Tube boost + overdrive running off a 9 volt battery

[Jdansti]

I finished my Valve Overdrive 9V with some mods (tone & clipping switchable) with a very nice sounding fuzz.
It sounds great !

Nice looking build!

[Isak]

Rene,

i'm a bit confused about your layout..
what i have is the one with c3 NP cap and in the gallery you put a layout with c3 as polarized cap.
i didnt made the layout yet cause i'm waiting for some parts to arrive.
can you please advise me?

Q ..
i'm a bit confused about the wall wart that i'll be using, i see all kind of wall warts in this post.
my plan is to use an regulated 12V wall wart, as i understand it will work fine with it, but i see on page 144 that Mustachio talked about multiply the V, for what reason if i may ask?
will it be a better results with more V?

Q ..
in here http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html
there is B+V inserts?
i dont understand...
you wrote..
"12V goes only to pin 5 - B is whatever voltage you want to apply to the plates."
what is B?
as i understand B can be any V i want to use?
to what pin B is connected?
do i take B from the same wall wart?

sorry for the lots of questions, i'm trying to understand and to learn.

thank you very much,
Sincerely,
Isak E.

[texstrat]

Rene,

i'm a bit confused about your layout..
what i have is the one with c3 NP cap and in the gallery you put a layout with c3 as polarized cap.
i didnt made the layout yet cause i'm waiting for some parts to arrive.
can you please advise me?

Q ..
i'm a bit confused about the wall wart that i'll be using, i see all kind of wall warts in this post.
my plan is to use an regulated 12V wall wart, as i understand it will work fine with it, but i see on page 144 that Mustachio talked about multiply the V, for what reason if i may ask?
will it be a better results with more V?

Q ..
in here http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html
there is B+V inserts?
i dont understand...
you wrote..
"12V goes only to pin 5 - B is whatever voltage you want to apply to the plates."
what is B?
as i understand B can be any V i want to use?
to what pin B is connected?
do i take B from the same wall wart?

sorry for the lots of questions, i'm trying to understand and to learn.

thank you very much,
Sincerely,
Isak E.

Isak:

If you want to simplify your build, use this schematic and values. Disregard my drawing regarding the voltage regulator on the DC jack.


The resistor value to the LED is 4.7K. C3 is a electrolytic cap with positive going to Pin 6.

Make your 12v wall wart is putting out 12v at the plug and that the plug orientation is pin (negative), sleeve (positive). 

B is the supply voltage. You do not want to exceed 12.6V to the heaters; otherwise, you run the risk of burning them out or shortening their service life.

The values I have listed on the schematic I derived from reading all 145 pages and found that they were the best for me and to use with a single coil or humbucker guitar.

I did put a ON-ON switch at C1 and used two different NP caps for a lighter/darker sound depending on the guitar.

Hope this helps and good luck.

[rutabaga bob]

@Isak:  the 'B' referred to is the voltage applied to the plates.  In the standard build, the 12 volt supply is used both for the heater and the plate voltage.  With a voltage multiplier, the 12 volts goes to the heater only, and the multiplied (higher) voltage goes to the plates.    Larry

[Renegadrian]

@ Isak E.
C3 can be either NP or polarized...I tend to use the latter as its smaller size...
You can go straight with 12 V serving the whole ckt - adding more V to the plates will give you more "air", dynamics, headroom or whatever way you wanna call it!!! XD
If you want to use a voltage multiplier, be sure to provide 12V to the heaters and the increased voltages to the plates, which are pins 1 and 6. Voltage is meant to be any kind you want, basically the tube can get up to 330 V but without going that high and using a trafo you can use a simple multiplier to get from 48 V to 200 V.

[Isak]

thank you for the info.
i'v never worked with Tubes so still learning here

thanks again,
Isak E.

[mwynwood]

Hi Patrick,
Just wondering - what's the Switch (0.056uF Cap, 22k resistor) coming from Pin 8 going to the output tip do?

[Ark Angel HFB]

I feel a little dizzy but after an hour of thinking this over here is what I'm at.

