Schiit Happened: The Story of the World's Most Improbable Start-Up
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captkirk

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I need another clue... Haven't been able to find the referenced Vidar prototype photos. (Of course, this new forum format doesn't help.)

Without another clue, my guess would be a Schiit OTL, one that would challenge some of the top contenders. Maybe 6SN7 drivers, some serious power tubes, and even the possibility of a rectifier tube?
And being Schiit, it would be able to handle low impedance headphones. Also, it would fit into the "Obsolete" theme, now that the pot has been stirred. It seems the Schiit TT is gathering momentum...

Fingers crossed! I'd love to see a Schiit end-game OTL amp, compatible for low and high impedance cans.
 
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slefty

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I need another clue... Haven't been able to find the referenced Vidar prototype photos. (Of course, this new forum format doesn't help.)

Without another clue, my guess would be a Schiit OTL, one that would challenge some of the top contenders. Maybe 6SN7 drivers, some serious power tubes, and even the possibility of a rectifier tube?
And being Schiit, it would be able to handle low impedance headphones. Also, it would fit into the "Obsolete" theme, now that the pot has been stirred. It seems the Schiit TT is gathering momentum...

The Valhalla is an OTL amp. OTLs generally do better into higher impedance loads, though I suppose that could be a bit of a generalization.
 
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rnros

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The Valhalla is an OTL amp. OTLs generally do better into higher impedance loads, though I suppose that could be a bit of a generalization.
Yes, I have one.
 
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FLTWS

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I had asked several months back about a headphone amp using the Freya tube types and I'm pretty sure I was told that while those tube types were fine for use in preamp to power amp scenarios with speakers they were not quiet enough for use with headphones.
 
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AndreYew

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I'm trying to learn how amps work. So, can some one please tell me where all the listed parts are in the pictures?
Here's my attempt at analyzing the photo ...

I'll take a shot at this with zero inside knowledge of Schiit's designs. I've annotated the photo with the letters to indicate what's what.
vidar-board-1920.jpg

a. 1 center-tapped transformer winding (for the HV regulated supply)
b. 4 transformer windings (for the high current supply)
c. 1 transformer winding (for the housekeeping stuff)
d. 1 bridge for the HV supply
e. 2 discrete-regulated HV supplies
f. 8 capacitors in the HV supplies
g. 4 bridges for the high-current supplies
h. 4 capacitors for the high-current supplies
na 2 power diodes (for housekeeping rectification)
i. housekeeping circuit with separate ground plane (not in Jason's list)
k. 2 capacitors for the housekeeping supplies
m. 3 separate regulated supplies for housekeeping functions

(there are no items marked with j and l)

I couldn't find the 2 power diodes for the housekeeping power supplies. Maybe they're underneath the board in that area.

HV = high voltage. You can see the marking on the PCB next to the header labeled "a" that it's +/- 70 V. The HV power supply is in the center of the board, and it's flanked by the two high current supplies on either side. The input signal traces are probably routed on the bottom side of the board that we can't see to the amp input circuitry which is in the middle of either side edges of the board next to the heatsinks.

The custom transformer has several windings that convert 120VAC into lower AC voltages, and these are delivered to the white jacks labeled a, b, and c. Once there, the voltages are rectified and converted to DC by bridge rectifiers (labeled BR on the board), and then regulated more tightly by voltage regulators (e and m). The high current stuff is not regulated. All the regulators look like linear regulators.

And some other interesting items:
n. Three output transistors per phase or complement (NPN, PNP). Mirrored on the other side of the board for the other channel.
o. Probably the drivers for the output transistors, maybe part of the bias circuitry for the output devices, and some part of the Schiit's proprietary amp topology, but these are transistors (usually marked Q on boards)
p. PEMs, which are basically nuts you press into circuit boards or panels so you can attach screws to them. I think this is an interesting feature here, because it seems the board is held onto the case from below. It might make manufacturing or servicing easier. Usually boards are on standoffs and a screw goes down from the top to sandwich the board between the screw head and the stand off.
q. Output relays and what appears to be an output inductor. There appears to be an input relay near the XLR jack, and all these relays are probably controlled by the housekeeping microcontroller.
r. This may be part of the monitoring circuit that measures current, voltage, and other things to feed back to the housekeeping microcontroller
s. An RJ-11 jack (like old-school wired telephone jacks) which is probably a serial port used to program and debug the microcontroller.
t. The housekeeping microcontroller.

It's also interesting to see that Jason and Mike have pretty different drawing styles for their layouts. Two things stand out:

1. Jason uses 45-degree angles on his lines with sharp corners while Mike likes smoothly curving lines. Modern CAD software do either one.
2. Mike thieves his ground planes (the little black dots that are empty voids in the copper plane, cf. the Gen. 5 USB board), which is usually done to make PCB manufacturing more reliable.

