Schiit Happened: The Story of the World's Most Improbable Start-Up
Sep 26, 2017 at 12:32 PM Post #24,931 of 82,267
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I am curious the hear an answer to this.

If an amp is designed to be isothermal (meaning, all bias-affecting parts--VAS, drivers, Vbe multiplier, and outputs are closely coupled) then you can set it once when cold and forget it. Oh, and if the Vbe multiplier is a truly constant-voltage design, too (which takes a few more parts than the basic version.)

Basically, don't try to extend experience with one amp design to another amp design. Also, don't try to extend experience with one amp type to another amp type. Vidar, Magni 3, and Loki Mini all share a very similar gain stage. Vidar has to be biased with a constant-voltage Vbe multiplier and potentiometers, whereas Magni 3 and Loki Mini can get away with a couple of diodes and no pots. Why? Because one design has a much larger output stage, with very low-value emitter resistors. The others have smaller output stages, more closely thermally coupled to the diodes, and larger emitter resistors.

Horses for courses. Want to learn more? Start with Bob Cordell's amplifier design book.
 
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Sep 26, 2017 at 12:36 PM Post #24,932 of 82,267

notfitforpublic

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This may be a stupid question. Currently splitting the signal out of a Bifrost Multibit to 2 different amps via a couple of ViaBlue RCA splitters. Would I be able to slide a Loki mini between the Bifrost and amps, splitting the signal out of the Loki mini with out causing any issues? or is a Sys a necessary part of the chain to avoid any degradation/issues/whatever?
 
Sep 26, 2017 at 12:39 PM Post #24,933 of 82,267
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This may be a stupid question. Currently splitting the signal out of a Bifrost Multibit to 2 different amps via a couple of ViaBlue RCA splitters. Would I be able to slide a Loki mini between the Bifrost and amps, splitting the signal out of the Loki mini with out causing any issues? or is a Sys a necessary part of the chain to avoid any degradation/issues/whatever?

No problem at all, as long as the Loki is on. As noted in the FAQ, when it's powered off, it acts like a bypass, but the unpowered inputs load the signal and cause distortion that may be audible (for the more technically minded, the distortion is about 60dB down at 1V, but it's a picket fence--it goes way out to very high harmonics.) The solution--make sure Loki is turned on.
 
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Sep 26, 2017 at 12:44 PM Post #24,934 of 82,267

notfitforpublic

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No problem at all, as long as the Loki is on. As noted in the FAQ, when it's powered off, it acts like a bypass, but the unpowered inputs load the signal and cause distortion that may be audible (for the more technically minded, the distortion is about 60dB down at 1V, but it's a picket fence--it goes way out to very high harmonics.) The solution--make sure Loki is turned on.

Nice! I'm assuming the use of the by pass switch is unhindered? The same distortion will not occur with the by pass switch toggled to off?
 
Sep 26, 2017 at 12:47 PM Post #24,935 of 82,267

AudioBear

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I was shocked by the announcement of Loki this morning. Now that I've had a cup of coffee I have an observation and a question. Jason mentioned all the equalizers that we could once buy which have been taken away from us in the drive for audio perfection. Was it audio perfection or was it some kind of mind control? Maybe even an almost fascist desire to get us all to conform with what was seen as RIGHT. Jason hasn't just given us back the equalizer, he has freed us. This is no small moment in time. Is there a Norse good known as the liberator?

Let me backup about 40 or 50 years. Does anybody remember the Sansui 500A reverb? It sat right next to the Sansui 5000A or X receiver. You know, the small box with the two curved rainbows (one up one down) in the display. With it one could produce amazing sounds that were totally unreal and not musical. Set on low, however, the little box added a very pleasant dimension to the music. It's hard to explain unless you've heard a little reverb and a lot of distortion. Turned way up it produced an almost psychedelic experience. Totally not real but if you had drunk enough beer or added other substances, it was a trip. The point here is that in 1970 we were FREE to do whatever the hell we wanted to do with the music and we did it and we loved it. Jason has re-opened the doors to our freedom. Who knows maybe VW micro vans painted in multicolored designs will make a come back.

I have a confession. I am a closet equalizer. I have always known my preferences were more important than audio purity. Of late I have been using digital equalizers. I'd like to know what's wrong with them. The variable Q and selection of filter types is very appealing. This is a serious question for @Jason Stoddard. Where and how do they fall down? In principle shouldn't in silico equalization be feasible?

I'd also like to know how and -- more importantly-- why the center frequencies were chosen. I know it wasn't arbitrary. What was the logic? I think there's something to learn when designers with years of audio experience focus on 4 specific frequencies. In fact, in light of all the 10, 12, and 31 band equalizers that have been made, how was Schiit able to focus on 4 frequencies that they believed would make the most difference?
 
Sep 26, 2017 at 12:47 PM Post #24,936 of 82,267
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Nice! I'm assuming the use of the by pass switch is unhindered? The same distortion will not occur with the by pass switch toggled to off?

