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Old 19th March 2013, 08:46 PM   #2591
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Quote:
Originally Posted by merlin el mago View Post
Just finished mine, tomorrow will be the great day to hear it, attached some pics just for fun. Finally and due to limited space inside the lineamp I used CCS+Gyrator courtesy of Ikoflexer also for same reason in place of Thomas Mayer TVCs I used a pot 100K log Noble, all RCA connectors are rodhium plated, all AC & DC connectors are Powercon & Speakcon, heaters regs are Rod Coleman used the chassis as heatsink, sockets are teflon Yamamoto, rectifier valve AZ1 and #26 are Cunningham waiting one globe Cunningham because one bought in ebay was spoilt it was not working the heaters. Waiting you will enjoy.
Very Nice Filipe,
I like the slim looks, and the aluminum mounts on the tubes bases!

What about the sound? Do you fill the tubes are microphonic?

Enjoy your build.
Cheers.
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Old 20th March 2013, 12:46 AM   #2592
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Quote:
Originally Posted by merlin el mago View Post
Just finished mine, tomorrow will be the great day to hear it, attached some pics just for fun. Finally and due to limited space inside the lineamp I used CCS+Gyrator courtesy of Ikoflexer also for same reason in place of Thomas Mayer TVCs I used a pot 100K log Noble, all RCA connectors are rodhium plated, all AC & DC connectors are Powercon & Speakcon, heaters regs are Rod Coleman used the chassis as heatsink, sockets are teflon Yamamoto, rectifier valve AZ1 and #26 are Cunningham waiting one globe Cunningham because one bought in ebay was spoilt it was not working the heaters. Waiting you will enjoy.
Nice!
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Old 20th March 2013, 01:29 PM   #2593
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Quote:
Originally Posted by rclourenco View Post
Very Nice Filipe,
I like the slim looks, and the aluminum mounts on the tubes bases!

What about the sound? Do you fill the tubes are microphonic?

Enjoy your build.
Cheers.
Quote:
Originally Posted by amandarae View Post
Nice!
Thank guys, before the hear the preamp I measured this morning feeding a sinus 1kHz and the result are not OK, attached pics, help will welcome.

TIA
Felipe
Attached Images
File Type: jpg DSC00257.jpg (567.7 KB, 172 views)
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File Type: jpg DSC00262.jpg (522.1 KB, 54 views)
File Type: jpg DSC00263.jpg (517.2 KB, 56 views)
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Old 20th March 2013, 02:47 PM   #2594
vgeorge is offline vgeorge  Greece
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What is the second and third pictures?
Also, better stay below 1,5V on the heaters.
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Old 20th March 2013, 02:59 PM   #2595
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1st pic is the sinusoidal measured directly by the scope. Second & third pictures are or better have to be 1Khz sinusoidal output left & right channel

Last edited by merlin el mago; 20th March 2013 at 03:04 PM.
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Old 20th March 2013, 03:16 PM   #2596
iko is offline iko  Canada
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Please post the schematic with all measurements that you make (voltage, current) on the schematic.
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Old 20th March 2013, 03:23 PM   #2597
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Schematic with measurements
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Old 20th March 2013, 03:25 PM   #2598
iko is offline iko  Canada
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You have both a gyrator AND an output transformer? Ouch! I'd use either the gyrator with the output provided via a 4-6uF capacitor, or the output transformer. But not both. If you keep the output transformer then you need to make sure the supply voltage is appropriate so you get the 150V on the 26 plate.
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Old 20th March 2013, 03:28 PM   #2599
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I need the OPT because power amps are SS.
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Old 20th March 2013, 03:47 PM   #2600
vgeorge is offline vgeorge  Greece
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Quote:
Originally Posted by merlin el mago View Post
1st pic is the sinusoidal measured directly by the scope. Second & third pictures are or better have to be 1Khz sinusoidal output left & right channel
Something is very wrong. Looks like serious oscillation. Be careful not to toast any tubes!
Listen to IKO.
I use the SSHV2 directly to the output transformer, and there is no problem.
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