We all suit ourselves, no? The newest version of Placid HD BP (v.2.1) is very nice - quiet with practically zero thermal drift. For Legato it performs up to the standards I want to hear.
I appreciate Russ & Brian's "sensible" parts choices - mindful of value and with insight that I lack. In this case, yes, I'm just trying to hot-rod a circuit to customize the response to personal preference. ... a final tweak... Throwing out the power supply would be like starting over!
I thought 100uF is a lot already, but - let us know if you got any improvements! I still have quick connects soldered so i can swap caps quickly - i'll try it too, not sure if i'll be able to hear a lot of difference, but we'll see
My build is so tightly packed that (dis)assembly is a significant job. Thus, I just 'went for it' and put everything in rather than testing after individual changes. Not good science but the job is done and first listening tests are favorable.
On all boards:
C9, 10, 13 & 14 went to 220 uF Panasonic FM
C1-4 & C19-22 went to polystyrenes [source]
C15 & 16 bypassed by MKP1837s
On the L3.1 board for bass (=<200Hz):
C15 & 16 changed to 220 uF Panasonic FM (plus MKP1837 bypass)
First listen: This is good! Everything has a clearer location in space, and acoustics of recording sites are much more evident. String sections, choral voices, etc. all have more personality and resolution. This effect matches what I experienced when I put polystyrenes in the L2, only it is enhanced by the pristine signal coming out of Cronus. The other question was, what about the bass? Also good! It is clearly more dynamic, forceful, and clean. Examples - a) with walking jazz bass you can hear more nuances of the bass viol's tone and SQ, b) the force of a kick drum is undiminished coming through a heavy electric bass line - the drum beat can really hit you in the chest. These effects may be somewhat transducer-dependent - my woofers are fairly efficient with excellent resolution [JBL 2235h's in 5 cu. ft.]. For bass, I'd conclude that 220uF is not wasted in positions 9,10,13-16 of Legato 3.1.
Cheers,
Frank
Good thing there's improvement, just not sure how much the increased decoupling helped and if it's not mainly effect of polystyrenes... When increasing capacitance of same cap type you can hear changes from doing so, but when you change anything else to other capacitor type you get different sonic signature and then it's nearly impossible to tell... Anyway - good thing i still haven't tried the polysterenes so i can simply double the capacitance by soldering another 100uF under the board and see if it will change thing or two...
I, however, already did so with elna silmic II and heard slight but noticeable difference. Which is logical due to impedance drop...
Thanks, i guess one more cap tweak to mess with before i put everything into box myself
I, however, already did so with elna silmic II and heard slight but noticeable difference. Which is logical due to impedance drop...
Thanks, i guess one more cap tweak to mess with before i put everything into box myself
Correct, so I'll be interested in your isolated results. I just don't have the best setup for checking each single mod. I imagine the 1837s at C15 & 16 contribute more goodness than the 220uF electrolytics. All together, though, I'm very pleased with the upgrade... BTW, on the bass board I even raised the shunt current to ~95 mA, since heat is no problem in my chassis. After a few weeks of 'burn-in', I'll play with current overhead to optimize...
Thanks, i guess one more cap tweak to mess with before i put everything into box myself
Enjoy!
Hmmm I got one question regarding the legato...
Iḿ using an quanghau design DAC together with the legato I/V stage....
After startup the USB is active, and when I switch to optical input I can see that signal is locked, but there is no sound coming from the legato.
After switching off and on the legato stage, there is sound. Do u have an idea why this is ?
Iḿ using an quanghau design DAC together with the legato I/V stage....
After startup the USB is active, and when I switch to optical input I can see that signal is locked, but there is no sound coming from the legato.
After switching off and on the legato stage, there is sound. Do u have an idea why this is ?
I did because friend found they was oscillating and I built other Buffalos without Placid with much better results. Teddy Pardo for digital,
Belleson mini for Avcc, Tridents are ok now.
Sorry, was just asking because I was not sure if it is coming from DAc or Legato
My build is so tightly packed that (dis)assembly is a significant job. Thus, I just 'went for it' and put everything in rather than testing after individual changes. Not good science but the job is done and first listening tests are favorable.
On all boards:
C9, 10, 13 & 14 went to 220 uF Panasonic FM
C1-4 & C19-22 went to polystyrenes [source]
C15 & 16 bypassed by MKP1837s
On the L3.1 board for bass (=<200Hz):
C15 & 16 changed to 220 uF Panasonic FM (plus MKP1837 bypass)
First listen: This is good! Everything has a clearer location in space, and acoustics of recording sites are much more evident. String sections, choral voices, etc. all have more personality and resolution. This effect matches what I experienced when I put polystyrenes in the L2, only it is enhanced by the pristine signal coming out of Cronus. The other question was, what about the bass? Also good! It is clearly more dynamic, forceful, and clean. Examples - a) with walking jazz bass you can hear more nuances of the bass viol's tone and SQ, b) the force of a kick drum is undiminished coming through a heavy electric bass line - the drum beat can really hit you in the chest. These effects may be somewhat transducer-dependent - my woofers are fairly efficient with excellent resolution [JBL 2235h's in 5 cu. ft.]. For bass, I'd conclude that 220uF is not wasted in positions 9,10,13-16 of Legato 3.1.