As long as Loki is on, yes.

It's the same for any device--if the inputs are unpowered, it can be a nonlinear load. If you're splitting a signal to two amps, they should both always be on to avoid loading the signal.
 
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Sep 26, 2017 at 12:48 PM Post #24,937 of 82,267

Thouston

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If an amp is designed to be isothermal (meaning, all bias-affecting parts--VAS, drivers, Vbe multiplier, and outputs are closely coupled) then you can set it once when cold and forget it. Oh, and if the Vbe multiplier is a truly constant-voltage design, too (which takes a few more parts than the basic version.)

Basically, don't try to extend experience with one amp design to another amp design. Also, don't try to extend experience with one amp type to another amp type. Vidar, Magni 3, and Loki Mini all share a very similar gain stage. Vidar has to be biased with a constant-voltage Vbe multiplier and potentiometers, whereas Magni 3 and Loki Mini can get away with a couple of diodes and no pots. Why? Because one design has a much larger output stage, with very low-value emitter resistors. The others have smaller output stages, more closely thermally coupled to the diodes, and larger emitter resistors.

Horses for courses. Want to learn more? Start with Bob Cordell's amplifier design book.
Thank you, Jason
 
Sep 26, 2017 at 12:50 PM Post #24,938 of 82,267

Astral Abyss

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Looks like I could run a Vali 1 (or Magni 3), Modi 2U, Eitr, and Loki Mini all off Cthulhu. If so, that's a pretty neat setup. My OCD approves.

Edit: Or will Vali 1 blow it up? Can't tell from the specs.
 
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Sep 26, 2017 at 12:53 PM Post #24,939 of 82,267

Left Channel

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Ordered, with 6" PYST RCA cables for convenience. Thanks Jason! I'm now on my third pair of desktop speakers and second set of headphones this year, chasing the perfect sound. We don't all have room for giant monitors and twenty sets of cans. What's good for music isn't always good for news and talk. What's good for hi-res acoustic jazz isn't best for low-res Sixties soul. This is the solution! Man, I was getting so desperate a few months back, I was seriously looking at dusty old 1970s equalizers (don't know where I would have fit one of those...probably under the desk), and considering adapting an equalizer meant for cars.
 
Sep 26, 2017 at 1:08 PM Post #24,941 of 82,267

FLTWS

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Only 2 years on the warranty?
Will there be an eventual balanced version of Loki?
 
Sep 26, 2017 at 1:17 PM Post #24,943 of 82,267
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Schiit Audio Stay updated on Schiit Audio at their sponsor profile on Head-Fi.
 
https://www.facebook.com/Schiit/ http://www.schiit.com/
Sep 26, 2017 at 1:22 PM Post #24,944 of 82,267
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I was shocked by the announcement of Loki this morning. Now that I've had a cup of coffee I have an observation and a question. Jason mentioned all the equalizers that we could once buy which have been taken away from us in the drive for audio perfection. Was it audio perfection or was it some kind of mind control? Maybe even an almost fascist desire to get us all to conform with what was seen as RIGHT. Jason hasn't just given us back the equalizer, he has freed us. This is no small moment in time. Is there a Norse good known as the liberator?

Let me backup about 40 or 50 years. Does anybody remember the Sansui 500A reverb? It sat right next to the Sansui 5000A or X receiver. You know, the small box with the two curved rainbows (one up one down) in the display. With it one could produce amazing sounds that were totally unreal and not musical. Set on low, however, the little box added a very pleasant dimension to the music. It's hard to explain unless you've heard a little reverb and a lot of distortion. Turned way up it produced an almost psychedelic experience. Totally not real but if you had drunk enough beer or added other substances, it was a trip. The point here is that in 1970 we were FREE to do whatever the hell we wanted to do with the music and we did it and we loved it. Jason has re-opened the doors to our freedom. Who knows maybe VW micro vans painted in multicolored designs will make a come back.

I have a confession. I am a closet equalizer. I have always known my preferences were more important than audio purity. Of late I have been using digital equalizers. I'd like to know what's wrong with them. The variable Q and selection of filter types is very appealing. This is a serious question for @Jason Stoddard. Where and how do they fall down? In principle shouldn't in silico equalization be feasible?

I'd also like to know how and -- more importantly-- why the center frequencies were chosen. I know it wasn't arbitrary. What was the logic? I think there's something to learn when designers with years of audio experience focus on 4 specific frequencies. In fact, in light of all the 10, 12, and 31 band equalizers that have been made, how was Schiit able to focus on 4 frequencies that they believed would make the most difference?

This really deserves its own chapter, but two quick answers:

1. Why the bands were chosen: music. Foundational bass, floor bounce/midbass honk, presence/rasp, and sheen/treble. Another couple of bands would be nice, but that's a bit big for this chassis. Covered in the chapter.
2. Digital EQ: sure, that's another approach. We don't like the current filters used (not surprising, right)? Some calculate at too low precision. Also only digital. What if you want to EQ your turntable?
 
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