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

[talbany]

LOl, it's what the tone control on your guitar is for

Here is the problem I had with rolling back the tone control (actually there are several) 1st is the cap in most guitars are too large and you end up rolling off to much top end. (Like throwing a blanket over your treble frequencies )
If you listen carefully to all the later generation (OD trigger) amps the top end is clear and somewhat percussive, some refer this as the ODS chirp. (yes it has a name!) it's a big part of the ODS tone. Much of this has to do with Dumbles use of the metal films on the plates,however, the combination of metal films and the SM is simply too bright in OD for a Strat. What better way to cure that than with a cheap ceramic.
2nd..You may be able to fudge around with your tone control in the studio and find a sweet spot but when I play live I really don't want to have to reach for my tone knob every time I hit my OD button A great sounding amp should be set and forget!

A well built Non HRM should be well balanced and transparent when switching between both clean and OD.(OD side just having more of the same) Both channels should sound good with no harshness anywhere and work with any guitar on any pickup setting on either rock/Jazz or mid boost or deep on.

BTW. A large part of the sound of your amp travels through yes the treble cap. The guitar is considered mainly a "treble instrument" It's where we live.
So careful consideration must be taken when choosing that cap!!. Like CW says ceramics are not consistent sounding and can measure wildly out of spec. Ceramic/SM/Polystyrene caps can all sound different given the dielectric used. especially in an amp with Overdrive. If you deviate from what is on my layouts with respect to parts types you could possibly end up with an ODS that is out of balance!
Having been down this road before.

Rant over!

Tony

[norburybrook]

LOl, it's what the tone control on your guitar is for

Here is the problem I had with rolling back the tone control (actually there are several) 1st is the cap in most guitars are too large and you end up rolling off to much top end. (Like throwing a blanket over your treble frequencies )
If you listen carefully to all the later generation (OD trigger) amps the top end is clear and somewhat percussive, some refer this as the ODS chirp. (yes it has a name!) it's a big part of the ODS tone. Much of this has to do with Dumbles use of the metal films on the plates,however, the combination of metal films and the SM is simply too bright in OD for a Strat. What better way to cure that than with a cheap ceramic.
2nd..You may be able to fudge around with your tone control in the studio and find a sweet spot but when I play live I really don't want to have to reach for my tone knob every time I hit my OD button A great sounding amp should be set and forget!

A well built Non HRM should be well balanced and transparent when switching between both clean and OD.(OD side just having more of the same) Both channels should sound good with no harshness anywhere and work with any guitar on any pickup setting on either rock/Jazz or mid boost or deep on.

BTW. A large part of the sound of your amp travels through yes the treble cap. The guitar is considered mainly a "treble instrument" It's where we live.
So careful consideration must be taken when choosing that cap!!. Ceramic/SM/Polystyrene caps can all sound different given the dielectric used. especially in an amp with Overdrive. If you deviate from what is on my layouts with respect to parts types you could possibly end up with an ODS that is out of balance!
Having been down this road before.

Rant over!

Tony

Tony,

I think if you play an ODS then you just have to accept that the balance between clean and OD is a always a compromise somewhere. I've gotten used to rolling back the tone control when I hit OD . Different guitars with different pots/Pickups react differently too to the volume roll off so that's also thrown into the equation.

With a Strat I always wire the 2nd tone into the bridge pickup only, and you can set that and forget it, the tone on the front pickup I find works fine from clean to OD on my ODS amps without any messing.

With a Tele if i'm hitting the bridge pickup I always roll back the tone live or studio, it's just something that's become second nature.

Is it really that hard to roll back your tone knob on OD? Vine Gill always rolls his tone knob as do a lot of player I know. I do know some guy's who keep everything at 100% so it's horses for courses, but I've found the tone knob combined with the volume knob/pedal an invaluable way of getting the best out of most amps for my style of playing.

thinking about it none of my amps have harsh overdive anyway so perhaps I'm speaking from a different perspective I've been in the studio today recording and using a telecaster bridge pickup with the 70's second gen ODS and I had the tone full up with a 500k pot!! nice OD sound.

YMMV

IMG_20190606_164228-01.jpeg

M

[talbany]

thinking about it none of my amps have harsh overdive anyway so perhaps I'm speaking from a different perspective

Marcus
Didn't Larry say this about the Bluesmaster?
.

He did say it sounded a bit sterile to him compared to the cream amp. I wonder if it was the HRM thing,

Are you runnin ceramics in that amp?.
Just checkin

Tony

[norburybrook]

I'm not sure what's in it without opening it. A friend of mine however who's a great guitarist thinks the Bluesmaster is THE best amp he's ever played/heard so go figure. A person's tone is indeed a very subjective thing so it makes conversations quite difficult. I personally didn't think the overdrive was harsh at all , but 'sterile' could be taken quite a few ways when describing an amp, my first thought was 'stiffness' perhaps? who know's? that BM amp has more of a 'Talk to your daughter' tone to me than the cream #102

You have got me thinking now so I'll pull it apart this weekend and have a look. I have changed the valves since Larry tried it, that's maybe another thing

I've got to put an order in for my Princeton build so I can add in some ceramics if needs be.

edit:

@Tony, I've just revisited my build thread so i can see what's in there One thing; when you say your guitar sound passes through the 'treble cap' what do you mean by this, the treble cap is a 6PS on a #102 isn't it? or are you counting the cap across the 220k on V1 pin 2? that's the only Ceramic I can see permanently in the chain not on a master.

anyway, I have a SM in there and a SM on the master volume, so I will order and replace with ceramic. It will be interesting to hear the difference it's a simple swap if i don't like it

My build thread covers all this SM/ceramic discussion too , I'd forgotten about it. I can also see looking at my BM folder the Ceriatone layout has a 33pf on the OD level control and 68pf on the clean master. I wonder if I put those on my first build, the amp Joey Landreth used.





