Looking for a new project. Anything similar to the Schiit Lyr?

[regal]

Yes but the concept is long overdue, especiall with the ortho headphones int the mix now. Believe me I have looked hard at an SET design and short of a GM70 a clean 2W into 38 ohms isn't happening.

[simon7000]

Originally Posted by KatieandDad

What an unfortunate choice of name.

In English that is Sierra (S) Hotel (H) India (I) Tango (T) Liar.

When I saw the pot listing I thought it was a bad joke!

The National LM4562 has changed part number. It seems it is pronounced to sound like an offensive term in China!

[rob g]

In a way it is a great name for a piece of Hi-Fi, designed to sound brutally revealing.
It claims to be very bad at being inaccurate, cos it's a sh1t liar!

[regal]

I did a little probing on my new Lyr, the tube stage is a simple common cathode, resistive loaded plates with the shared cathode ccs, operating point with my less than fresh amperex orange globes is 110V anode, 2.7V cathode, which gives me about 3mA per tube . Its a good design, not some enemic chinese SRPP run 100V B+. Its quiet with Grados so the B+ regulation must be good stuff. The p-p mosfet output is well laid out. The coupling cap in front of the output stage is a decent Wima 4.7 MKP4. If I hear a room for improvement the bass seems a bit too snappy/harsh at high high power levels (fine at normal levels).

I guess a DIY version could be done for about the same price without a whole lot gained. Would do a little better with a more linear operating point, more like 125V/5mA.

I would be more interested in an no expense tube hybrid headamp. Maybe tube rectified/Salas HV B+ to 4p1l (coleman reg), to lateral mosfet p-p type buffer. Would be expensive and time consuming but could be worth it. I am surprised there isn't much interest in building a DIY ortho amp, everyone seems content to plug them into antique Sansui receivers

[rjm]

Tube+MOSFET hybrid headphone amps are bit ... uninteresting. They are basically two fully independent sections, one high voltage, low current, the other low voltage, high current. Since the don't ideally share a common power supply, the circuit design quickly devolves into a tube preamplifier and a MOSFET headphone buffer that just happen to share a common chassis.

As for the Lyr, I'm sure it's a solid-by-DIY-standards design, given it's heritage. I'm most interested to know how the dynamic biasing is done:

It works by sensing the current flowing through the output stage, and dynamically reconfiguring from Class-A single-ended to push-pull Class AB.

I've seen amps with this general design claim surface a few times over the years, but never seen a circuit schematic to tell me exactly what is being done.

[alfa147x]

I know they're using some type of ic for the switching. I'll order one soon. I'll post when I receive it. Then we can decipher it together.

[KatieandDad]

Originally Posted by rob g

In a way it is a great name for a piece of Hi-Fi, designed to sound brutally revealing.
It claims to be very bad at being inaccurate, cos it's a sh1t liar!

The Ford Capri had to be renamed because - apparently - Capri is an oriental name for a lady of the night.

[regal]

Originally Posted by rjm

Tube+MOSFET hybrid headphone amps are bit ... uninteresting. They are basically two fully independent sections, one high voltage, low current, the other low voltage, high current. Since the don't ideally share a common power supply, the circuit design quickly devolves into a tube preamplifier and a MOSFET headphone buffer that just happen to share a common chassis.

As for the Lyr, I'm sure it's a solid-by-DIY-standards design, given it's heritage. I'm most interested to know how the dynamic biasing is done:
I've seen amps with this general design claim surface a few times over the years, but never seen a circuit schematic to tell me exactly what is being done.

Not all hybrids are unitnteresting, with these new orthos we need to swing upwards of 17Vrms, that equivalent to a 35watt amplifier for speakers (without has much current delivery). If you had looked at the EHHA it is not a tube stage plus separate buffer. Its a differential input-VAS-currentbuffer all shared powersupply with global feedback, just has a tube differential input instead of jfet.

Even the lower model orthos need a solid 6Vrms swing into 38 ohms which is a challenge for SET tube folks.


I think the dynamic biasing just means the output stage is push-pull biased around 100mA, and when the volume/load high enough it goes into class B just like any heavily biased class A push-pull stage. But I didn't look at the mosfet stage, the Lyr does fit your tube preamp + mofset stereotype.

[john57]

The very best sounding hybrid tube amp that I have heard is the Cavalli Audio Liquid Glass Amplifier at $3500 which has about the same power as the Lyr. Does anyone knows how that is designed?

[Lord Soth]

Originally Posted by john57

The very best sounding hybrid tube amp that I have heard is the Cavalli Audio Liquid Glass Amplifier at $3500 which has about the same power as the Lyr. Does anyone knows how that is designed?

Yes.... For a bargain price of only $3,499, the schematics are all yours.