" Le Pacific (see links above). Paul had a lot of problems with his original build of the phono preamp but eventually got it setteled and was was enjoyed at AmpFestDownUnder 2010 (see other threads on this forum).

It is my intention to build a "Lucy" Le Pacific in true "Dog" style and compare it to the latest boozhoundlabs Le Pacific phono preamp I built (and will be on ths forum) a few weeks ago. I hope to have it complete annd playing in the next few weeks.

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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 21 Feb 2011, 12:58 
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Location: Dartmouth, Nova Scotia
This looks like yet another interesting mosfet phono stage, do you think 2SK246 will work in place of the 2SK170? Not low noise devices like the 2SK170, but they are rated at 50V, not an advantage in a phono preamp though.

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PostPosted: 21 Feb 2011, 15:49 
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I just have to build it to see how is compares with all that has gone before it. I use the 2SK170s because I bought 50 of them at 50cents each. So it would be silly to use anything else. And the low noise aspect of this device is a big plus in phono stage. I can't see that the Le Pacific will be better than the BHL kit. Though I have been listening to the finsihed kit now for a few weeks I still feel it is improving.

Tonight I get a chance to play it for about three hours non-stop. I just bought some more Opera box sets and tronight: Madam Butterfly from 1958! Decca recording and on a short listen, promises to be very good.

What I do remember about the Le Pacific original I did listen to a few weeks back is that it was bright in the upper-mids to treble. It did sound excellent and that's why I'm going to try one. The BHL kit is darker in the mids and smoother out to the upper register. But this preamp takes many hours of play to settle in. When I first played it I thought is sounded awfull but within a few hours it started to perform better.

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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 22 Dec 2011, 21:59 
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A tubecad two stage phono preamp I built for a friend with an MC cart. does not have enough gain. I am part way through building him the Le Pacific pre-pre for MCs. So far the cast Al metal enclosure is drilled and primed. Now for the cct. brd. It will be powered by 8 X 1.5V AAA batteries also in the case. Because there is only a single jFET per channel and a few resistors everything should fit in the small case. Should have some images by tonight.

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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 23 Dec 2011, 02:10 
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Progress so far: cct. brd. is done apart from some wires to connect to RCAs etc. Case is top-coated and in a few days ready for assembly. No it is not yellow it is Sungold. As usual I left little room to install components by putting the battery pack on the cct. brd. I had to use Russian PIO 0.47uf caps for the output (smaller caps would have made the job easier but I wanted a good sound). I added 220uf low ESR cap to sit across B+ (12V) and a 0.1uf snubber.
Attachment:
Case.jpg
Attachment:
CCtBrd.jpg
Attachment:
CCTBrd_II.jpg
Attachment:
CCtBrd_III.jpg


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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 26 Dec 2011, 21:17 
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Finally finished the Le Pacific pre-pre for MC. It worked first time no oscillation, hum and noise. Once again I chose too smaller case and final assembly was painful. But it works and battery changes are easy. I purchased a new MC Crypt TT (made by Audio-technica I think) and a Audio-technica AT-F3/III MC cartridge. The TT is direct drive and a dream to use with removable head shells. I got an extra cartridge and head shell. This pre-pre is to go with the tubecad tube phono preamp posted on another thread.
Attachment:
InCaseII.jpg
Attachment:
CasedI.jpg
Attachment:
CasedII.jpg
Attachment:
CasedIII.jpg
Attachment:
TT2.jpg


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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 27 Dec 2011, 01:39 
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Running anything on batteries there is always the concern for time between replacements. AAA batteries have about a 1000mAh life. Each jFet draws 7.5mA for a total on 15mA. The blue led is fed by a 1M resistor so no need to count the drain here. For a total of 15mA draw I would expect better than 100 hours of play before battery changes or two to three months between changes.

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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 28 Dec 2011, 07:40 
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Location: Australia
I delivered the Le Pacific MC preamp to the guy who has my tubecad phono preamp today. It all worked perfectly, plenty of gain and a great sound overall.

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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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PostPosted: 30 Dec 2011, 13:37 
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Joined: 15 Aug 2011, 05:22
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Hi! Markhouston.. I prefer you to get a better Cap and Resistor

Like Nichicon Audio Grade,obbligato,DALE,Amastran or Allen Bradley... These part make your system got a better sound!


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PostPosted: 31 Dec 2011, 20:23 
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Added a LePacific MC pre-stage to my Boozhound labs jfet phono preamp kit. An extra pair of input RCAs allow two turntables to be connected. A switch selects which to use. The MC stage has its own battery pack which is switch on with the main power switch. I will add an isolation switch so that when the MC stage is not being used it can be turned off.

The MC stage works OK but with quite recording I have to turn up the volume and hum and noise can be heard. Also the new NcCrypt TT has rumble which can be heard when the volume is turned up.
Attachment:
LePacificMC.jpg
Attachment:
LePacificMC_I.jpg


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Projects: "Sanctum" - 12AU7 and 6AS7 direct coupled headphone amp | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "Mimic Carbon" - carbon resistors and PIO caps. MM phono preamp
Website: retro-thermionic


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