I would think that burn in is a one time thing. But, some electrolytics need reforming after years of sitting. Yours I dont think would change over time after initial burn in. I think what you hear is what you will hear unless the electrolytics on your board need a bit more burn in.
ClaveFreman- I have certainly heard different caps change the sound but have really only experienced a difference in bass with power supply beefiness. I had 120kuF on my P2P LM3886 and it seemed to have more, I dont know, assertive.? More authoritative or whatever, but it seemed like there was more control. I have not yet tried huge power supplies on the MyRef and would love to hear someone else's impressions, but I dont think I will be changing mine much. I am however watching your experiments and will probably change the C13 and C21 and I forget the other , but I will most likely try what you find to work best.
The DEQ2496 is here http://www.enjoythemusic.com/magazine/equipment/0705/behringerultracurve2496.htm
Uriah
ClaveFreman- I have certainly heard different caps change the sound but have really only experienced a difference in bass with power supply beefiness. I had 120kuF on my P2P LM3886 and it seemed to have more, I dont know, assertive.? More authoritative or whatever, but it seemed like there was more control. I have not yet tried huge power supplies on the MyRef and would love to hear someone else's impressions, but I dont think I will be changing mine much. I am however watching your experiments and will probably change the C13 and C21 and I forget the other , but I will most likely try what you find to work best.
The DEQ2496 is here http://www.enjoythemusic.com/magazine/equipment/0705/behringerultracurve2496.htm
Uriah
This was my answer to tone control 
I got way in over my head because I saw how easy tone control was and then wanted bigger and better so I was going to build a 24 position equalizer out of LDRs and thats when I got crazy about the Lightspeed attenuator. Definitely use this on your MyRef. The transparency is incredible. So anyway the cost of doing a 24 postition equalizer with LDRs was huge and I started searching for a great commercial equalizer. This fit the bill on paper so I ordered it and its at home. When I get back on the 5th I cant wait to wire it up. It has a microphone that measures and accounts for room response/walls/corners etc.. Its supposed to be real transparent to, but we shall see.
I would do tone control with LDR pots and an AD797 or other high quality opamp. There are lots of simple circuits to do so.
Uriah
I got way in over my head because I saw how easy tone control was and then wanted bigger and better so I was going to build a 24 position equalizer out of LDRs and thats when I got crazy about the Lightspeed attenuator. Definitely use this on your MyRef. The transparency is incredible. So anyway the cost of doing a 24 postition equalizer with LDRs was huge and I started searching for a great commercial equalizer. This fit the bill on paper so I ordered it and its at home. When I get back on the 5th I cant wait to wire it up. It has a microphone that measures and accounts for room response/walls/corners etc.. Its supposed to be real transparent to, but we shall see.
I would do tone control with LDR pots and an AD797 or other high quality opamp. There are lots of simple circuits to do so.
Uriah
udailey said:This was my answer to tone control
I got way in over my head because I saw how easy tone control was and then wanted bigger and better so I was going to build a 24 position equalizer out of LDRs and thats when I got crazy about the Lightspeed attenuator. Definitely use this on your MyRef. The transparency is incredible. So anyway the cost of doing a 24 postition equalizer with LDRs was huge and I started searching for a great commercial equalizer. This fit the bill on paper so I ordered it and its at home. When I get back on the 5th I cant wait to wire it up. It has a microphone that measures and accounts for room response/walls/corners etc.. Its supposed to be real transparent to, but we shall see.
I would do tone control with LDR pots and an AD797 or other high quality opamp. There are lots of simple circuits to do so.
Uriah
I was interested in doing the DEQ2496 and the XO version but I could never find out if the signal could stay digital between the two units or if it had to repeat ad to da conversion..
udailey said:
Uriah, caps made a difference also on bass in my tests, not night and day differences but clearly audible ones
; I've just started preparing C13 benchmark:An externally hosted image should be here but it was not working when we last tested it.
Also C13 influence bass, I've tryed so far:
- DC Coupled: the reference
- Evox-Rifa PHE426 1uF 250V
- Arcotronics/Kemet R46 1uF 275V X2 (the ones in kits)
- Elna Silmics x2 (forming a bipolar elco)
First impressions:
- R46 are nice but, like AVX BQs, somewhat 'restricted' with less soundstage and openness, uninvolving and, oh, they limit bass seriously!
- PHE426s are, as I was hoping, quite good: soundstage is 97% there, openness and bass too
but they lack the ultimate bit of clarity, doubling the value makes bass 99% there - Silmics in bipolar configuration are surprisingly good: very musical, soundstage and bass are there but they seriously lack in openness and clarity, a MKS2 bypass helps.
- MKP1837 bypass isn't good here too, it restricts soundstage
- MKS2 bypass is quite good but I prefer without it, Silmics are an exception.
