Ceramic Cap Discussion from Jazz Mode Video Demo With Stratocaster and 102

[erwin_ve]

When looking for DC voltage stress on dielectric found more papers.
Its not only affecting ceramics but also foil capacitors: if it is hearable is another discussion but it's measurable.

[Tony Bones]

Thanks to erwin_ve for finding those documents. For completeness, here is the full set of articles by Cyril Bateman published in Electronics World in 2002 and 2003.

I downloaded them from https://linearaudio.nl/cyril-batemans-c ... d-articles and have included them as attachments here for the sake of persistence.

[Tony Bones]

The rest.

[talbany]

Tony/Erwin
Thanks so much for the additional info. Allot to chew on
Will check them out!
Tony

[10thTx]

I've been using TDK FG caps for a while and have been happy.

So, ………… is there some thought as to which other currently produced ceramic caps are good sounding? Most of the thread has discussed merits & disadvantages of different types of ceramic caps and/or referred to what has been used in the past, but not much mention of specific currently produced ceramic caps that sound good.

With respect, 10thtx

[talbany]

I've been using TDK FG caps for a while and have been happy.

So, ………… is there some thought as to which other currently produced ceramic caps are good sounding? Most of the thread has discussed merits & disadvantages of different types of ceramic caps and/or referred to what has been used in the past, but not much mention of specific currently produced ceramic caps that sound good.

With respect, 10thtx

I think we are treading in new territory here. Another words there is not much info here and within the amp building community regarding the sonic aspects of the various ceramic caps out there with respect to guitar amps(either that or nobody is talking). Most of the conversations revolve around ceramic vs silver mica. I personally believe most builders don't either A.believe or hear there is a sonic difference or B.They just don't bother to do any empirical testing to form an opinion. This is why I asked if this was some kind of breakthrough
So Jeff IMO your better off just installing a pair of transistor sockets in a test amp somewhere in your stable and go through as many as you want to try and form your own opinion. That way maybe if enough of us do this we can then form an opinion here which IMO would be a wonderful resource to draw upon when building our Dumble inspired amps. Myself and Charlie and a few others have done everything we can to try a point out the sonic differences in various parts (New and old) much of which has been met with great skepticism I personally enjoy hearing what type parts sound good to them and want to learn so I dig this kind of discussion!!
Good Luck and keep us posted on what you find.

BTW I think this would best be limited to Dumble ODS amps only and not stray too far into other designs as this might become too confusing.put another way what sounds good in say a Marshall style might not work as well as in a Dumble design clean and Overdrive amp

Tony

[martin manning]

Read the data sheets, and select caps based on the dielectric. I would expect that since silver mica caps are very stable with respect to temperature, voltage, frequency, and time, they would be similar in sound to C0G ceramics, which are probably rendering SM caps more and more obsolete. A direct comparison of those two would be another interesting experiment.

[10thTx]

Well, I already replaced 5 of 7 silver mica caps with the TDK COG ceramics in my Carolina Overdrive Special 5879 plus (which would be my most Dumblish influenced amp). I have one more silver mica that I will replace sometime soon (200k/500p into V1-7).

I want to spend more time with the amp using my other Tele with strat pickups and my 335ish semi-hollow body, but my initial impression is that the overdrive treble is indeed smoother without a loss in the treble tone. Best word picture I can describe would be like a child's toy spinning top that is spinning smoothly vs. spinning wobbly. There seem to be some high end artifacts that are removed using these COG ceramics.

I am not sure that clean channel alone sounds that much different? Maybe it takes the extra gain stages to fully bring out the difference?

Having said that, Tony makes a valid point in that the comparison should be done with Dumble circuits to have more validity. The experiment in my amp may negate the usefulness of this, but I'll offer for consideration for others that may want to experiment. Again, in previous amps, I found sometimes silver mica to sound better and sometimes ceramic to sound better depending on the placement.

BTW, I am super happy with how the amps sounds. While the James tone stack in the OD is an odd idea, it works quite well for me.

With respect, 10thtx

The SCH file has the B+ rail on it.

[norburybrook]

I'll jump in here and say you really need to record a before and after when doing this as it's really, really easy to convince yourself it sounds better , it's called confirmation bias and is a very real thing. I'm sure we've all had days when the amp sounds better thank others, I know I have, so it makes it very hard to make quantifiable , objective decisions on subtle component changes at times.

I've convinced myself a change of component has resulted in an improvement and then listened back to recordings only to find i was just wanting that to be true and i can't actually tell any difference.

I will continue this with a new thread about this whole thing over the next day or so. It will also mean we're not taking the OP's thread over

M

[martin manning]

Phil needs to snip this thread off starting mid-way through page 2 and create a new one. Phil?

[10thTx]

you really need to record a before and after when doing this as it's really, really easy to convince yourself it sounds better , it's called confirmation bias and is a very real thing. I'm sure we've all had days when the amp sounds better thank others, I know I have, so it makes it very hard to make quantifiable

I think that is a valid point. However, I find my recording program tends to color the tone of the amp somewhat so for me it may complicate things as much as help determine a difference. I would guess that if my recording program was really a good one, that this would be an ideal approach to A/B it.

I've played this amp with such familiarity so long, that while an "initial" change may sound favorable ………… I find that IF I play all my electrics thru a newly tweaked amp over a week or two, I'm confident that I can make a reasonably objective decision about whether there is an improvement.

Just my two cents worth. With respect, 10thtx

[talbany]

I'll jump in here and say you really need to record a before and after when doing this as it's really, really easy to convince yourself it sounds better , it's called confirmation bias and is a very real thing. I'm sure we've all had days when the amp sounds better thank others, I know I have, so it makes it very hard to make quantifiable , objective decisions on subtle component changes at times.

I've convinced myself a change of component has resulted in an improvement and then listened back to recordings only to find i was just wanting that to be true and i can't actually tell any difference.

I will continue this with a new thread about this whole thing over the next day or so. It will also mean we're not taking the OP's thread over

M

Although Marcus makes a good point here however I will just add that for me the SM to ceramic (XF5's) was pretty much in your face for me and rather an obvious change especially in Overdrive. Just sayin!
I would however like to hear the comparison between the SM and TDK COG's
BTW. IMO My 52 reissue Tele loves the ceramics.
Damn Jeff just beat me to it It's basically an HRM you have.Close enough.

Again, in previous amps, I found sometimes silver mica to sound better and sometimes ceramic to sound better depending on the placement.

I agree My SSS sounds great with Silver Micas!

Tony

[pompeiisneaks]

Phil needs to snip this thread off starting mid-way through page 2 and create a new one. Phil?

Done, hope I picked a good spot for it, it was the point where the discussion turned to ceramic caps.

Let me know if it wasn't the best place.

~Phil

[martin manning]

Thanks Phil, looks good. There is this one post, https://ampgarage.com/forum/viewtopic.p ... 47#p398947 , responding to an earlier one, that belongs in the original thread.

[pompeiisneaks]

Thanks Phil, looks good. There is this one post, https://ampgarage.com/forum/viewtopic.p ... 47#p398947 , responding to an earlier one, that belongs in the original thread.

Done.

~Phil