[BrianDonegan]

Ivy manual is now posted:
http://www.twistedpearaudio.com/docs...manual_2.0.pdf

 

[dgbiker1]

Thanks Russ!
EDIT: Thanks Brian for the manual too

 

[penger]

So just to clarify, you need 3 IVY boards to have both SE and Balanced outputs?

 

[Russ White]

Quote:

Originally Posted by penger /img/forum/go_quote.gif So just to clarify, you need 3 IVY boards to have both SE and Balanced outputs?

Only if you are running Opus or COD in dual mono setup. If you your running stereo you only need one.

You can actually just take the +OUT and GND to get SE outputs instead of adding one more IVY but it will be -6db and the DNR/THD will not be quite as good.

Cheers!
Russ

 

[sleepy dan]

Hello Russ,

Do you find the Opus sounds better with the IVY, compared to running it's outputs direct?

I'm simply curious, because as you know the IVY will present a more difficult load (although still within spec) to the Opus compared to the input Z of a typical pre-amp. Usually if a voltage follower sounds better it's regarded as due to its presenting an easier load to the source.

Cheers,
Dan

 

[mwofsi]

Quote:

Originally Posted by BrianDonegan /img/forum/go_quote.gif Ivy manual is now posted: http://www.twistedpearaudio.com/docs...manual_2.0.pdf

Hello Brian and Russ.

What's going on in the diagram on page 8 of the pdf manual?

It shows a Ballsie going to two IVYs but the IVYs seem to me to be completly bypassed? They are labelled "Normally Configured MONO IVYs"

 

[Russ White]

Quote:

Originally Posted by mwofsi /img/forum/go_quote.gif Hello Brian and Russ. What's going on in the diagram on page 8 of the pdf manual? It shows a Ballsie going to two IVYs but the IVYs seem to me to be completly bypassed? They are labelled "Normally Configured MONO IVYs"

There is no ballsie involved. Those are Three IVYs.

The two IVYs on the right are configured for mono DACs (either Opus or COD). They have balanced only outputs.

The IVY on the left is simply doing balanced to single ended conversion. This way you can have SE outputs that are the sum of balanced output at the same level as the balanced output. The best way to get a clean SE signal is to sum the balanced signal.

The text expands on this a bit.

Cheers!
Russ

 

[mwofsi]

Thanks, got that now

 

[Russ White]

Quote:

Originally Posted by sleepy dan /img/forum/go_quote.gif Hello Russ, Do you find the Opus sounds better with the IVY, compared to running it's outputs direct? I'm simply curious, because as you know the IVY will present a more difficult load (although still within spec) to the Opus compared to the input Z of a typical pre-amp. Usually if a voltage follower sounds better it's regarded as due to its presenting an easier load to the source. Cheers, Dan

Hi Dan,

The 2K load the Opus sees presents no problem at all, and the additional filtering/summing(in dual mono) of the IVY does help.

Also using the IVY allows you to drive headphones. Which is what many people here will do.

So yes, I use the IVY with Opus even into a poweramp with 100K impedance.

It just sounds better with it than without it.

Cheers!
Russ

 

[Russ White]

Technically you can use a single IVY even for a dual mono Opus setup by putting a sereis resistor (10-221R is fine) at the outputs of the Opus, and wiring like you would a mono Ballsie. But I would personally not recommend this as you lose a lot of the benefit of dual mono operation this way. Which is to say you won't get as good THD specs, or as much common mode noise cancellation.

For dual mono COD this does not apply, you need two IVYs for I/V, and one for BAL/SE if desired.

:EDIT: actually, I am sure single IVY can be done with COD, but with no load sharing resistor, but you would need to recalculate the I/V gain resistor and filter cap, and I have not listened to this configuration or tested it, so I hesitate to recommend it yet as it drops the feedback resistor to a value that is less optimal for the THS.:/EDIT:

Cheers!
Russ

 

[sleepy dan]

Cool.

 

[penger]

Here you are still answering questions... on vacation my butt!

Thanks, by the way.

 

[TimJo]

Cool, just printed the IVY manual. Thanks for the link.

Enjoy some time off!

 

[koike]

hi guys. sorry to intrude.
but i would like to know what is the main difference between the opus and the buffalo?
what are the sonic differences between them?

 

[dgbiker1]

I just spent the day laying out my build and I'm in a bit of a pickle with the power section. My case has a small shielded compartment that makes for a tight fit w/ 2 power supplies, 2 transformers, and the input box. I'm a bit torn with transformer placement.
OPTION 1: Transformers side-by-side. The only thing that worries me is how close the middle tranny gets to the power supply (~1cm from the heatsink). Seems like it could add some noise to the DC output.

OPTION 2: Stack the trannies. I've never seen it done, but it seems like it wouldn't hurt anything. As long as I stack them the right way (in-phase) with the foamies in between, shouldn't this be okay? It seems better since it puts more space between the power supply and the tranny, but I just want to get other opinions since I've never seen them stacked before.