It had to happen eventually... capacitor upgrade question for the Mainline

Loquah · 43897

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Offline swich401

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Looked up some cap ratings online, and the Mundorf Supremes seem to get really high ratings consistently:
http://www.laventure.net/tourist/caps.htm
https://www.head-fi.org/t/284863/orgy-of-capacitors-the-cap-thread
http://www.humblehomemadehifi.com/Cap.html

How many do I need to order? Would there be any benefit from going for 12uF or 18uF instead of 10uF ??



Offline Loquah

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Looked up some cap ratings online, and the Mundorf Supremes seem to get really high ratings consistently:
http://www.laventure.net/tourist/caps.htm
https://www.head-fi.org/t/284863/orgy-of-capacitors-the-cap-thread
http://www.humblehomemadehifi.com/Cap.html

How many do I need to order? Would there be any benefit from going for 12uF or 18uF instead of 10uF ??

You need 2 caps. I'll let others confirm the benefits or different capacities to be certain, but my understanding is that larger capacitance doesn't really help so long as you start at the right level (i.e. too little is bad, but more than enough isn't better).

Can you get some for me while you're at it??  :P

Check out my reviews on YouTube - https://youtube.com/c/passionforsound


Offline Grainger49

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Bottlehead designs for a flat response at or below 20 Hz, but PJ always states a range for Parafeed caps.  Increasing the value of their capacitor will extend the low end.  Whether or not it will be audible depends on a list of factors.

For instance the 18uF will go almost an octave, 8 notes, lower than the 10uF.  PJ urges everyone to experiment and report the findings.



Offline Loquah

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Bottlehead designs for a flat response at or below 20 Hz, but PJ always states a range for Parafeed caps.  Increasing the value of their capacitor will extend the low end.  Whether or not it will be audible depends on a list of factors.

For instance the 18uF will go almost an octave, 8 notes, lower than the 10uF.  PJ urges everyone to experiment and report the findings.


My wallet thanks you for the extra exercise of opening and closing over and over...  ;)

Check out my reviews on YouTube - https://youtube.com/c/passionforsound


Offline swich401

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If I installed a switch to change between capacitors while the Mainline was still on, does anybody see any potential problems associated with this?? I'd be looking to install several caps attached to the switch so that I can do quick A/B testing during operation.

Would a higher capacitance value affect the higher frequencies?



Offline Paul Birkeland

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If I installed a switch to change between capacitors while the Mainline was still on, does anybody see any potential problems associated with this??
Would a higher capacitance value affect the higher frequencies?

I wouldn't recommend the switch.  You'd be switching high voltage DC (even if you switched the cold side of the cap, there will be a charge spike across the contacts) 

The actual construction of the capacitor will influence high frequency tonal balance, but not the actual value itself.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline swich401

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Alrighty, so I am about to order 15uF Mundorf Supreme caps for my Mainline, but before I do I want to make sure I've got this right:

A higher capacitance will not cause a change in the tonal balance of the amp, but could lead to greater low frequency extension ??

Main difference would be the cost difference between a 10uF and 15uF capacitor in this case ??



Offline Doc B.

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We can't tell you that putting in a different cap won't affect the tonal balance. Putting in a larger cap can move the resonance of the LCR circuit, and that can change the shape of the bass response. Going bigger is usually not too much of a problem. But to be sure of what it going on the best thing to do run a frequency response curve. Beyond that different materials and construction can change the sound in different ways and you really just have to smoke it and see.


Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline swich401

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So I ended up getting 10uF Mundorf Supreme caps, which I will burn in (200-300hrs) and do a review on to let others know how they modify the sound of the Mainline.

Question:
Would you foresee any problems if I also tried running both the Mundorf and the Dayton caps in parallel to see how it would sound?? Probably won't run that combo long term, but thought it may be worth a try  ;D



Offline Paul Birkeland

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There's no harm in trying, but I wouldn't expect to be very happy with the results.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Grainger49

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    .  .  .    Would you foresee any problems if I also tried running both the Mundorf and the Dayton caps in parallel to see how it would sound??  .  .  .   

I would add the Dayton with a pair of jumpers.  This is easier and if you like it you can solder them in.



Offline swich401

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Hmm, I prefer the mechanical stability that comes along with a solder joint. De-soldering is relatively easy using a de-soldering braid or pump.



Offline Grainger49

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But PB/CB said it might not be a positive combination.  I'm lazy and take the easier way out. 

I have paralleled/bypassed several dozen caps.  I always make the sonic derision with jumpers because I have to add the cap, remove it, add it, remove it till I am sure of what I'm hearing. 

Of course, I break in my caps first so that isn't a factor.



Offline mcandmar

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I did exactly that when adding a bypass to the power supply in my Quickie, without being able to switch in/out quickly i would never have been able to tell the difference between the cap and my imagination.

M.McCandless


Offline swich401

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Would something akin to the attached image (for each side) work if I wanted a permanent setup where I could switch to one, or both, of the caps on at a time. The switches would only be flipped when the amp was off. Switches would be flipped to discharge when the amp is off to bleed the caps, then switched to the desired setting for which cap I want in the circuit. Would there still be a charge spike across the contacts in this situation if switching was done with amp off?