bypass caps

aragorn723 · 7300

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Offline aragorn723

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Reply #15 on: January 10, 2015, 01:29:06 PM
Funny thing about the black gate caps - apparently they are electrolytic?  Some of the Quickies on this site had film caps for the 150 uf cap, I guess the black gate option is a more cost effective one?  (haven't seen any inexpensive film caps, they seem to be rated for high voltages).  Of course this is subjective, but would the quality of the sound be that much better in film caps vs. the black gates?  (Maybe in terms of value the black gate is the way to go).  This would just be a simple remove and replace of the existing 150uf cap, right?

Dave
« Last Edit: January 10, 2015, 01:31:09 PM by aragorn723 »



Offline mcandmar

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Reply #16 on: January 10, 2015, 01:39:10 PM
Yes they are lytics, and many people swear they were the best ever made.  How much of that is true, and how much of that is mythology i dont know.  There are a plenty of other options from Panasonic, Nichicon, and Elna that may be as good, if not better.

Poly film caps are also an option, but they are more expensive, and physically very large. Most 200uf poly caps are the size of a beer can!

M.McCandless


Offline aragorn723

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Reply #17 on: January 10, 2015, 01:44:11 PM
For $2.37 a piece, it's worth a shot!  Do I just take out the old caps and pop in the new ones the same way?

Dave



Offline mcandmar

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Reply #18 on: January 10, 2015, 02:06:36 PM
Yes just a straight swap.  Before you do measure the voltage across those caps and make sure its under 4v, ideally under 2v.  Mine has been modded a bit so i cant use mine as a reference.

M.McCandless


Offline aragorn723

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Reply #19 on: January 10, 2015, 05:08:47 PM
The voltage is reading 1.5V.  Wish I had changed these before putting in the k75's, would have been much easier  ::) 



Offline 2wo

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Reply #20 on: January 10, 2015, 07:48:22 PM
for 3 bucks, go for it. Satisfy your curiosity, (and ours).
I am talking about the cathode bypass cap here.

If you decide to make changes. Before you put a new cap in, play it with no cap at all. That will give you a sense of what it does and its effect on the sound...John
   

John Scanlon


Offline aragorn723

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Reply #21 on: January 11, 2015, 01:57:45 AM
If i'm looking at the schematic correctly, there are 1k resistors in parallel with the 150uf caps, so this would eliminate the need to add a jumper when running the Quickie without the cap.  Could it damage something by not having the cap? 

Dave



Offline mcandmar

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Reply #22 on: January 11, 2015, 11:13:29 AM
The voltage is reading 1.5V.  Wish I had changed these before putting in the k75's, would have been much easier  ::)

Just resurrected my PJCCS quickie and i'm seeing ~1.75v across the caps so it seems comfortably below the 4v rating.  Let us know what you think when you get them fitted..

M.McCandless


Offline aragorn723

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Reply #23 on: January 11, 2015, 01:35:13 PM
Should be interesting.  The blackgates have a big following, some think they are the best caps ever made.  Would changing these make a big difference in sound?  Might have to order a set of these tonight.

Dave



Offline aragorn723

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Reply #24 on: January 14, 2015, 03:01:40 PM
They were changed to 150uf in the Quickie v1.1.  From memory it only sees 2-3v in normal operation, Partsconnexion list 220uf 4v Blackgate caps for $3 each which i always wanted to try in that position, though somehow i seem to forget about it every time i place an order.

Do they normally take a few days to fill orders?  I place an order with partsconnexion Monday, and got a confirmation..  No word on shipping yet.

Dave



Offline mcandmar

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Reply #25 on: January 14, 2015, 03:05:35 PM
I have no idea, i'm in Ireland so anywhere i order from takes a month to get here, hence i pay no attention to processing/shipping times :)

M.McCandless


Offline aragorn723

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Reply #26 on: January 20, 2015, 03:39:02 PM
I guess a few days to fill the order isn't bad for something that is out of production.  Just got an email that they shipped.  For the money, it should be a fun experiment!  How long do these take to break in?

Dave



Offline Grainger49

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Reply #27 on: January 21, 2015, 02:18:45 AM
Dave,

I agree, PCX has an odd procedure.  They acknowledge your order.  Sometimes ask for verification, then ship a few days later.  But I believe it is a small operation.  I have always gotten good service from them.



Offline aragorn723

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Reply #28 on: February 05, 2015, 03:45:59 PM
Hi everyone,

Just wanted to say I got the black gates in!  The Quickie improved somewhat without the bypass caps-it opened up the treble/detail, but it sounded grainy.  With the black gates in, the effect was similar, but the sound is very smooth.  There are some moments when the guitars sound reallly goood, can't wait to try that out more.  The details are a lot more defined, and the edges of fine detail sounds really good too.  Overall, it is a very noticable improvement over stock. 

Dave