More Disruptive Schiit (Vidar)

[esldude]

44 minutes ago, Speed Racer said:

This "no it all" type of response is what turns me off to this site. Do you really think you know more about what is and isn't a bridged amp than Jason does?

 

How many amps have you designed and successfully sold? What are your credentials that allow you to admonish Jason like this?

I do in fact know enough to understand what the Vidar is going in regards to stereo vs mono.  That is all I need to know in this case.  What it really and truly in the physical world is doing is as I describe it and credentials or no, Jason Stoddard's pronouncements or no, that is what it will do.  In fact I doubt Jason would have a big point of disagreement with me.  The only real point would be terminology of balanced differential rather than bridged.  The functioning for evaluating power and speaker loads is the same.

 

You don't understand it or you wouldn't be arguing with me.  That is okay, I can overlook it.  But don't start off on some big rant about Jason Stoddard vs me.  This is not what people wish to read here.  I've posted info that is useful to understanding what the Vidar will do in regard to different speakers loads and mono vs stereo.  The info is solid and agrees with literature from Schiit.  I'll leave it at that.  If you are not convinced....too bad.  The part about whether the Vidar is bridged or balanced differential is trivial and has no bearing on the issue of its power. 

[Don Hills]

A bridge circuit takes an input signal (single ended or differential) and produces two equal and opposite output signals. A "bridged" amplifier has this bridge circuit at its input. In the case of the Vidar, the differential output stage of the preamp is used as the bridge circuit instead, hence Schiit's insistence that the preamp output be truly differential. If it's not, and the two wires of the preamp output aren't equal (and opposite) in level, the two channels of the Vidar will not be driven equally.

 

So when Jason says the Vidar is not bridged in mono mode, he's strictly correct, there's no bridging circuit to switch in. Each channel remains separate. In theory, you could take the cable from the differential output of the preamp, cut off the XLR plug at the amp end, and wire the two signal lines to the two RCA inputs and get the same result as using the XLR input.  Of course, in practice the RCA and XLR inputs may differ in detail.

[opus101]

1 hour ago, Speed Racer said:

This "no it all" type of response is what turns me off to this site. Do you really think you know more about what is and isn't a bridged amp than Jason does?

 

How many amps have you designed and successfully sold? What are your credentials that allow you to admonish Jason like this?

 

Jason's obviously wrong about the 'recycling' of the output of one amp channel into the input of the other as being THE definition of what a bridged amp is. As esl has already carefully explained - there's more than one way of skinning the cat. Jason's also quite mistaken in introducing an irrelevance - to wit, whether an amp is 'Lin' topology or not.

 

From what he's said about the amp its presumably a singleton input transistor rather than the nowadays more common LTP input. Nothing particularly new or disruptive about using a single transistor input - JLH's classic 1969 Wireless World design used the same. As have a number of IC amps (TDA2003 is one example).

[esldude]

1 hour ago, Don Hills said:

A bridge circuit takes an input signal (single ended or differential) and produces two equal and opposite output signals. A "bridged" amplifier has this bridge circuit at its input. In the case of the Vidar, the differential output stage of the preamp is used as the bridge circuit instead, hence Schiit's insistence that the preamp output be truly differential. If it's not, and the two wires of the preamp output aren't equal (and opposite) in level, the two channels of the Vidar will not be driven equally.

 

So when Jason says the Vidar is not bridged in mono mode, he's strictly correct, there's no bridging circuit to switch in. Each channel remains separate. In theory, you could take the cable from the differential output of the preamp, cut off the XLR plug at the amp end, and wire the two signal lines to the two RCA inputs and get the same result as using the XLR input.  Of course, in practice the RCA and XLR inputs may differ in detail.

Which is why it brought to mind the balanced differential Sumo Andromeda which used to work just that way.  You needed xlr to RCA adapters from a balanced preamp to get best results.

 

 

 

[Speed Racer]

For an amp to be a "bridged" amp, some actual bridging needs to take place. None is with Vidar. There may be multiple ways to setup a monoblock amp, but not all of them are "bridged". 

 

You think to much or yourselves and must really like hearing yourself talk. Obviously wrong? Wow.....

[fas42]

Ummm ... https://en.wikipedia.org/wiki/Bridged_and_paralleled_amplifiers#Bridged_amplifier

 

[soares]

Any dealers in NY?

Thank you,

 

Jorge

[The Computer Audiophile]

1 minute ago, soares said:

Any dealers in NY?

Thank you,

 

Jorge

 

 

http://www.schiit.com/faq/dealers

[soares]

17 minutes ago, The Computer Audiophile said:

 

 

http://www.schiit.com/faq/dealers

Than k you. I was aware of the link. The problem is that when you accede the dealers links, they show several brands and not Schiit. That's why I was wondering if someone in NY had already listening to the Vidars.  

