Those are some good looking amplifiers! Well finished too.
Absolutley, I love the creative use of wood to bring some esthetic warmth to an otherwise cold metal chassis.
Here is my second Super Simple Single Stage preamp (The 4S MKII), slightly better values this time which has brought the distortion down to 0.2%. Much better and neater layout and construction. All component-2-component wiring, silver solder and Alps blue velvet and solid brass knob.
Colour is Epoxy Beaten Copper. Two switchable inputs on the back. Golden Dragon 12AU7 installed. The sound is natural to flat. Over 8db of gain and frequency range is 10hz to 152kHz. Again is runs from a 24V AC wall wart. PS and amp on the one cct. brd. See this thread for schematic etc.
Colour is Epoxy Beaten Copper. Two switchable inputs on the back. Golden Dragon 12AU7 installed. The sound is natural to flat. Over 8db of gain and frequency range is 10hz to 152kHz. Again is runs from a 24V AC wall wart. PS and amp on the one cct. brd. See this thread for schematic etc.
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Here is the orginal cct. I used. In this build (MKII) the Rp was increased to 27K and the Rc dropped to 800 ohms. Originally the Rc was not bypassed.
I have one other to build where there is no Rfb and no Routput. Rc is un-bypassed and no Rfb.
An even earlier cct.to this one has Rfb set at 660K. Twice what is in this cct.
I have one other to build where there is no Rfb and no Routput. Rc is un-bypassed and no Rfb.
An even earlier cct.to this one has Rfb set at 660K. Twice what is in this cct.
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What is it?
The driver's schematic basis in attachment. It is rather Berglund's schematic. 6C33C used with cathode winding. Total transformer's Ra = 1.1kOhm, inductance 8H.
My van Waarde headphone amp
Hi,
A couple of years ago I built a van Waarde headphone amp based on the project at Headwize (HeadWize - Project: A Single-Ended OTL Amplifier for Dynamic Headphones by Aren van Waarde). Here are a few pictures.
BTW, thanks to all. I've been lurking here for a while and just joined up. Truly a wealth of info here. I've learned a lot.
Hi,
A couple of years ago I built a van Waarde headphone amp based on the project at Headwize (HeadWize - Project: A Single-Ended OTL Amplifier for Dynamic Headphones by Aren van Waarde). Here are a few pictures.
BTW, thanks to all. I've been lurking here for a while and just joined up. Truly a wealth of info here. I've learned a lot.
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Nice ! i build the HeadWize 6N1P amp. Works good.. but low gain with my low impedance Sony headphone. Wich headphone do you use ?
The heatsink at the bridge rectifier.. isnt that a bit overkill ?
Thank you! I know the case is not so pretty but it was just an experiment and I really didn't expect it to become my main listening (with headphones) amp.
I use Sennheiser HD600. They have an impedence of 300 ohms and work very well with the amp. I also increased the out caps to 220 microFarad.
That heatsink is actually barely enough since it has to deal with the heater voltage regulator and not just the bridge. I have vents in the back and on top and even then after a couple of hours the whole amp is quite warm. But it really does sound wonderful.
As I mentioned, I built the amp to see if there was really something about "the tube sound". I also considered the amp you built. In fact I don't even remember why I chose to built the van Waarde instead.
Are you happy with yours?
- Michael (aka Hummel)
EL84 set finished
Here is an EL84 SET that I have just finished for my father.
Basically a junkbox amp, a little of everything that I had laying around.
Note: haven't gone through final cleaning and dust specks showed up with the flash, and the transformer is a dark international blue. The flash made the transformer look out of place, but it is a really dark blue.
The sides are Black Walnut
Oh, the layout of the deck is like the one Decware makes, but the circuit is different.
I think this one has a very clean sound with open-baffle fullrange 12" Heppners, and no hum can be detected with your ear to the speaker cone.
Here is an EL84 SET that I have just finished for my father.
Basically a junkbox amp, a little of everything that I had laying around.
Note: haven't gone through final cleaning and dust specks showed up with the flash, and the transformer is a dark international blue. The flash made the transformer look out of place, but it is a really dark blue.
The sides are Black Walnut
Oh, the layout of the deck is like the one Decware makes, but the circuit is different.
I think this one has a very clean sound with open-baffle fullrange 12" Heppners, and no hum can be detected with your ear to the speaker cone.
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Here is an amplifier using 6GC5's
This amp I built for the den, it uses 6GC5's for the PP output and then I am using a pair of 12BH7 for voltage amp and phase inversion. I like the sound of this amp with the 12BH7's up front. I tried many other tubes up front, but this is what sounded best to my ears.
This amp I built for the den, it uses 6GC5's for the PP output and then I am using a pair of 12BH7 for voltage amp and phase inversion. I like the sound of this amp with the 12BH7's up front. I tried many other tubes up front, but this is what sounded best to my ears.
