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Old 29th March 2014, 10:04 AM   #12401
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Originally Posted by pellesmil View Post
Thanx

Yes i love my WTT, some dont like the lack of a lift but after some training i find the way of operating the arm much more comfortable and secure (even after a few single malts)

My WTT is the Record player witch is the least expensive i believe the more expensive have more arm adjustments.

Possible upgrades will probably be be motor related.
This "beginner" WTT is great as well and worth to upgrade it. I used 3 spikes as "feets" and a granite base plate - sounds wonderful. For the motor I'd try a small DC-Motor from Premotec :: Premotec :: Precision Motor Technology B.V. :: Your ideal partner for total drive solutions ::
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Old 29th March 2014, 11:52 AM   #12402
AndrewT is offline AndrewT  Scotland
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Originally Posted by pellesmil View Post
Could be,

But when testing out different transformer solutions and mains cables earlyer i found that the bass changed (got better) with better mains for the transformers.

I tryed to replace the 300VA R-cores in my BIII dac with the Shielded Torroids and the difference was not huge,
Could possibly had been some better resolution (hard to say) but i recognized the hump in the bass.

Thats when i tried to change to a better (audio) outlet without a jumper in between found that the bass was shaping up.

What i now hear now could be a mix of many: different load, less "micro-phonics" due to less vibration, better mains and shielded mains cable
Now that you know that Low Loop Area in your cabling is paramount to realising the performance of the system, do you think that putting the Rcore in, instead of the Toroid, will change the performance?
For the better, or for the worse, or identical?
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Old 29th March 2014, 05:14 PM   #12403
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Default No, experience with current phono stage

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Originally Posted by Salas View Post
Are you in FSP test phase already?
Amazing how collecting parts and inserting them into the boards is the easy part.

Always takes longer to get the enclosures and the wiring finished than one wants to remember from the last project.

Don't want to screw it up so trying to be methodical. Never have built a semiconductor amp before so I am nervous about destroying those rare FETs.
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Old 30th March 2014, 01:37 AM   #12404
Salas is offline Salas  Greece
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They aren't that flimsy if you will not overwork them. Use up to 25W wall iron or a controlled station at 360C with eutectic solder.
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Old 30th March 2014, 09:08 PM   #12405
RCruz is offline RCruz  Switzerland
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Originally Posted by Salas View Post
No, the sinks will saturate. They are small for hot rod.
I will use bigger sinks. Can I use the BiB calculator to determine the correct resistor value for higher current ?
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Old 30th March 2014, 09:49 PM   #12406
Salas is offline Salas  Greece
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For three red Leds calc setting it should be compatible. The 369s don't like large ambient delta in their box, mind you.
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Old 31st March 2014, 07:52 PM   #12407
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Default Not afraid to solder them!

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Originally Posted by Salas View Post
They aren't that flimsy if you will not overwork them. Use up to 25W wall iron or a controlled station at 360C with eutectic solder.
Just don't want to blow them up with improper final wiring/assembly.

Boards are complete. It is simply the wiring and enclosures.

I was alluding to the time I have ALREADY spent!

I am making my enclosure more complicated than is necessary. I am using Dave Slagle's autoformer attenuators at the output and those large caps require more space so my enclosure is growing.

I am hoping the phono stage will drive my 10K ohm impedance amplifiers along with a 40K impedance line stage for frequencies below 500 hz. Need the gain below to match the higher efficiency drivers above.

Made with a mixture of cedar and balsa - lots of gluing. This box will sit upon an HAMMOND seven inches square box for the transformers and rectifier board. If I have any noise problem I have some TIShield laying around though I do not want to use it. Hope there is no need.

I have found the heatsinks included do not readily fit on the input FETs. Had to "open" them up a little. Are you using any paste for these? I have not but started to wonder ... Any need for any additional heat sinks for the small FETs?

BEFORE THE MONTH OF APRIL COMES TO AN END - I will have this completed and IF I don't I hope you will scold me. I will deserve it!
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Old 31st March 2014, 07:57 PM   #12408
Turbon is offline Turbon  Sweden
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Quote:
Originally Posted by Salas View Post
For three red Leds calc setting it should be compatible. The 369s don't like large ambient delta in their box, mind you.
Use a mesh as top of the Box
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Old 31st March 2014, 08:08 PM   #12409
Salas is offline Salas  Greece
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@ Rick

-The third stage in the FSP is an AC coupled B1 like buffer, has about 60 Ohm output impedance and it can source up to IDSS current. I hope it will suffice in your system. You got to check that its C value regarding output coupling is good down to 10Hz at least with the line impedance you plan.
-Yes, those minisinks need some pre-formation to fit the TO-92s indeed. Maybe they make them like that to surely fit snugly. Paste, no, not really. The JFETs are not going really hot, its we saw that the mini-sinks keep them more controlled regarding self current drift. Make their cold to warm distance shorter. Useful in the double and single JFET input MC configurations only. But not absolutely necessary.
-Alright, take your time, we hope to see nice pics from your highly customized TT and phono when ready.
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Old 1st April 2014, 01:14 AM   #12410
nezbleu is offline nezbleu  Canada
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Quote:
Originally Posted by rickmcinnis View Post
Amazing how collecting parts and inserting them into the boards is the easy part.

Always takes longer to get the enclosures and the wiring finished than one wants to remember from the last project.
Amen brother!

I enjoy stuffing boards and soldering. Case work is the hard part for sure. Layout, drilling, wiring, etc. Always harder than I remember. Also a lot of time spent thinking about how to get from here to there, the best way vs the most practical way. Silly things like "Do I have enough of those screws? Can I get more locally? Why didn't I order more of those?"

Enjoy!
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