#102 Started. Checking in

[CHIP]

Since I've been using my D'lator as a Master Volume, I find no need for a Bright cap on my Master Vol., since I'm basically opening up the Master vol. I took them off on both of my D type amps. Both amps sound great so I guess I don't need them.

[amplifiednation]

I guess this is mostly a recap. What an awesome amp!! This really is a treat to play. The tone controls are very interactive and I think my PAB relay got fried, so I will continue to work on this...but it sounds awesome!! I am going to pull the FET as well and put a bigger dropping resistor in for B5

Not sure if everyone that helped me with the build saw my D-lator thread. I built one inside a 16x8x2 chassis and it came to life very easily. I used a Fender Reverb transformer, choke, and just did a series loop, I have parallel loop options on other gear and tend not to use them that way.

I just did this demo with some verb in the d-lator loop with my new Anderson T that just arrived today. What a smoking guitar!!! Noiseless pickups rule.

the MP3 is huge...sorry. 6MB!! both tracks with some Fuchs reverb in the loop into a sm57.

The D-lator really smoothed out the amp!! Wow, what a difference. Its really cool being able to limit the volume with the send/receive!

Also...dropped a Philips 12at7 in the PI. Calmed the OD down a bit, it needed it!!!

Very cool.

[ChrisM]

Looks good!
Why are you jumpering the top of the bright switch though?

[amplifiednation]

Looks good!
Why are you jumpering the top of the bright switch though?

Good question. Is that why my bright switches don't work properly?

I was thinking the circuit would be open without those jumpered...mistake???

[ChrisM]

Remove them and they will work.

When the bright cap is not active your jumpering pins 2/3. Cut that little piece of wire.

I am very curious to hear what you find out.

[amplifiednation]

Remove them and they will work.

When the bright cap is not active your jumpering pins 2/3. Cut that little piece of wire.

I am very curious to hear what you find out.

Ha, yup, that did it. I was wondering why they weren't working. i took out the jumpers and both switches now work!! Thanks Chris!!

[M Fowler]

Just to clarify here, that alternate bright switch pdf wiring is correct, I have used that in many amps.

Mark

[ChrisM]

Just to clarify here, that alternate bright switch pdf wiring is correct, I have used that in many amps.

Mark

But if you only use one bright cap you just omit the second cap and leave the terminal open (ie. don't jumper).

[M Fowler]

But if you only use one bright cap you just omit the second cap and leave the terminal open (ie. don't jumper).

Chris,

10-4 and I keep a variety of different types of mini switches on hand for single bright cap switching.

Mark

[amplifiednation]

I have had this NOS Sylvania yellow in my #102 V2, it was sounding really really nice, I thought I had finally found the perfect tube for that position.

This evening I opened up the amp to see where the voltages were, since when I first tubed the amp they had jumped around so much. I was only getting around 120v on V2!!

I tried a couple other NOS tubes, and V2 got right up to 205v. I tried the Sylvania in V1 and it measured even lower, at 115v!

I put a JAN GE in V2 and an RCA in V1

now I'm at normal voltages. I'm curious to hear the difference

RCA V1: 177/183
JAN GE V2: 197/205
Mullard V3: 296/296

I tested the Sylvania tube and it tests very strong. I am about to go on an internet manhunt for this information... Why the 80v swing???

[bcook]

I tested the Sylvania tube and it tests very strong. I am about to go on an internet manhunt for this information... Why the 80v swing???

I think the Sylvania's are among the best sounding tubes I've found, but I've gone through a 1/2 dozen of them. I don't know if there's some defect in manufacture or what, but they've all gone badly microphonic after a few trips to a gig. I never did bother to check the voltages-just yanked them hot, but now I'm curious. If I can find them, I'll measure them.

[bcook]

I measured 3 of them, and they all measure fine in circuit, but they may not be the "bad" ones. I can mail you one if you like.

[Structo]

Could someone clarify here. My understanding is that the master bright cap restores lost high frequencies lost through the Dumbleator.....so why do we want to attenuate the highs still further with high pf cables? What am I missing?

It is my understanding that most bright caps on volume controls act as a treble bleed so that when playing at lower levels it adds a bit more highs so it sounds good.

As you turn up, the cap has less and less effect.
Fine tuning the value is an individual, to taste type thing.

It also depends where you leave the volume set.
If you never turn up past half way then a lower value such as a 47pf or 30pf might be better.

On the Dumble amps with the added Dumbleator loop, most of us turn the master volume up to at least 12:00 and control the actual volume of the amp with the ouput pot on the D'lator.

For example, on my 100w ODS clone I turn the master volume to about 2:00 and I use a 30pf bright cap on it.
Not even sure if I hear it at that level but it's there.

[amplifiednation]

I pulled the 68pf cap off the master on Tuesday and also changed the bright switch to 220pf, and the amp still seems bright without the Dumbleator. I was hoping to be able to use some of the bright switching to help tone shape my sound, but I'm still finding that the amp sounds best without them engaged. With the Dumbleator the highs are more balanced.

[Structo]

I should preface any of my tweaks by saying I play through a large Vox 2x12 with two EVM 12L Classics.

I use a 120pf silver mica on the pre-volume bright.

I have it set up where it comes on in clean mode and turns off on OD.