These are just educated guesses so please take them with a grain of salt!
 
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AviP

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I need another clue... Haven't been able to find the referenced Vidar prototype photos. (Of course, this new forum format doesn't help.)

Without another clue, my guess would be a Schiit OTL, one that would challenge some of the top contenders. Maybe 6SN7 drivers, some serious power tubes, and even the possibility of a rectifier tube?
And being Schiit, it would be able to handle low impedance headphones. Also, it would fit into the "Obsolete" theme, now that the pot has been stirred. It seems the Schiit TT is gathering momentum...

I believe he's referring to my post.

I'm still waiting patiently for a PivotPoint Magni 3...
 
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post-13611981
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FrivolsListener

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I need another clue... Haven't been able to find the referenced Vidar prototype photos. (Of course, this new forum format doesn't help.)

Without another clue, my guess would be a Schiit OTL, one that would challenge some of the top contenders. Maybe 6SN7 drivers, some serious power tubes, and even the possibility of a rectifier tube?
And being Schiit, it would be able to handle low impedance headphones. Also, it would fit into the "Obsolete" theme, now that the pot has been stirred. It seems the Schiit TT is gathering momentum...

Page 1477.
 
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post-13611989
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I need another clue... Haven't been able to find the referenced Vidar prototype photos. (Of course, this new forum format doesn't help.)

Without another clue, my guess would be a Schiit OTL, one that would challenge some of the top contenders. Maybe 6SN7 drivers, some serious power tubes, and even the possibility of a rectifier tube?
And being Schiit, it would be able to handle low impedance headphones. Also, it would fit into the "Obsolete" theme, now that the pot has been stirred. It seems the Schiit TT is gathering momentum...

Also, OTL? As in output transformerless? Where in Schiit's lineup do you see a single output transformer in the audio chain?

Confused.
 
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bosiemoncrieff

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@FLTWS

I recall the same thing, that Schiit tube choices for the L/M and Val were chosen for their low-noise for headphones. I'm still hoping for a scaled-up version of the Valhalla. One can dream...
What can Jason do? He added the gain in v2. It's already a preamp. He's ruled out rag with tubes vehemently, I might almost say explosively. He sees otl balanced as stupid. Saga freia tubes are too loud. Good luck stuffing into magni chassis.

What do you have left? Remote control? Better power supplies? Is pivot point a thing that otl is technically capable of adopting? (It doesn't seem likely.)
 
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rnros

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I had asked several months back about a headphone amp using the Freya tube types and I'm pretty sure I was told that while those tube types were fine for use in preamp to power amp scenarios with speakers they were not quiet enough for use with headphones.
I may have seen that, but if I did, that's certainly not my experience.
Some of the 6SN7s are my favorite tubes for use in the Lyr1. IMHO, a significant step above the 6DJ8 design in SQ.
Also, my experience with 6DJ8 variants is that they are more prone to hum, ringing, and microphonics.

The 6SN7s do have 600mA heaters so cannot be used in the Lyr2 or the MJ2.
However, currently listening to a 6C8G in the Lyr2 which is 300mA. A top terminal (coke bottle) version that predated the later GT (glass tube) 6SN7 versions.
It has all the great qualities of the better 6SN7s. Outstanding.

I do still use the small format 9 pin tubes, and still keep a substantial library of the 6DJ8 family, but my favorite is the REFL 6N3P-E, it's an older post and box frame design.
As good as the REFL 6N3P-E is, some of the 6SN7s match the tonal balance, accuracy, dynamics, and high/low extension, and then add a larger soundstage.
First impression was that it went in the direction of using balanced outputs.

Anyway, if I could have found a way to overcome the high output impedance of the Freya for headphone use, I would have tried it. :)
 
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Are you saying SET?
SET? Whazzat?

No, I'm assuming when people say OTL, they mean, output transformerless. Unless it's taken on some special meaning in the summit-fi world, that meant that there was no coupling transformer between the final amplifier and the output device (headphones or speakers) to match impedance. I don't see one on any of their designs, but then, output transformers used to be big and bulky.

Or, to use Jason's phrase, Schiit is already buzzword-compliant.
 
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Astral Abyss

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I want my own Macho Gorilla!

Please Jason, can I have a Schiit Art download page? It is free advertising for you.
I'd be satisfied with some Schitty wallpapers for my computer's.
 
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dmckean44

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I had asked several months back about a headphone amp using the Freya tube types and I'm pretty sure I was told that while those tube types were fine for use in preamp to power amp scenarios with speakers they were not quiet enough for use with headphones.
I doubt that, my phono stage uses 6SL7s (sister tube to the 6SN7) and is plenty quiet. You could definately use them in a headphone amp.
 
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