As far as powering this thing is concerned I can ether go with a 12vDC then boost that... http://www.mpja.com/12VDC-1A-Plug-Supply-55_21mm-Plug/productinfo/19087+PS/

just go with a 15vDC regulate down for heaters... and boost the 15vDC for more head room... http://www.mpja.com/15V-16A-DELTA-PLUG-POWER-SUPPLY/productinfo/16714+PS/

the advantage of the 15vDC is that by regulating down the power is well... regulated meaning the power will be both regulated and filtered.

so...

Q1: Are the two wall warts I linked two seem good to you more experiences dudes?

Q2: Which one, if it was your money, would you personally go with?

[tasos]

None actually...
Switching power supplies are not the best thing to use with pedals....

I am powering my valvecaster with 9volt and it sounds cool!
High output and a lot of grit.

[DUCKFACE]

1. may C3 be non pole capacitor like 1mf wima red block?
2 .how does it handle on 12V ?
3. is it good for preamp ?

[Renegadrian]

1. may C3 be non pole capacitor like 1mf wima red block?

Yes, As I wrote it can be NP or electro...while I prefer electro (for its smaller dimentions) a NP cap can be used. WIMAs are a good choice!

2 .how does it handle on 12V ?
3. is it good for preamp ?

You mean the whole ckt?! IT IS a preamp/booster, intended to work at 12V. The very first incarnation of it (by the great Dano) works quite great, altough it is a nice base for experiments and variations.

[Ark Angel HFB]

None actually...
Switching power supplies are not the best thing to use with pedals....

I am powering my valvecaster with 9volt and it sounds cool!
High output and a lot of grit.

Forgive my lack of knowledge but why is switching power supply bad?

Also how about everyone give a modle number of the PS we are using... it might be a good thing to add as let face it none of us are made of money and find the right adaptor for the right price is a good thing. ^_^

[iccaros]

 A SMPS is not bad on its own, its when you have a SMPS plug and a SMPS inside of the pedal you can have issues of hydrodyning (http://en.wikipedia.org/wiki/Heterodyne), but with a stock valve caster I see no issues at all, as long as they have a high enough switching frequency.

I have a 12v wall wart from Radio Shack, which I believe is a SMPS and a Voltage multiplier (which is a SMPS) in my valvecaster giving me 70v on the plates. This works well and I have zero issues. Others have done the same with no issues.  If you start @ 9v with a onespot I have found also no issues. Using ricks SMPS design giving me 120v on the plates, and using a voltage regulator to get 6.3v on the heaters.

[bassmannate]

Wanting to try to build a pcb version. Does anyone know if the socket sold on smallbear is a pcb socket? It doesn't say on the page and I tried e-mailing them a while back and got no response.

[Ark Angel HFB]

Wanting to try to build a pcb version. Does anyone know if the socket sold on smallbear is a pcb socket? It doesn't say on the page and I tried e-mailing them a while back and got no response.

Just look at the lugs on the bottom of the socket... if they look like they'd be a bitch to solder... they are PBC. XD

at least that is my rule of thumb. ^_^

[chris73]

Here is mine, not so pleased with the metal work...


Thank you all and especialy Adriano

[Renegadrian]

Here is mine, not so pleased with the metal work...
http://imageshack.us/photo/my-images/717/img3458ee.jpg
http://imageshack.us/photo/my-images/33/img3457lx.jpg
Thank you all and especialy Adriano

(links fixed)

Nice! Glad if I helped you somehow!!!

[bassmannate]

Wanting to try to build a pcb version. Does anyone know if the socket sold on smallbear is a pcb socket? It doesn't say on the page and I tried e-mailing them a while back and got no response.

Just look at the lugs on the bottom of the socket... if they look like they'd be a bitch to solder... they are PBC. XD

at least that is my rule of thumb. ^_^

I'm well aware of what PCB lugs look like. Unfortunately, the item description on Small Bear doesn't say and the picture is of the top of the socket. You can't see the lugs. Is there anyone who's bought tube sockets from Small Bear before that can comment?

