Legato 3 - Look ma! No caps!

[sinski]

Use coax spdif from Touch directly to Buffalo II and apply tweaks from this site :
soundcheck's - audio@vise: soundcheck's Squeezebox Touch Toolbox 2.0

I am using SBT with BII

 

[Anima]

Silly question, but how literally should i take "directly"? - can i take a coax terminal and connect directly to the b2/Legato internally? Or do i need a circuit board to provide this functionality? Probably, i need this board, right? http://www.twistedpearaudio.com/digital/wm8804.aspx

I'm sorry, i bought the L2, B2 and tridents back in january.. i've forgotten a lot of stuff while waiting for my items.

 

[BrianDonegan]

You should take it literally. Direct into the Buffalo.

 

[BrianDonegan]

We are accepting pre-orders for the Legato-III again, and will begin shipping the week of June 12th.

 

[natzev_i]

Brian, when the Legato 3 Manual will be out, please?
Thanks!

 

[BrianDonegan]

I just posted a draft of the 3.0.1 manual here: http://www.twistedpearaudio.com/docs/linestages/legato_user_manual_3.1.0.pdf

It is accessible from the Legato web page as well. I will get the final version up tonight or tomorrow.

 

[natzev_i]

Thank you, Brian!

 

[avr300]

L3.1 is in and it's working perfectly.

Thanks Russ and Brian. Great job you have done.

 

[ronpod]

avr -- Another achievement well done! Do report back your listening feedback...

 

[Anima]

hello Brian and Russ

Can i buy a Legato V3 board and perhaps order the components that are not already in the legato V2 board?

As i wrote, i have not received my Legato yet and wonder why i should not go with a legato V3 instead. I mean, the board is only ~20 USD.. i presume many of the components are the same..

 

[MartinC700]

Aaarrrgghhhh....Legato 3.1 working fine but my Stax headphone amp does not like dc on the balanced input, so I am having to run SE. I guess caps on the balanced outputs are needed for me.

FYI took the placid voltage down to +/- 13v from 13/15 on the Legato 2 and total current draw is only slightly higher than the 2, so the old Placid BP will be in for a while until I get the case modded to fit the BP HC.

Verdict on the sound compared to the v2 tomorrow.

Regards

 

[reo]

Hi Folks
I also put together Legato3.1 without the headphone buffer . Also for now i have not installed the opamp based Bal/SE stage . Initially wanted to Hook my speakers to the SE but no signal going through ,..... therefore i hooked them up on the BAL section of the + and GND . , i don't think i will leave it as is , cause with the voltmeter , the voltage reads 8.6V on either left or the right channels .and decreasing by .1V every minute or so So any options ?

Question : can i hook up my speakers on the + and - of the Bal section for SE power amp ?

If all else fails then i will inevitably have to install the BAL/SE opamp if i want to have the SE working ? and also have a reading of 0volts on the SE outputs , like is what is showing on the + and - reading that is showing when measuring it .
Oh and by the way I/V is working fine at this point in time , but with the voltage reading on the + and - it worries me ..

 

[Russ White]

Hi Folks
I also put together Legato3.1 without the headphone buffer . Also for now i have not installed the opamp based Bal/SE stage . Initially wanted to Hook my speakers to the SE but no signal going through ,..... therefore i hooked them up on the BAL section of the + and GND . , i don't think i will leave it as is , cause with the voltmeter , the voltage reads 8.6V on either left or the right channels .and decreasing by .1V every minute or so So any options ?

Question : can i hook up my speakers on the + and - of the Bal section for SE power amp ?

If all else fails then i will inevitably have to install the BAL/SE opamp if i want to have the SE working ? and also have a reading of 0volts on the SE outputs , like is what is showing on the + and - reading that is showing when measuring it .
Oh and by the way I/V is working fine at this point in time , but with the voltage reading on the + and - it worries me ..

Why would you expect any signal at the SE output without the BAl/SE stage? Have you read the manual or looked at the schematic? Legato 3.1 is *Definitely* not intended to by used with only half the circuit. Either use the BAL/SE stage or install caps.

 

[AudioDAC]

Hi Russ.
When I buy legato III with buffers, can I have a signal from op amp (to amplifier) and from buffer (to headphones) simultaneously? Or may be it is possible to install any switch
to switch the circuit from opamp to amplifier and from buffer to headphones? Does the buffers (their loops to op amps) makes any load to op amp and have influence on them? (I mean on their sound).
thanks
and regards

 

[wktk_smile]

Question : can i hook up my speakers on the + and - of the Bal section for SE power amp ?
..

I recommend installing output caps as Russ said. It's easy to try.
I built Legato3 on previously bought L2 board. Excellent sounding even with output caps.

 

[reo]

thanks Folks
for your insight and perspectives . In the meantime i have decided to populate the board according to the manual .All is working properly .

Thank you Russ and Brian for making this project possible .

Oh and ... wktl_smile... thanks for you output on this , it's is noted .
The sound signature is different with and without the BAL/SE section , might revert back and find proper output caps to eliminate residual noise which is quite minimal really .
regards to all

 

[zajin]

Hi Russ.
When I buy legato III with buffers, can I have a signal from op amp (to amplifier) and from buffer (to headphones) simultaneously? Or may be it is possible to install any switch
to switch the circuit from opamp to amplifier and from buffer to headphones? Does the buffers (their loops to op amps) makes any load to op amp and have influence on them? (I mean on their sound).
thanks
and regards

wondering the same myself. I mostly use my Buff II connected to SE amp, but I would like to have good headphone drivability too.

 

[BrianDonegan]

Hi Russ.
When I buy legato III with buffers, can I have a signal from op amp (to amplifier) and from buffer (to headphones) simultaneously? Or may be it is possible to install any switch
to switch the circuit from opamp to amplifier and from buffer to headphones? Does the buffers (their loops to op amps) makes any load to op amp and have influence on them? (I mean on their sound).
thanks
and regards

Simply drive both from the buffer outputs. There is no downside there.

 

[Russ White]

Make sure you understand the schematic. The buffer is in the feedback loop of the op-amp. They are a unit, it is not a separate circuit.

 

[AudioDAC]

Hi Russ.
Thanks for your reply.
So, what would you suggest, to buy Legato with buffers or without?
I will be mainly use it with high and amplifier with loudspeakers, and rare with headphones if any.
I think that such buffer will have an influence on the sound and parameters of the circuit.
In my experience, every additional component in the signal path, like such integrated buffers (small current amplifiers) makes additional THD and noise rise in the signal.
And if it is not necessary in the circuit it is better to omit it.
Did you measure THD of Legato 3.1. with buffers?
I would be very grateful for your recommendation.
Andrzej