|Solid State Talk all about solid state amplification.|
Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
||Thread Tools||Search this Thread|
|15th April 2013, 03:41 PM||#1|
Join Date: Apr 2005
Location: Cheltenham, Glos.
Recapping Quad 99 - simple question..
Hi there. I've completely re-capped my Quad 99 Pre-amp with new, low impedance low leakage devices. All is well.
However, on the board, I noticed some electrolytics rated 10uf at 50v which were green in colour and clearly have no "+" or "-" [on the cap or the pcb]
I'm making an assumption they are NP electrolytics ? They are physically the same size as the standard electrolytics on the board (I replaced all 10 of them plus plenty of others...)
All of the caps I changed were in the power supply, but these look like they are in the signal path.
Assumption 1:- If I change the cap value, something might happen to the sound
Assumption 2:- as they are in the signal path, that is not always a good thing
Assumption 3:- I can bypass... with a link.. but it's a risk
If I wanted to "upgrade" the quality of the cap, what type should I shoot for ? Tantalum ? Polypropelyne ?
Any thoughts ?
The older I get, the fitter I was !
Last edited by clubsport911; 15th April 2013 at 03:45 PM. Reason: additional Q
|15th April 2013, 04:39 PM||#2|
If they had no polarity markings then its safe to assume they are bi-polar electros.
If you change the value of any cap in a signal path then the response is altered in some way depending on the time constants in the circuit. If you make the cap larger the low frequency response is extended. That can be a problem if the circuit has a "settling time" and larger values of C cause it to make thumps/noises on power on and off. That's just one reason.
I wouldn't bypass any with a link unless you have the circuit to look at to see what they actually do. And just because they are bi-polar doesn't mean they have no static DC conditions across them.
I would think anything other than an electro would be too large physically. A definite NO to tants
Installing and using LTspice IV. From beginner to advanced.
Help for Ruth & Dave
|Thread Tools||Search this Thread|
|Thread||Thread Starter||Forum||Replies||Last Post|
|Quad 99 Tuner problem||barrymagrec||Analogue Source||10||26th January 2012 06:53 AM|
|Quad 99 CDP schematic needed||KevinLee||Digital Source||2||23rd January 2012 04:37 PM|
|FS: Quad 99 Power Amp - Black||datawolf||Swap Meet||0||16th November 2010 11:48 AM|
|QUAD 99 POW problems||kevvywevvywoo||Solid State||10||23rd September 2010 08:55 PM|
|Quad 99 Cdp||JRKO||Digital Source||4||19th August 2004 05:21 PM|
|New To Site?||Need Help?|