Now I'm waiting for Wima MKP10s and investigating some others to order...
ClaveFremen said:
Uriah, caps made a difference also on bass in my tests, not night and day differences but clearly audible ones
An externally hosted image should be here but it was not working when we last tested it.
Also C13 influence bass, I've tryed so far:
- DC Coupled: the reference
Now I'm waiting for Wima MKP10s and investigating some others to order...
I'm guessing that to DC couple,you just remove C13? Is there any risk to the amp in DC coupling?
marc brown said:
No Marc, basically you short C13 or, if you prefer, you swap C13 with a wire.
DC coupling remove DC protection from your amp.Until your pre has output coupling caps you're quite safe but if they shorts for whatever reason (like a mod made by yourself
) or you branch to your amp a pre or CD player that has a DC offset: BOOM!The risk is to destroy your woofers...
Obviously DC coupling is the best cap at all (no cap!) and sound wise the difference could be huge but also the risk is huge...
Dario,
You made a nice test rig there, but you must be aware that the extra wire leads and sockets will probably have some affect on the ultimate sound. As long as it's the same for every test, your results are valid relative to each other, but, of course, none of them will sound the same as directly shorting C13 with a wire. However, the sound might change again, and I'm guessing for the better, when you put the caps you finally select directly into the circuit without all the test equipment.
I found that C13 does affect the bass. Certainly the value, but also type of cap. Too large a value is not necessarily better, which is what Andrew described in his post. Too small a value is certainly not good. Right now I'm using 1.0uF, and that is giving me the best bass so far. Originally, Mauro specified values between 0.47 and 2.2uF.
I am looking forward to hearing more about your tests.
Peace,
Tom E
You made a nice test rig there, but you must be aware that the extra wire leads and sockets will probably have some affect on the ultimate sound. As long as it's the same for every test, your results are valid relative to each other, but, of course, none of them will sound the same as directly shorting C13 with a wire. However, the sound might change again, and I'm guessing for the better, when you put the caps you finally select directly into the circuit without all the test equipment.
I found that C13 does affect the bass. Certainly the value, but also type of cap. Too large a value is not necessarily better, which is what Andrew described in his post. Too small a value is certainly not good. Right now I'm using 1.0uF, and that is giving me the best bass so far. Originally, Mauro specified values between 0.47 and 2.2uF.
I am looking forward to hearing more about your tests.
Peace,
Tom E
madisonears said:
Thanks Tom
Obviously you're perfectly right, sockets and wires changes inductance and other things but my objective is to compare caps in a relative way; when they finally will be soldered on pads I'm confident too that they'll sound even better
madisonears said:
I'm quite satisfied too with 1uF PHE426, but I've ordered these Wimas that should be even better, but are available in 22mm ls only as 2,2uF...
Low frequency tone.
Hi Dario,
Subjectively judging a low tone can't be easy.
In the meantime, I have seen the error of my ways. I am trying to change the power amp to correct short-comings in my setup.
The only thing between my Sony DVP-NS900V and the MyRef is a very cheap (€2.50) 10K log pot and some household wiring. Maybe I should get that right and then wait for you guys to test all those caps. I don't know how you get hold of all these samples. You must have freinds in high places.
Hi Dario,
Subjectively judging a low tone can't be easy.
In the meantime, I have seen the error of my ways. I am trying to change the power amp to correct short-comings in my setup.
The only thing between my Sony DVP-NS900V and the MyRef is a very cheap (€2.50) 10K log pot and some household wiring. Maybe I should get that right and then wait for you guys to test all those caps. I don't know how you get hold of all these samples. You must have freinds in high places.
Well, Dario, I wasn't expecting the samples to be free and this exercise must be costing you a packet. Nevertheless, I did the rounds of the suppliers in Nantes the other day and as soon as I asked for anything out of the ordinary, they all said there was no market and they no longer stocked. I can't even find an Alps pot (even if they don't do a 10K). That's why these Group Buys are so interesting and why we should aplaud Uriah and the others.
Tony X said:
here it's the same and not only for electronic components.
If you want something that it's not mainstream you must buy online...
Surely GB are interesting, particularly those like this one, for components you can buy online.
Peter and Uriah obviously deserves our gratitude
ClaveFremen said:
I've tried.
with tones is quite impossible...
With bass notes (AC/DC - Ride On and Bublé - Fever) at full volume (0db attenuation) at near field I would confirm my subjective impressions, differences are not night and day but audibles.
The 'body' of the note with R46 is not as big as DC coupled or PHE426, IMHO
You could try by yourself temporarily shorting C13
att'n: only if you're SURE your pre/cd has NO DC OFFSET!!!! Measure it! )