M

[erwin_ve]

The treble cap is a 6ps and its lead is going to the cap that is located on the mid boost switch. That cap is either a silver mica(like #102) or a ceramic.
I disliked a sm on my hrm build, there is a xf5 ceramic in now after trying some other horrible sounding ceramics. Weird overtones is the best description of other than x5f ceramics.
On the 2nd Gen I love the silver mica( the big yellow ones like Charlie said earlier in this thread).

[norburybrook]

The treble cap is a 6ps and its lead is going to the cap that is located on the mid boost switch. That cap is either a silver mica(like #102) or a ceramic.
I disliked a sm on my hrm build, there is a xf5 ceramic in now after trying some other horrible sounding ceramics. Weird overtones is the best description of other than x5f ceramics.
On the 2nd Gen I love the silver mica( the big yellow ones like Charlie said earlier in this thread).

thanks Eerwin. where do you get XF5 ceramics from? Tube town don't stock them. I've got a ceramic in there, how can I tell what it is?

Mouser have a £50 minimum order so a 10c part isn't going to cut it



M

[erwin_ve]

Which value do you need? I have some in stock.
Usually they are marked
See pics of 2 different ceramics:

[norburybrook]

Erwin,

a 47 and 68 pf for a choice on the master and a 470pf for the V1 pin 2 if thats one that matters and a 390pf for the mid switch. Might as well do them all if they make a nice difference.



M

[Colossal]

Erwin,

a 47 and 68 pf for a choice on the master
M

Hi Marcus,

Any commentary on that? Different caps for different guitars?

Best,
Dave

[martin manning]

The difference in those ceramic cap specs is mostly about temperature coefficient for capacitance. The most stable are NP0/C0G, followed by X7R.

[talbany]

Erwin,

a 47 and 68 pf for a choice on the master and a 470pf for the V1 pin 2 if thats one that matters and a 390pf for the mid switch. Might as well do them all if they make a nice difference.



M

The ones that have the most impact are Clean tone stack then HRM.. then master vol (if you have one) and bright cap.. then V1B 220k bypass last. is what I hear.

BTW. Yes SM caps can make an amp sound sterile/anemic/strident/HiFi/to bright/harsh and at it's worse ice pick, are generally the cork-sniffer terms used to describe them.

Tony

[Tony Bones]

The difference in those ceramic cap specs is mostly about temperature coefficient for capacitance. The most stable are NP0/C0G, followed by X7R.

I'll add that NP0/C0G are usually constructed differently from other ceramic caps. It's a different ceramic to begin with, but possibly more importantly they are often (but not always) made from a single layer rather than the multilayer construction of X7R and lesser ceramic caps. Bottom line, they're closer to ideal than most caps. Really, their behavior is quite a bit different from other ceramics.

Do they sound better/worse/different? I don't know. I've been using TDK FG caps for a while and have been happy. They're multilayer, not single layer. It'll take someone with better ears and more experience to compare them to other types.

[talbany]

So for those interested here are some of the different type ceramics Dumble used. The OD XF5's are used mostly in the earlier 4th and 5th generation amps from the 80's.These are fairly smooth sounding ceramics (as far as ceramics go ) Later he used just plain garden variety 1KV cheap china ceramics in the later HRM's and Bluesmasters. Like Erwin mentions these can put some hair on the top end and are a good choice if your looking for an amp with a more aggressive sound which the Bluesmaster's are known for. Eventually, these ceramics will smooth out a little over years of use. Here are the pics

XF5's

20151112_125336.jpg

Bluesmaster

DumbleBMODtrim1 - Copy.jpg

DumbleBMPI2.jpg

DumbleBMStack.jpg

HRM

DumbleHRMpots.jpg

Tony

[norburybrook]

thanks for the pics Tony, Good to see even HAD can burn insulation on wires with his iron

so THIS cap on the HRM board should be a ceramic then?

HRM.png

I have a SM in there on both of my BM amp builds, I shall replace it on mine.


M

[norburybrook]

Erwin,

a 47 and 68 pf for a choice on the master
M

Hi Marcus,

Any commentary on that? Different caps for different guitars?

Best,
Dave

Dave,

No I'll try and see which one sounds best. The Ceriatone uses 68pf on the Master volume and also has a 33pf on the OD master. The layout tony did just has the 47 pf on the master.

I'll see which I like, I doubt I'll put on on the OD master.


M