TAD Super Lead 100w - My first build

Prowler · Post by **Prowler** » Sun Sep 21, 2014 6:48 am

Wow, this mod kicks ass! Thanks Danman! I can hear Van Halen, Ac/Dc and Slash tones are there but the amp still doesn't sound right.

I didn't have the right components so I used those that were quite close to the specs posted above. I can't wait for the next weekend when put in the right components!

Here are the latest pics:

http://1drv.ms/1AZj7db

The blue caps are 560pf ceramic.

It is time to think about the case I am going to put the amp into. I think something like this with more rounded edges and a Marshall face plate would look cool:

http://www.bluetone.fi/wp-content/uploa ... 24x575.jpg

Or then I just put it in a case that is just some sanded wood.

http://www.trmguitarcabs.com/Marshall_head_cab_006.JPG

https://reverb-res.cloudinary.com/image ... d8mpnp.jpg

http://lumberjocks.com/assets/pictures/ ... 3-438x.jpg

danman · Post by **danman** » Sun Sep 21, 2014 9:45 am

I'm glad you like it! It really has been the best version that I have tried so far.

Prowler · Post by **Prowler** » Sun Sep 21, 2014 9:50 am

danman wrote:I'm glad you like it! It really has been the best version that I have tried so far.

No squealing this time or any extra noises. I was impressed how dynamic the amp became. This mod is a must for everyone looking for that high-gain plexi tone.

Prowler · Post by **Prowler** » Wed Sep 24, 2014 12:34 pm

Today I installed some of the components for this one-wire mod but I made a mistake when ordering the components and some of them are wrong value.

I think the amp sounds better now when I connect to the impedance selector's 4 ohm tap. Previously I had connected to the 16 ohm's tap.

Where do I connect the 100k resistor? Between the purple wire and the 4 ohm's tap? How does this resistor affect the sound?

Thanks for all the help guys! The amp sounds better and better everytime when I mod it.

danman · Post by **danman** » Wed Sep 24, 2014 4:57 pm

Are you asking about the NFB resistor on the turret board that connects to the impedance selector?

danman · Post by **danman** » Wed Sep 24, 2014 5:05 pm

There shouldn't be any other resistor that connects between the purple wire and the selector. The NFB resistor will be mounted to the turret board. You can adjust the value of this resistor and which tap you use to vary the NFB. More NFB will make the amp tighter (move to a higher tap or lower the resistor value) and less NFB will make the amp looser and gainier (lower tap or higher resistor value). I usually connect the purple wire to the 8ohm tap and then just adjust resistor values to my liking.

Did you ever try the mod I mentioned where you place a .0047uf cap between the purple wire end and the impedance tap? It's a fixed resonance mod and it will tightened up your bass quite a bit.

Prowler · Post by **Prowler** » Wed Sep 24, 2014 8:42 pm

danman wrote:There shouldn't be any other resistor that connects between the purple wire and the selector. The NFB resistor will be mounted to the turret board. You can adjust the value of this resistor and which tap you use to vary the NFB. More NFB will make the amp tighter (move to a higher tap or lower the resistor value) and less NFB will make the amp looser and gainier (lower tap or higher resistor value). I usually connect the purple wire to the 8ohm tap and then just adjust resistor values to my liking.

Did you ever try the mod I mentioned where you place a .0047uf cap between the purple wire end and the impedance tap? It's a fixed resonance mod and it will tightened up your bass quite a bit.

I haven't tried the 0.0047 cap yet. I think I will try the 8 ohm tap next time without the 0.0047 cap and then with the cap.
Can I try 100k as the NFB resistor?

Prowler · Post by **Prowler** » Thu Sep 25, 2014 12:52 pm

I tried 0.0047 cap to the 8 ohm tap and then to the 4 ohm tap. I ended up connecting to the 4 ohm tap without the cap.
I also tried 100k to the NFB resistor but I didn't like it. Maybe i should try something like 33k to the NFB resistor and see what happens.

danman · Post by **danman** » Thu Sep 25, 2014 5:10 pm

I have used anywhere from 27k up to 100k for the NFB resistor. Try several values to see what you like. The lower the value the tighter the amp will sound and the higher values will make the amp sound hairier.

Prowler · Post by **Prowler** » Fri Sep 26, 2014 9:56 am

Next Sunday it is time for swapping the preamp tubes. I am not quite happy how the amp sounds with this set that I am running now:

V1 Tung-sol 12AX7
V2 JJ ECC83s
V3 JJ ECC83s

The power tubes are EL34B-STR TAD-Tubes, Premium Matched Pair (biased at 35mV)

I also have these preamp tubes:

1x JJ ECC803S
2x JAN GE 5751
1x 12AY7 (ehx)
3x ECC83 WA TAD Premium Selected

2x JJ EL34 Power Tubes

Which combination of these preamp tubes should sound good? I think I am going to try JAN GE 5751 to the V1 first.
Maybe I will record some clips if I am not too busy swapping the tubes.

Opinions please!

neikeel · Post by **neikeel** » Fri Sep 26, 2014 10:12 am

5751 is slightly lower gain than the others (but more than an ECC81/12AT7 and lot more than an ECC82, sounds good in a SL V3 or can be good in V1 if you are cascading. The other tubes are not ones I would normally use but would be interested in knowing what you find!
The 12AY7 will be pretty low gain (more than an ECC82 but less than a 12AT7/ECC81)

GilmourD · Post by **GilmourD** » Sun Sep 28, 2014 12:02 pm

Try the JJ ECC803S in V1 with the TADs in V2 and V3.

Prowler · Post by **Prowler** » Sat Oct 04, 2014 1:18 pm

danman wrote:I have used anywhere from 27k up to 100k for the NFB resistor. Try several values to see what you like. The lower the value the tighter the amp will sound and the higher values will make the amp sound hairier.

33k NFB resistor connected to the 4 ohm's tap seems to work well with this amp. Maybe I will try 27k tomorrow. Carbon composition resistor seemed to sound the best compared to a carbon film resistor with the same value.

Is a 0.5W carbon composition resistor safe to install as NFB resistor?

neikeel · Post by **neikeel** » Sun Oct 05, 2014 9:33 am

Prowler wrote:
danman wrote:I have used anywhere from 27k up to 100k for the NFB resistor. Try several values to see what you like. The lower the value the tighter the amp will sound and the higher values will make the amp sound hairier.
33k NFB resistor connected to the 4 ohm's tap seems to work well with this amp. Maybe I will try 27k tomorrow. Carbon composition resistor seemed to sound the best compared to a carbon film resistor with the same value.

Is a 0.5W carbon composition resistor safe to install as NFB resistor?

Yes

Prowler · Post by **Prowler** » Wed Oct 15, 2014 1:17 am

I think I will start doing the Slash mod tomorrow:

https://onedrive.live.com/?cid=330949d4 ... UuAUk4AjWI

I tried many kinds of caps and resistors but was not happy how the amp sounded with the one-wire mod.

I guess I will dig up my dim-bulb tester from somewhere and check the voltages and do the biasing again. Or is this all necessary?

Is there a voltage chart somewhere for this mod?

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TAD Super Lead 100w - My first build

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Re: TAD Super Lead 100w - My first build

Re: TAD Super Lead 100w - My first build

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Re: TAD Super Lead 100w - My first build

Re: TAD Super Lead 100w - My first build

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