Best,

Jorge

[unbalanced output]

On 19/07/2017 at 10:21 AM, firedog said:

High current amps can often sound better, even if lower wattage, than a higher wattage, lower current amp with less efficient speakers. 

 

Less efficient speakers often have lower impedance and therefore higher current demand for the same power. Vidar is designed with views to high power at higher impedances, therefore it has lower current capability than amps with same power that work at lower impedances (which also makes it cheaper to build). Let's not forget that speakers impedances are not constant, they vary with frequency and power. Essentially, a good share of the current will end up powering the bass (lower impedance, higher power region) and that's why amps usually struggle with the bass. 

 

Not quite sure of what kind of speakers benefit of high power at high impedances.

 

 

[Speed Racer]

12 minutes ago, unbalanced output said:

 

Less efficient speakers often have lower impedance and therefore higher current demand for the same power. Vidar is designed with views to high power at higher impedances, therefore it has lower current capability than amps with same power that work at lower impedances (which also makes it cheaper to build). Let's not forget that speakers impedances are not constant, they vary with frequency and power. Essentially, a good share of the current will end up powering the bass (lower impedance, higher power region) and that's why amps usually struggle with the bass. 

 

Not quite sure of what kind of speakers benefit of high power at high impedances.

 

 

What? Vidar is a 100 watts per channel at 8 ohms and 200 watts per channel at 4 ohms. It has no problem driving 4 ohm high efficiency speakers at any volume I can stand. Vidar has no problem with bass on my setup and my Tekton Design Double Impact speakers do go low!

 

Oh, I did run my Vidar in monoblock mode and at any volume I could stand it worked great. Again bass was not a problem. 

[esldude]

1 hour ago, unbalanced output said:

 

Not quite sure of what kind of speakers benefit of high power at high impedances.

 

 

Electrostats.  Most power as you noted is in the bass.  Certainly 500 hz and below covers most power requirements in music. Electrostats typically have a high impedance in the bass which drops at higher frequencies.  They need a high power amp mainly for the extra voltage output.  They are not requiring much current at lower frequencies. 

 

 

Here is a Quad ESL63.  It reaches about 32 ohms there around 100 hz.  A Vidar probably would do great running in mono on those.  Now here is a Soundlab A1

 

 

There is enough reactance there you can't have a totally wimpy amp on current, but it needs voltage more than current.

 

Sanders made an amp designed for ESL loads and reactances.  One version was 1000 wpc at 8 ohms.  That meant it could put out a signal of 90 volts.  Which meant it was able to push out power into the lower frequencies of ESL speakers.

 

Now in the case of Quad they limited input to 40 volts peak or 28 v rms to prevent arcing over the speaker.  If you did, it shorted the amp inputs to prevent speaker damage.  I seem to recall the Quad 57 shouldn't receive more than 33 volts peak to prevent damage.  I fixed some warning LEDs on the 57s I had to alert you when you neared 28 volts. 

[The Computer Audiophile]

The Vidars arrive Monday. I have three pairs of speakers coming in to test with them as well. 

 

Some from Dynaudio, Focal, and Sonus Faber. Based on the comment above I want to get a pair of electrostats now.

 

Not sure I can accommodate it, but if I can, any recommendations?

[esldude]

Well Martin Logans CLX or the Soundlabs come to mind.  You want a full range model, not hybrids with cone woofers. 

 

What is the current Quad is it the 2912?

 

Audiostatic is one I would like to see reviewed.  Audiostatics are not so highly expensive as the other full range ESL panels have become.   They ship worldwide direct to the customer which seems like a good plan in the internet age.  So if they would agree to let you review some that would be my choice. We need affordable full range ESLs. 

http://www.audiostatic.com/models.html

 

There is also the King sound ESLs.  They are less expensive than some though I don't know much about them.

http://www.kingsaudio.com.hk/speaker.html

 

Any other full range ESL panels out there?

 

 

 

 

[unbalanced output]

5 hours ago, esldude said:

Electrostats.  Most power as you noted is in the bass.  Certainly 500 hz and below covers most power requirements in music. Electrostats typically have a high impedance in the bass which drops at higher frequencies.  They need a high power amp mainly for the extra voltage output.  They are not requiring much current at lower frequencies. 

 

 

Here is a Quad ESL63.  It reaches about 32 ohms there around 100 hz.  A Vidar probably would do great running in mono on those.  Now here is a Soundlab A1

 

 

There is enough reactance there you can't have a totally wimpy amp on current, but it needs voltage more than current.

 

Sanders made an amp designed for ESL loads and reactances.  One version was 1000 wpc at 8 ohms.  That meant it could put out a signal of 90 volts.  Which meant it was able to push out power into the lower frequencies of ESL speakers.

