Hello.
The Legato 3.1 works perfectly. Has lower distortion than IVY-III circuit and sounds better, especially bass.
But the balanced output + and - features 9 v. respect to ground. I will used it with balanced DCB1 and F5X (EUVL).
As one of the advantages of both DCB1 and FX5 will be that will be coupled in continuous, capacitors employment would spoil all advantages.
To solve the problem I can think of two circuits. It is floating mass to set XLR Pin 1 to 9 v.
I have a doubt that will work best of two. And what better 0 to15 v. or -15 to 15 Volts?
The Legato 3.1 works perfectly. Has lower distortion than IVY-III circuit and sounds better, especially bass.
But the balanced output + and - features 9 v. respect to ground. I will used it with balanced DCB1 and F5X (EUVL).
As one of the advantages of both DCB1 and FX5 will be that will be coupled in continuous, capacitors employment would spoil all advantages.
To solve the problem I can think of two circuits. It is floating mass to set XLR Pin 1 to 9 v.
I have a doubt that will work best of two. And what better 0 to15 v. or -15 to 15 Volts?
An externally hosted image should be here but it was not working when we last tested it.
Hmm, I am not sure you will need such a circuit at all. You should just be able to leave pin1 floating or simply GND only one end. In fact it might not be a good idea because if the possibility of a short.
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If I were going to do such a circuit I would simply put a couple of 10K(or similar value so as not to unnecessarily load the output) resistors in series across the balanced outputs and take the center(junction). Then use that for your common mode voltage (buffered). But once again you would have to be sure pin1 never made contact with common GND (say earth GND not necessarily 0V) or you would get a short.
As I said I can't think of a reason you would need to do this.
As I said I can't think of a reason you would need to do this.
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Are you sure Legato has lower distortion than IVY?
I agree that Legato works perfectly, if it sounds better is a matter of taste, but that IVY should be shy or imprecise in bass is certainly not my impression.
I measured the armonic distortion is much lower in my circuit. It is important that they are perfectly united Q2-Q3 and Q5-Q6. This is what more reduces the harmonic distortion in my circuit.
And the bass of IVY was the best and most accurate that had ever heard ... Until I heard the Legato 3.1 on a friend's house.
And the bass of IVY was the best and most accurate that had ever heard ... Until I heard the Legato 3.1 on a friend's house.
Hi Oneoclock.
Hmm this is very interesting to hear. I had an early version of Legato tested by a third party and it measured slightly worse (though only very slightly) in terms of dynamic range, but almost identical in terms of THD as IVY-III. Can you share your results?
Thanks! Russ
Hmm this is very interesting to hear. I had an early version of Legato tested by a third party and it measured slightly worse (though only very slightly) in terms of dynamic range, but almost identical in terms of THD as IVY-III. Can you share your results?
Thanks! Russ
This is the armonic distorsion 1000 Hz. tone measure with my IVY.
7 dB down since the 1000 Hz tone have +7 dBu.
Tomorrow I get the measure of Legato 3.1
7 dB down since the 1000 Hz tone have +7 dBu.
Tomorrow I get the measure of Legato 3.1
An externally hosted image should be here but it was not working when we last tested it.
How are you measuring? Differential? The 3rd harmonic is much higher than I have ever seen before. But this could be because of the higher level.
To give you an idea, this is the result of the testing we had done on the Buf32S which is the same output stage as IVY-III.
1000 Hz. + 7 dBu. measure 7 dB down is correct.
The measures in balanced and unbalanced are very close.
The output level and measurement equipment configuration is identical to IVY
Legato III 3.1
The measures in balanced and unbalanced are very close.
The output level and measurement equipment configuration is identical to IVY
An externally hosted image should be here but it was not working when we last tested it.
Legato III 3.1
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What does that work out to in terms of THD? I am very pleased with the picture so far. 🙂
I am suspicious that there may something wrong with your IVY-III or possibly there are some resistor values that should be tweaked. Because the performance is very far off the mark.
Is there anything different about it from stock? Is it mounted using the mezzanine connectors?
Thanks!
RUss
Get this distortion has cost me effort. The transistors Q2-Q3 and Q5-Q6 have to go well together and touching. I've been moving this until they were good together and lowered distortion. I had -115 (-122) dBu two harmonics one positión but I could not place again.
They should be glued in origin before soldering?
This measure is a Textronix AM700, is worse than a Audioprecisión and may be in poor condition. But compared to other DAC is the best I've ever measured.
Will I try to measure a Buffalo IVY from a friend to see if they look to close Ivy measures than mine. Do not go to be defective.
They should be glued in origin before soldering?
This measure is a Textronix AM700, is worse than a Audioprecisión and may be in poor condition. But compared to other DAC is the best I've ever measured.
Will I try to measure a Buffalo IVY from a friend to see if they look to close Ivy measures than mine. Do not go to be defective.
Yes I placed the patterns back to back specifically so that the Qs could be joined thermally. 🙂 I am glad you picked on that. I will make it more explicit in the manual. I glue mine together with a little thick CA or epoxy.
Great work!
So it seems to me that works out to something between -116 to -118db THD?
Very good. Thanks for sharing!
Great work!
So it seems to me that works out to something between -116 to -118db THD?
Very good. Thanks for sharing!
Well I have been considering a resistor value change in IVY-III. Your testing may help me decide new values along those lines. I really appreciate you sharing your results.
Everything is mounted like regular unity.
The balanced and unbalanced IVY measures had a similar measure.
The balanced and unbalanced IVY measures had a similar measure.
An externally hosted image should be here but it was not working when we last tested it.
What ? New information to and "old" board. Manual says zip 😀
Lid off again - mixing epoxy...
When the two transistor was very closed together, the values oscillates between -115dB to -120dB (15 seconds of period)
Correctly glued will drops to -122 dBu (or less)
I remark, all the values needs to be corrected with 7dB less, -115dBu = -122dBu