capacitor question?

[JimC]

there £90 each!

[sq225917]

Long leg is positive

[the_doc735]

Long leg is positive

you confirmed my suspicions, is it also slightly thicker?

[Light Dependant Resistor]

Thank you for your help, much appreciated!

Output capacitors will be upgraded to Oil capacitors (with larger uF as suggested by Cary themselves - better bass).

I have been soldering for about 44 years with 'parrot fashion' guidance, in computers, amps, TV's etc.

I was going to ask about polarity, there are no + - signs on the caps?

Also, how to discharge any voltage/current in the DAC, BEFORE doing anything!!

This DAC has had several output caps in its history, Panasonic, Modwright, Monacor, Dynamicap, etc. as well as several makes of valve!! LOL.

Hi Paul
Good to see 44 years behind the iron, the best capacitor for audio really is one not having polarity
as polarity infers a change of phase, I suspect the original Cary and the replacement are
non polarized as coupling audio in a Dac should not involve phase change.

To safely dissipate capacitors in a valve, I would having waited 12 hours measure with a multimeter
set for DC range the voltage existing between 0v and the anode side of the capacitor. 0v can and
does take many forms as the chassis is safety earth that sometimes is not the potential of the
0v point on the circuit board. But the chassis is a good primary spot to place the negative probe
Your probes need to be good ones with ideally 1000v insulation ( most but the very cheapest are OK )

So after 12 hours voltage should be a lot lower. Anything lower than 30v DC is not harmful to touch
so you are right to go. But lets say there is some resident voltage a bit higher.

In this case using a piece of insulated wire with a well insulated clip soldered to a 1 watt 10k resistor, that at all exposed parts
is WRAPPED 6 times IN INSULATION tape, you can carefully then have one end grounded to the chassis and carefully
use the clip to engage the valve end of the capacitor.

ALWAYS BE AWARE AND ONLY HOLD -WHERE THERE IS INSULATION - PARTICULARLY THE CLIP- observing its
insulation abilities.

A Oscilloscope probe has the right design namely a clip that extends out only when needed.
A bit of preparation work is needed to make two such clip leads insulated with resistors one at 10k and the
other at 680 ohm - but handy to have for such work.

Leaving for a minute then use a 680 ohm resistor same method. Voltage then will be
much lower after a minute- so test again with your meter ensuring voltage is below 30v DC .

AT ALL TIMES HAVE THE CARY DAC OFF

The T model has a timer circuit which is very likely to have thermistors and probably
a 555 timer circuit that already dissipate DC. But better being prepared as they may
not have for-seen customers changing capacitors.

Likewise the capacitor being placed in make sure it has no voltage - very unlikely.

Cheers / Chris

[the_doc735]

just got this:

Hello Paul.

I think you are looking at the output coupling caps.

Sure. As long as you can make them fit.

There's no real voltage there that needs that high a voltage cap. It's just what those caps come as. A Mondorf will sure improve the sound!

Technical Support available from 1-5 pm Mondays through Thursday. Closed Fridays

Dan Wemmer | Lead Technician & Technical Support

CARY AUDIO
6301 Chapel Hill Road | Raleigh, NC 27607
919-355-0010 PHONE
919-355-0013 FAX
www.caryaudio.com
[www.carydirect.com][www.carydirect.com www.carydirect.com SHOP NOW!

[the_doc735]

Hi Paul
Good to see 44 years behind the iron, the best capacitor for audio really is one not having polarity
as polarity infers a change of phase, I suspect the original Cary and the replacement are
non polarized as coupling audio in a Dac should not involve phase change.

To safely dissipate capacitors in a valve, I would having waited 12 hours measure with a multimeter
set for DC range the voltage existing between 0v and the anode side of the capacitor. 0v can and
does take many forms as the chassis is safety earth that sometimes is not the potential of the
0v point on the circuit board. But the chassis is a good primary spot to place the negative probe
Your probes need to be good ones with ideally 1000v insulation ( most but the very cheapest are OK )

So after 12 hours voltage should be a lot lower. Anything lower than 30v DC is not harmful to touch
so you are right to go. But lets say there is some resident voltage a bit higher.

In this case using a piece of insulated wire with a well insulated clip soldered to a 1 watt 10k resistor, that at all exposed parts
is WRAPPED 6 times IN INSULATION tape, you can carefully then have one end grounded to the chassis and carefully
use the clip to engage the valve end of the capacitor.

ALWAYS BE AWARE AND ONLY HOLD -WHERE THERE IS INSULATION - PARTICULARLY THE CLIP- observing its
insulation abilities.

A Oscilloscope probe has the right design namely a clip that extends out only when needed.
A bit of preparation work is needed to make two such clip leads insulated with resistors one at 10k and the
other at 680 ohm - but handy to have for such work.

Leaving for a minute then use a 680 ohm resistor same method. Voltage then will be
much lower after a minute- so test again with your meter ensuring voltage is below 30v DC .

AT ALL TIMES HAVE THE CARY DAC OFF

The T model has a timer circuit which is very likely to have thermistors and probably
a 555 timer circuit that already dissipate DC. But better being prepared as they may
not have for-seen customers changing capacitors.

Likewise the capacitor being placed in make sure it has no voltage - very unlikely.

Cheers / Chris

Excellent advice!

Where can I buy clips, leads & resistors to withstand 1000 volts?
these any good? http://www.ebay.co.uk/itm/MERCURY-Al...3D182438870594

I have 3 different multi meters, several soldering irons and a USB oscilloscope & USB microscope. static wrist straps, electronic work platform, probe type thermometer, etc. Thanks for the tips on the insulated clip leads; really neat

[RothwellAudio]

You can eliminate all the guesswork and waiting for hours etc. - just measure the voltage with a mulimeter
Of course, that may be easier said than done. If the main reservoir caps are PCB mounted it might not be so easy to get at the terminals, but the principle is sound. Don't guess - measure.

[the_doc735]

You can eliminate all the guesswork and waiting for hours etc. - just measure the voltage with a mulimeter
Of course, that may be easier said than done. If the main reservoir caps are PCB mounted it might not be so easy to get at the terminals, but the principle is sound. Don't guess - measure.

oh yes, I would always measure anyway, just like my mains tester screwdriver! LOL

[the_doc735]

the problem is SIZE the current monacors are 17mm dia. X 31mm long (quite small). Whereas things like the Audyn 4.7uF 600Vdc Tri-Reference Capacitor are 40mm (diameter) x 60mm (length); somewhat of a disparity in SIZE!! for example. I can't seem to find any posh caps that small. in effect they are twice the width and length in general. Does anyone know of something that will fit the space?

P1070254.jpg
P1070253a.jpg

Possibly this one: https://www.hificollective.co.uk/cat...or-p-8505.html

[the_doc735]

Better............................

http://www.ebay.co.uk/itm/Mundorf-MC...cAAOxydgZTJXt7

Anyway, aside from price, I think it's too big: SKU: SUPS0-230: Body dimensions: 46mm (diameter) x 71mm (length)
...the current ones are only Ø 17 mm x 31 mm long, and that is just about max'd out in the allocated space on the board!

P1070254.jpg
P1070253a.jpg