 

Now in the case of Quad they limited input to 40 volts peak or 28 v rms to prevent arcing over the speaker.  If you did, it shorted the amp inputs to prevent speaker damage.  I seem to recall the Quad 57 shouldn't receive more than 33 volts peak to prevent damage.  I fixed some warning LEDs on the 57s I had to alert you when you neared 28 volts. 

 

Great explanation as always! Those are not typical curves, many speakers have low impedances at lower bass and midrange (see Focal example which has 3 is at 100 Hz). Also in real life the actual loads can drop below the charts since impedance will vary as the frequencies are composed. 

 

 

7 hours ago, Speed Racer said:

 

What? Vidar is a 100 watts per channel at 8 ohms and 200 watts per channel at 4 ohms. It has no problem driving 4 ohm high efficiency speakers at any volume I can stand. Vidar has no problem with bass on my setup and my Tekton Design Double Impact speakers do go low!

 

Oh, I did run my Vidar in monoblock mode and at any volume I could stand it worked great. Again bass was not a problem. 

 

Tekton site tells me these are 98dB speakers you have - that's horn-like sensitivity. They should as well work with a 1 wpc amplifier, so...? 

[Speed Racer]

What was I thinking....the Vidar amp must be total and utter crap. You know so much more than anyone else....

[unbalanced output]

2 hours ago, Speed Racer said:

What was I thinking....the Vidar amp must be total and utter crap. You know so much more than anyone else....

 

Dude if you plug it in and it works for you and you're happy, I'm fine with it. But you're not going far with this line of argumentation.

[ShawnC]

10 hours ago, The Computer Audiophile said:

The Vidars arrive Monday. I have three pairs of speakers coming in to test with them as well. 

 

Some from Dynaudio, Focal, and Sonus Faber. Based on the comment above I want to get a pair of electrostats now.

 

Not sure I can accommodate it, but if I can, any recommendations?

Magnepan 1.7, see if Audio Perfection will borrow you a pair.

[Johnseye]

12 hours ago, The Computer Audiophile said:

The Vidars arrive Monday. I have three pairs of speakers coming in to test with them as well. 

 

Some from Dynaudio, Focal, and Sonus Faber. Based on the comment above I want to get a pair of electrostats now.

 

Not sure I can accommodate it, but if I can, any recommendations?

 

2 hours ago, ShawnC said:

Magnepan 1.7, see if Audio Perfection will borrow you a pair.

 

Without a doubt Magnepan. 3.7i.

[crenca]

7 hours ago, unbalanced output said:

 

Tekton site tells me these are 98dB speakers you have - that's horn-like sensitivity. They should as well work with a 1 wpc amplifier, so...? 

 

 

I have never seen a sensitivity measurement of a Tekton speaker that did not come in a minimum of 3db below their own advertised specs.  This one done by Stereophile comes in a full 6 db less:

 

https://www.stereophile.com/content/tekton-design-enzo-xl-loudspeaker-measurements

 

That said I appreciate what they are trying to do in the market - just wish they would stifle the exaggerated sales pitch a bit...

[unbalanced output]

1 hour ago, crenca said:

 

I have never seen a sensitivity measurement of a Tekton speaker that did not come in a minimum of 3db below their own advertised specs.  This one done by Stereophile comes in a full 6 db less:

 

https://www.stereophile.com/content/tekton-design-enzo-xl-loudspeaker-measurements

 

That said I appreciate what they are trying to do in the market - just wish they would stifle the exaggerated sales pitch a bit...

 

I can believe in it, sounded exaggerated to me (pun intended)

[ShawnC]

5 hours ago, ShawnC said:

Magnepan 1.7, see if Audio Perfection will borrow you a pair.

Better yet, go to tour the Magnepan facility and ask if you can borrow a pair for a year or so for doing comparison reviews.  Lots of electrostatic owners here, they would love to hear how some of your reviews involve both cone and electrostatic speakers.  Or create 2 systems in your space.  You could invite a sales rep over so they can hear there product with other gear.  Then invite me over for a Pearl Jam jam session.

 

Just spit balling here and having fun.  

[clipper]

4 hours ago, Johnseye said:

 

 

Without a doubt Magnepan. 3.7i.

+1 on this.

 

GREAT speakers.  Plus, it's a Minnesota product (right outside of Minneapolis).

 

 

[Ralf11]

I also vote for the Magnepan 3.7i - do you know Wendell at all?

[The Computer Audiophile]

1 hour ago, Ralf11 said:

I also vote for the Magnepan 3.7i - do you know Wendell at all?

I've had the personal tour of Magnepan from Wendell. I'll look into getting a pair.