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Old 19th February 2012, 04:56 PM   #431
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Peter, What can I say! I have to try this myself. I wondered about carbon-composition resistors, maybe 10x 8,2R (0,5W) parallel for 0,82. what do you think?

Thanks for letting us know about these excellent developments!
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Old 19th February 2012, 07:19 PM   #432
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Originally Posted by vgeorge View Post
Dear Petavgeris,

a picture of your mods would be nice, especially how you did the graphite rod.
I have not available the cord of my digital camera and I cannot upload a pic. The rod is taken out of a Duellund resistor, it is around 3mm, but you can use a 2mm rod. Some mechanical pencils are equipped with this kind of rod.

The improvement in sound quality is so big that is hard to believe! At least in my system. I was never prepared for this kind of shock!
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Old 19th February 2012, 07:21 PM   #433
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Thanks,
maybe will try it soon.
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Old 19th February 2012, 08:02 PM   #434
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here some info GRAPHITE RESISTORS
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Old 19th February 2012, 09:52 PM   #435
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Very nice link!
Thanks a lot!

As soon as somebody here makes this mod, I would be thankful if we exchanged some ideas.

Regards from Athens.
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Old 19th February 2012, 10:02 PM   #436
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Originally Posted by Rod Coleman View Post
Peter, What can I say! I have to try this myself. I wondered about carbon-composition resistors, maybe 10x 8,2R (0,5W) parallel for 0,82. what do you think?

Thanks for letting us know about these excellent developments!
Rod,
carbon comp resistors do not sound that good like carbon/graphite resistors. The mechanism of resistance generation in various materials os totally different. For audio signals, you should look nowhere except carbon film or graphite resistors. For frequencies in magnitude of MHz they produce excessive noise and are not suitable.
Metal film resistors is a real disaster for music. Like plastic caps. These all sound terrible.
Replace ALL metal film resistors in your regulator, I mean everything! Use nice and cheap carbon films and you will see... Regarding the caps, Vitamin Q and russian K40-Y9 are the best. And do not forget to get rid of this crap of metal in R1, it takes half of the sound!
I have experimented with everything I could imagine, regarding DHT heating, I heard better things with your regulator but it did not make me fly. As soon as I replaced the cap and the R1 crap my mind and soul flew away.
Today I plugged my RV258 Telefunken oldies and I have to admit that Rod's circuit drew me inside the performance of these fantastic tubes as I have never felt before.

I have to give Rod my congratulations once again. The performance with graphite rod and Vitamin Q cap makes your soul fly to paradise! Trust me!
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Old 19th February 2012, 10:32 PM   #437
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will be good if we can found a big size graphite rod for diy resitor to k ohm...

I have used duelend one for scanspeak 9800 tw but haven't found nothing special...adding in series to duelund a small kiwane sound fantastic go figure

max watt dissipation ?
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Old 20th February 2012, 02:36 AM   #438
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GRAPHITE STIRRING RODS MELTING MIXING GOLD 5/16 2PCS | eBay

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Old 20th February 2012, 07:17 AM   #439
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Nicoch58
IME the graphite rod resistor is no better or worse than a MOX resistor. I believe the placebo effect does its job here... The more money or time we spend on so called improvements or tweaks the greater things we hear...

Try this: listen to the first 15 seconds of a track three times. Did you notice exact the same things in this record? Nope... The 3rd time is best due to our lack of good acoustic memory...

Back to topic. It takes a very good DHT regulator to outperform ac supply. I've done experiments with classic and exotic 3-pins voltage regulators and they suck the life out of music. I'll try tentlabs DHT supply in the future. Rods solution looks nice too!!
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Old 20th February 2012, 07:25 AM   #440
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Nicoch58
IME the graphite rod resistor is no better or worse than a MOX resistor. I believe the placebo effect does its job here... The more money or time we spend on so called improvements or tweaks the greater things we hear...

Try this: listen to the first 15 seconds of a track three times. Did you notice exact the same things in this record? Nope... The 3rd time is best due to our lack of good acoustic memory...

Back to topic. It takes a very good DHT regulator to outperform ac supply. I've done experiments with classic and exotic 3-pins voltage regulators and they suck the life out of music. I'll try tentlabs DHT supply in the future. Rods solution looks nice too!!
You're right about the 3-pin regulators - they are useless for filament heating. But ac-heating is also bad-sounding, compared to the possibilities of Direct-Heated Triodes.
The first test to make with a filament regulator is to compare to ac. If your new regulator does not sound better in every possible way than ac, then you have a failure.
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