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Buffalo II - Assembly for the Electronically Bewildered.

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I just upgraded from a Placid BP to a Placid HD BP with no other changes to the Buff II / IVY III. Having listened for less than an hour, I'm very impressed. Depth and detail are improved to the point where I'm hearing stuff I've never heard before. Better still, there's a sense of more energy. It's not louder. It's just that there's more (!?).

FWIW, I'm running +/- 15V and 100mA shunt. Source = Oppo BDP-83 via digital feed.
 
That's good to learn flashgo. I've got a Placid HD BP, Legato 3.1 & Buffalo II in the post but as I can't get my hands on another set of Tridents at least I can feed the habit a bit with those two into my existing Buffalo. 2nd Placid HD BP & Legato 3.1 on preorder.
 
I am waiting for Placid HD BP and i am little frustrated because Tridents are "out of stock" since many weeks ...
 
Had a good listen to the Legato III via SE output through Stax amp/phones and after some burn in the verdict is that IMHO the III is a fair bit better that the II. It appears to pull out more detail (good ond bad) from the mix, with a more palpable 'being there' feel. For example, listening the disc 3 of the Genesis archives set (the Gabriel sets), it is the closest I have got to it sounding like a live concert. There is still a little more edge than the II, which is likely the II giving a more polite sound, rather than the III being inaccurate. Bass is also pheonomenal.

The only mods I made were to use OS-CONS for the PS caps on the boards as well as using a metal can version of the LME opamp. (Same mods as for the Legato II)

Next step is to switch the Placid BP for the newer BP HD version, but that involves some major case surgery.
 
Suffolk Tony said:
La la la LAAA.... Not Listening......
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It depends what version of the Legato 2 Martin had. The later versions of the 2 like yours have the same tp0604 as ver3. There are other differences but you are probably part way there.

My version 1 has used your spare TP0604 tripled up and I like to kid myself it is part way to the 3 :cool:
 
Oh silly me (must be getting senile...) I've just reread the post; thought it was referring to the Mk III Buffalo!!

Yipee! I've got two 3.1 Legatos on the way!
 
James Evans said:
Martin, have you tried it with stock caps in place of the oscons? I wonder what effect, if any, they're having.
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No, unfortunaley I didn't try either the Legato 2 or 3 with the stock PS caps, I wanted to mess with the boards as little as possible, and my logic was that the OS-CONS should out perfrom the normal electrolytics (plus I had a bunch on hand).

My Legato 2 was the early version, and I had not changed out the transistors . I hadn't realised that there were any updated v2 boards as the new transistors had a different pin out.
 
MartinC said:
Had a good listen to the Legato III via SE output through Stax amp/phones and after some burn in the verdict is that IMHO the III is a fair bit better that the II. It appears to pull out more detail (good ond bad) from the mix, with a more palpable 'being there' feel. For example, listening the disc 3 of the Genesis archives set (the Gabriel sets), it is the closest I have got to it sounding like a live concert. There is still a little more edge than the II, which is likely the II giving a more polite sound, rather than the III being inaccurate. Bass is also pheonomenal.....
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After a run-in period Martin I agree with you. The 3.1 has more of everything. Whether that's the V3 alone or the V3 in combination with the HD, I can't say. Awesome playing combo..
 
Ok, legato 3.1 in place (still on old placid bp for the moment). I have fizzing and crackling on SE out on both channels after a few mins. Thoughts on things to check?

On balanced I don't, although I am getting occasional pops and rustles - am I correct in assuming this is dc offset drift and that I should put caps in place? (arse if so)

Music is playing on both SE and balanced out I should add.
 
James, did you reset the shunt current and output voltages on the Placid? The change in load could affect these.
 
Yup, although I could only get 360mV on +ve side of placid (+-15v). Not sure if that would affect it, but it is close. There's no voltage drop in operation.

I know with legato 2 someone posted on the tpa forum about crackling noises (avr had same issue) and it turned out to be the 1watt resistors. I'm going to swap out these ones for the ones from my legato 2 board and see what difference I get.

Not sure if the balanced issue is related - that sounds more just like dc offset. Be a shame to have to install coupling caps.
 
James Evans said:
Ok, legato 3.1 in place (still on old placid bp for the moment). I have fizzing and crackling on SE out on both channels after a few mins. Thoughts on things to check?

On balanced I don't, although I am getting occasional pops and rustles - am I correct in assuming this is dc offset drift and that I should put caps in place? (arse if so)

Music is playing on both SE and balanced out I should add.
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James,

No such issues here, though I cannot use the balanced output as my Stax amp doesn't like the 7v of common mode DC on the balanced lines. On SE dead silent (except fpor music!) - I would reduce your Placid down to 13v and it should then be able to supply more current. I have mine set at +/-13v and around 50mV of shunt. Russ and Brian say that the L3 doesn't benefit from keeping the supply at 15v as much as the L2.

Regards
 
James Evans said:
I know with legato 2 someone posted on the tpa forum about crackling noises (avr had same issue) and it turned out to be the 1watt resistors. I'm going to swap out these ones for the ones from my legato 2 board and see what difference I get.
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Yes, for sure it was failing resistors causing the cracking noise - but that was in version 1 where it was up to just 1 resistor to dissipate the heat. The v3 (and V2) has twice the amount of resistors to dissipate the same amount of heat.

Perhaps it wasn't due to heat at all the cracking issue appeared? Perhaps it was a crappy resistor.

Back then I changed the resistors and I newer heard the problem again.
 
James, can you measure offsets on both SE and balanced outputs? My first thought if the SE output is the offender is that it's instability in the opamp. But you say balanced out is giving some noises too ....?

Further though, are the noises all the time, or just when you change volume?
 
Balanced is giving rustling with the occasional pop - I'm thinking that sounds like dc drift. SE sounds more like sizzling. Music plays ok, just with background noise. It's not immediate, but after a minute or so of being switched on. I'll retouch all my joints and replace the 1w resistors with the ones I had on legato 2. Offsets on SE and balanced were as near to zero as I could get them, but they did seem to drift by a few points of mV as I held the probes on them for some time.
 
James Evans said:
Balanced is giving rustling with the occasional pop - I'm thinking that sounds like dc drift. SE sounds more like sizzling. Music plays ok, just with background noise. It's not immediate, but after a minute or so of being switched on. I'll retouch all my joints and replace the 1w resistors with the ones I had on legato 2. Offsets on SE and balanced were as near to zero as I could get them, but they did seem to drift by a few points of mV as I held the probes on them for some time.
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DC offset doesn't actually have a sound, although DC across a potentiometer such as a volume control can cause crackling as it's adjusted, but that doesn't seem to be your problem. Hmmm, maybe one of the pots have gone a bit noisy? Try listening on balanced and seem if the rustling happens as you adjust VR1/2.
 
James,

My bet since the effect seems to be time (hence temperature dependent) is that you have a dry joint or a bad resistor lead. Your idea of retouching the joints is a good idea. If that doesn't solve it you could try removing the BUffalo from the Legato and listening to the output as you apply freeze spray to each component. That can sometimes isolate the problem.

Good luck!
 
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