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Old 4th October 2011, 04:26 PM   #31
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The brand does not matter.
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Old 8th October 2011, 12:43 PM   #32
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Building a battery P.S. should not be a big deal for a preamp, but I had not been convinced by the approach. ..15 years ago when I lessoned to a high end battery powered preamp.
I am not sure of the model, I believe it was a Jeff Rowland or something like that, and I had not been so much impressed.
So I will maybe try this, but I do not expect a so big improvement... Contrarily, I have been, for sure, incredibly impressed by the power supply upgrade described on my website.
Since I have completed this AC power supply upgrade, I believe that the P.S is a totally under estimated part in the preamps/amps, even in the high end devices, where it is still possible to get a huge improvement.
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Old 8th October 2011, 05:01 PM   #33
GaryB is offline GaryB  United States
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Originally Posted by Nounours18200 View Post
Building a battery P.S. should not be a big deal . . .
So I will maybe try this, but I do not expect a so big improvement...
Nounours,
I look forward to your experiments in this regard. Your experience upgrading your 10e seems to match mine, so I'd be very interested the results if you have time to experiment with battery supplies.

By the way, I think it's time for me to replace the volume/balance control in my 10e. I thought the preamp was sounding good but I did a quick experiment that tells me there is still a lot of room for improvement. I swapped out the 10e for a passive preamp using optocouplers. It's based on the Warpspeed modules that Blues mentioned in post #3. While I still think that an active preamp has a drive that passive preamps miss, there is no question that the optocoupler passive preamp had much greater transparency and detail. So I'm going to try putting better volume controls in the Threshold. And I'll add a buffer to the Warpspeed - perhaps that will give the best of both worlds.

---Gary
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Old 8th October 2011, 05:59 PM   #34
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Please explain how a battery can be beat.I just dont see how!
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Old 8th October 2011, 11:03 PM   #35
GaryB is offline GaryB  United States
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Originally Posted by bigfishe View Post
Please explain how a battery can be beat.I just dont see how!
Steve,
You might want to think a bit about the impedance of your power supply as a function of frequency. Ideally your power supply will look like AC ground at all frequencies. If you look on the web you can find articles where this has been measured. For example - http://www.telepower.com.au/INT95b.PDF
Clearly batteries are not perfect and you'll still need to do some work to wring out the best sound.

Batteries have advantages in not being connected to the AC lines, which tend to be noisy. But they're not a panacea. And they have their own maintenance and charging headaches, which turn some of us off.

There are many roads to audio nirvana. I'm glad you've found one that you like. Humor the rest of us who chose another route.

---Gary
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Old 9th October 2011, 08:59 PM   #36
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Quote:
By the way, I think it's time for me to replace the volume/balance control in my 10e. I thought the preamp was sounding good but I did a quick experiment that tells me there is still a lot of room for improvement. I swapped out the 10e for a passive preamp using optocouplers. It's based on the Warpspeed modules that Blues mentioned in post #3. While I still think that an active preamp has a drive that passive preamps miss, there is no question that the optocoupler passive preamp had much greater transparency and detail. So I'm going to try putting better volume controls in the Threshold. And I'll add a buffer to the Warpspeed - perhaps that will give the best of both worlds.
Gary: just read again the article on my website: I have already replaced the volume control by attenuators. I strongly encourage you to do the same! After having upgraded the Power Supply, replacing the volume control by attenuator is a must have!
The Fet-10 goes to another level of excellence, details and transparency.

I have spent a lot of time to identify which attenuator I should use, both to reach the best possible sound and also to have enough space to locate it into the (small) cabinet.
As indicated in the article, I have chosen the GOLDPOINT Mini-V because:
-they are as good (if not better) than the Dact ones
-they are available in 25kohm impedance, whereas the dact only exist in 20kohm...
-the other brands are usually bigger, so they cannot be located in the cabinet.

With the GOLDPOINT mini-V, you can choose TWO mono 25kohm attenuators, and they can easily be installed in the cabinet: you just have to remove the balance control (I personnaly never use it) and you just have to slightly enlarge the axis holes on the front plate of the Fet-10, because the Goldpoint have a slightly bigger axis than the original NOBLE potentiometers.

Just refer to the Thresholdlovers article or just ask me if you have questions,
All the best,
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Old 23rd October 2011, 07:30 AM   #37
Lavcat is offline Lavcat  United States
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Originally Posted by GaryB View Post
1/16" allen wrench is the size you want. In a pinch you can use a 1.5mm wrench - it's a bit undersized but will work.

---Gary
Thanks. Having now obtained a proper 1/16 inch allen wrench, 1/16 inch is clearly the right size tool. But unfortunately I still can't get the screws out. I have the feeling the designer never intended the FET ten to be taken apart.
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Old 23rd October 2011, 06:22 PM   #38
GaryB is offline GaryB  United States
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Originally Posted by Lavcat View Post
. . . I still can't get the screws out. I have the feeling the designer never intended the FET ten to be taken apart.
I can assure from personal experience that it's not hard to remove the screws if you've got the right tools. Have you stripped the screw head by any chance? This would be the case if the allen wrench just rotates and doesn't grip the screw. Fixing this is a bit tricky since you'd need to get a screw extractor. I measured the diameter of the screw threads and it's ~ 3/32", so you'd need an extractor that works with screws that small.
If the screw isn't stripped then you just need to use a bit of force to loosen the screw. They're torqued down and do require a bit of force to get started. After that they come out easily.

---Gary
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Old 23rd October 2011, 06:42 PM   #39
Lavcat is offline Lavcat  United States
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Originally Posted by GaryB View Post
If the screw isn't stripped then you just need to use a bit of force to loosen the screw. They're torqued down and do require a bit of force to get started. After that they come out easily.

---Gary

It's possible I may have stripped one. The others seem intractable. Will try again this afternoon and report back.
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Old 23rd October 2011, 08:16 PM   #40
Lavcat is offline Lavcat  United States
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I was able to remove one screw. The tool I am using is 38603 - Bondhus 38603, 1/16 GoldGuard Plated Balldriver Screwdriver (2)

Perhaps an 'L' shaped hex wrench would be better? What I wish I had was a tool with a thick shaft and a large handle, but I've not been able to find any such thing. The tool I have feels like it is going to snap the shaft before the screws come loose.
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