Cheers,
Frank
Hi Frank, changed the caps to Pana FM 220uF and bypassed C15 C16 with small teflon tin foil 15nF, without the bypass lacks definition.
Thanks fo the trick
Felipe
I made another interesting experiment with my Legato to determine if C15/C16 positions are sensitive to ESR or it's something else.
I installed Elna silmic 100uF/25V on one channel, and Panasonic FM 100/25 on the other. Compared the sound - the channel with Elna was smoother and more "musical" i guess, but somewhat lacked bite and attack compared to FM. I could easily tell which channel has which cap (blind)
So i soldered another 100/25 Silmic at the bottom (paralleling 2). And surprise - i could no longer easily tell the difference betwen the channels, the excessive "smoothess" of Silmic II was gone, it became more dynamic and fast. There is some difference, but it's not as pronounced.
The ESR of 100uF/25 pana FM is around 0.13 and Silmic's around 0.22 By paralleling 2 of them i think i dropped ESR to just about panasonic's level which i guess proves that esr/impedance is important in such positions... Unless it's something else, like ESL which should have also dropped...
I'm still not sure about bypassing with film (until extensive measurements) so i'll try Sanyo OSCON SP 270uf in these positions which should combine both very low esr and works very high in frequency on it's own...
I installed Elna silmic 100uF/25V on one channel, and Panasonic FM 100/25 on the other. Compared the sound - the channel with Elna was smoother and more "musical" i guess, but somewhat lacked bite and attack compared to FM. I could easily tell which channel has which cap (blind)
So i soldered another 100/25 Silmic at the bottom (paralleling 2). And surprise - i could no longer easily tell the difference betwen the channels, the excessive "smoothess" of Silmic II was gone, it became more dynamic and fast. There is some difference, but it's not as pronounced.
The ESR of 100uF/25 pana FM is around 0.13 and Silmic's around 0.22 By paralleling 2 of them i think i dropped ESR to just about panasonic's level which i guess proves that esr/impedance is important in such positions... Unless it's something else, like ESL which should have also dropped...
I'm still not sure about bypassing with film (until extensive measurements) so i'll try Sanyo OSCON SP 270uf in these positions which should combine both very low esr and works very high in frequency on it's own...
Last edited:
FYI re the eventual (hoped-for) plus and minus film cap bypass experiment:
Audiophile Musings: The Vishay MKP 1837 Review and Modification
Now that Panasonic FM caps are burned I taked off the bypassed teflon.
Good luck - I hope you are happy with your end point.
My own situation keeps changing - the Placid to the bass Legato started acting up so I am replacing it with HDBP v. 2.1. That will be significantly superior, whether the difference can be heard remains to be seen. Meanwhile, an older midrange driver is just beginning to distort, so I am replacing the pair with higher efficiency units. While I'm at it, new AMT tweeters.
That will significantly extend the system equilibration. Until then, no more changes to Legato - MKP1837s @ 15 & 16 are probably in to stay. Via headphones, the present output is wonderful.
Last edited:
Meanwhile OSCON SP 270uF/10V and BlackGate F 100uf/16V were added to my cap experiements, i also measured ESR at friend's rig. My conclusion so far is that esr and sound do not correlate directly in C15/C16 positions.
The measurements revealed that "audio grade" caps actually have pretty low ESR, at least at 13900Hz with Nichicon KZ almost as low as Pana FM, Silmic II slightly higher (but still a lot better than panasonic FC for example) and 15 years old BG F measuring lower ESR/D/Z than all of them except OSCON SP which had extremely low ESR (but sounded the worst)
As for sound - comparing these one after another my feeling is that caps are just "noisy" to a different degree. With OSCON being the dirtiest and thinnes sounding, while BG-F which is lowest in ESR after it - sound the oppisite - the "darkest" of the group, with least HF shril, harshness and grain. Then Silmic II, then Nichicon KZ, then Pana FM. Each have their own +\- in sound.
So far i decided to leave BG F in there so can get both - good measureable specs and sound without second thoughts
The measurements revealed that "audio grade" caps actually have pretty low ESR, at least at 13900Hz with Nichicon KZ almost as low as Pana FM, Silmic II slightly higher (but still a lot better than panasonic FC for example) and 15 years old BG F measuring lower ESR/D/Z than all of them except OSCON SP which had extremely low ESR (but sounded the worst)
As for sound - comparing these one after another my feeling is that caps are just "noisy" to a different degree. With OSCON being the dirtiest and thinnes sounding, while BG-F which is lowest in ESR after it - sound the oppisite - the "darkest" of the group, with least HF shril, harshness and grain. Then Silmic II, then Nichicon KZ, then Pana FM. Each have their own +\- in sound.
So far i decided to leave BG F in there so can get both - good measureable specs and sound without second thoughts
Last edited:
Good luck - I hope you are happy with your end point.
My own situation keeps changing - the Placid to the bass Legato started acting up so I am replacing it with HDBP v. 2.1. That will be significantly superior, whether the difference can be heard remains to be seen. Meanwhile, an older midrange driver is just beginning to distort, so I am replacing the pair with higher efficiency units. While I'm at it, new AMT tweeters.
I'm using Salas BiB regs to powering the Legato with great success.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.