Author Topic: Van Waarde inspired OTL headphone amp  (Read 11773 times)

Offline Rodney_gold

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Re: Van Waarde inspired OTL headphone amp
« Reply #15 on: December 20, 2010, 06:43:11 AM »
I would imagine it would be a lot cheaper in mild steel , aluminium is a bear to laser cut and weld. I have lasers at my factory - unfortunately not high enough power and of the wavelength to cut steel or ally - we do plastics like acrylics, perspex , corian , formicas  and other organic stuff like wood.
I would be interested in how the headamp sounds - I use Hd800's and have a set of AKG 702's on its way.
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Offline Mars

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Re: Van Waarde inspired OTL headphone amp
« Reply #16 on: December 20, 2010, 12:07:28 PM »
After the shock of the initial quote wore off, I discussed the manufacturing process with the sales representative at Fabrinox.

It turns out the material costs are negligible. It is the stripping and finishing (sanding the welds) that adds to the price. Since their welds are pretty neat, we have decided to do a trial run on weld only; no finishing.

The quote came to


MAR019-00000048-1 COVER PLATE 1200H4 02.0mm No
MAR019/00000048-2 HEAD AMP ENCLOSURE 1200H4 02.0mm No
Unit Price Total Price
(Excl. VAT) (Excl. VAT)
1 R 36.81 36.81
1 R 478.40 478.40
Comments:
WELDING INSIDE AND OUTSIDE
NO STRIP FINISH WELDING
COVER PLATE AND BOX SEPERATE
Subtotal
VAT
Total Net Price
Please Note:
R 515.21
R 72.13
R 587.34

This looks a bit better, and I've decided to go with this option, and will evaluate the outcome.
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Offline GearSlave

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Re: Van Waarde inspired OTL headphone amp
« Reply #17 on: December 20, 2010, 02:01:00 PM »
Just as a suggestion, try and have the chassis made without welds if possible. Just stick to bends for strength if you must. This is the way I've been doing it and the way it's done commercially; the less human work to do the cheaper it'll be. That way you can stick to aluminium without worrying about welding it.
Resistance is not futile; it is voltage divided by current (R=V/I)

Offline Mars

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Re: Van Waarde inspired OTL headphone amp
« Reply #18 on: January 07, 2011, 09:12:32 AM »
I think I might go with your idea in the future.

BTW the aluminium box is ready at Fabrinox. I'll pick it up next week and post the outcome.
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Offline Mars

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Re: Van Waarde inspired OTL headphone amp
« Reply #19 on: January 17, 2011, 09:54:28 PM »
Some pics of the chassis






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Offline kamikazi

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Re: Van Waarde inspired OTL headphone amp
« Reply #20 on: February 01, 2011, 08:32:33 PM »
Hows thing going with the build with your headphone amp?

I'm currently looking into getting a tube-based headphone amplifier for my new cans.

Offline Mars

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Re: Van Waarde inspired OTL headphone amp
« Reply #21 on: February 03, 2011, 10:51:13 AM »
I just got the chassis back from the painter:






I am going to mount all the hardware and post a pic.
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Offline kamikazi

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Re: Van Waarde inspired OTL headphone amp
« Reply #22 on: February 03, 2011, 07:03:38 PM »
Thanks for the response! The chassis looks really good, can't wait to see how it will look with everything mounted.

Offline Rendlan

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Re: Van Waarde inspired OTL headphone amp
« Reply #23 on: February 11, 2011, 12:39:30 PM »
Hi!

Any chance of a schematic for the final design?

Cheers!

R
He who wins the rat race... is still a rat.

Offline Rendlan

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Re: Van Waarde inspired OTL headphone amp
« Reply #24 on: February 12, 2011, 05:07:27 PM »
Also, would this be SRPP OTL?
He who wins the rat race... is still a rat.

Offline Mars

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Re: Van Waarde inspired OTL headphone amp
« Reply #25 on: February 16, 2011, 10:13:07 AM »
I am following the Wheatfield HA2 design. See the schematic in the User Manual here

http://www.pmillett.com/Wheatfield/manual.pdf
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Offline Mars

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Re: Van Waarde inspired OTL headphone amp
« Reply #26 on: July 13, 2011, 07:04:19 AM »
Hi All

Some update on the project.

  • the transformers are completed
  • and mounted
  • tube sockets are mounted
  • electrolytics are mounted
  • busy finalising the layout of the oil caps

I'll post a redrawn schematic soon.







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Offline iondb

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Re: Van Waarde inspired OTL headphone amp
« Reply #27 on: July 13, 2011, 07:57:29 AM »
This is looking really good.

Offline Mars

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Offline capetownwatches

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Re: Van Waarde inspired OTL headphone amp
« Reply #29 on: January 06, 2018, 10:43:55 PM »
Resurrecting this thread after 6 years or so... :)

There are no pics of the final product? I assume it was completed. What was the final cost?

Any chance of building another one similar...?
« Last Edit: January 06, 2018, 10:46:53 PM by capetownwatches »

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