[Mustachio]

Well I moved it off the bread board and onto some vero I made black. I added a 7812 to the right side of the board added a single 100uf cap on the power side coming in nothing on the going out.

I have hum but here's what my thoughts are maybe you can confirm or deny. the power coming in is from a danelectro zero hum wall adapter that's rated at 18vdc 150ma. It reads out 28.6vdc and 748ma so I figured it would have enough juice to push this circuit. I ran a jumper right in front of the power coming from the wall wart to the B+ so its unregulated I'm guessing , then it hits the 100uf cap on the + and into the regulator the - of the cap goes to center ground on the regulator and the right side is the 12v regulated out.

I'm guessing I'm getting hum from the unregulated power coming into the B+ straight from the wallwart. If I move the B+ jumper(blue wire on left side of regulator) behind the 100uf cap will that help ? or should I send the wallwart power to a 7818 before it hits B+ . that way power coming into it goes left to a 7818 making 18v regulated for B+ and goes on to the 7812 for pin 5.

Also I'm planning on making the voltage multiplier to feed B+ later and Id like your advice . The IC is rated at max 18v in , so should I go with my 18v regulator or a 15v regulator the 7815 and feed the chip 15v to be on the safe side ? And am I getting into danger areas on heat if i used 2 regulators and a multiplier in the same box?

I hope this makes sense my mustachio curled up just typing about it haha.

In the pics I have a 12BH7 in there Haven't had a chance to test it with the 12au7 or 12ax7s I have. I did test it with a 12v 1amp walwart same hum then it mysteriously stopped working after 30 seconds and I plugged back in the danelectro wart Ive been using from the start and it worked again  


I built the tube cage with parts from the hardware store under 5 bucks and left over parts still to make a few more. Might go with different material next time or sand and polish these up. Or even paint! Got to use my new drill press on this box! was a lot of fun! and I hand sanded the top with some 1000 and then 2500 grit paper. Still has a lil more work to go. Used a bud industries CU-471 box . Pretty nice size.




Guts





[EDIT]
Opps I used this layout but moved the regulator down to unused space on my vero

http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html

and this is the multiplier Im planing on making just shy one cap at the moment.

http://www.aronnelson.com/gallery/main.php/v/Renegadrian/40106+voltage+multiplier.gif.html

[Jdansti]

Could someone please take a look at my calculations below and let me know if I'm on track?

I've built a Valvecaster using a 12AU7 at 12v and it works fine. I would like to substitute some 6N6P and 6N1P-EB tubes I have to see how they sound, but the heater voltage rating for these tubes is 6.3v across pins 4 & 5, and pin 9 is not connected between the heaters as it is on the 12A?7 tubes.   Otherwise, the pin out is the same. 

Based on calculations I found at http://www.diyforums.org/MAX/MAXheaterResistor.php, I think that I can place a 10 ohm resistor in series with the heater to drop the voltage close to 6v. 

The procedure: 
1) calculate the normal heater power based on the specs,  
2) calculate the heater resistance,
3) assume a 12v PS and a 10 ohm (a guess) resistor in series with the heater to calculate the resulting current, 
4) calculate the voltage drop and the voltage that the heater would see. 

Any comments would be appreciated. 

Heater Rating: 6.3v, 750mA

Heater Power
P = V x I
P = 6.3 x 0.750
P = 4.725W

Heater Resistance
R = P/I^2
R = 4.725 / 0.750^2
R = 8.4 ohms

Assume: 12.6V PS and R1 = 10ohm resistor in series with heater.

Current
I = V/(Heater R + R1)
I = 12.6/(8.4+10)
I = 685mA

Voltage Drop Across R1 (10 ohms)
V = I x R
V = 0.685 x 10
V = 6.85v

Heater Voltage
V = PSv-Vdrop
V = 12.6 - 6.85
V = 5.8v

I would need to make sure that the resistor was either rated at 1W, or use two 20 ohm 1/2W resistors in parallel. My power supply is rated at 1200mA, so it should be fine. Thanks in advance.