Fender 5C1 Choke

chrismercurio · 17th December 2010, 06:43 PM

All,

I'm putting together a Fender 5C1 clone and want some advice on the choke in the CLC supply for the B+. Simulated at 10H, ripple is ~20mV and at 5H ripple is ~40mV. I believe original Fender chokes were ~4H.

What are the advantages/disadvantages to going with the 5H over the 10H and vise versa?

Thank you,

Nigel Goodwin · 17th December 2010, 08:23 PM

I would suggest using the same as Fender did - valve amplifiers are really about low quality, improving the quality of the design will probably affect the sound in ways you don't want. Part of the 'valve sound' which some people seem to find appealing is partly down to poor power supplies, bad regulation, and excessive mains hum. This is why some modern designs have switchable rectifiers, modern silicon ones for higher and cleaner output, and original valve ones for lower power, higher distortion, and a nice 'droopy' HT rail.

chrismercurio · 17th December 2010, 08:32 PM

I want low noise. Fender did what they did as a "good enough" solution not to create "the sound". "The sound" came from timeless recordings made using what was available. So bigger choke, lower noise and less sag? (I want less sag.)

Enzo · 18th December 2010, 01:06 AM

You making a 5C1 or a 5E1?

5E1 - choke, 6V6, 12AX7, 5Y3.

5C1 - 500 ohm resistor, 6V6, 6SJ7, 5Y3.

First, this is a single ended amp - one power tube. it is running in class A, so you are not getting sag to begin with.

Are you using those tiny little 8uf filter caps as in the original? Bump those up to 20uf and see how that smooths things.

chrismercurio · 18th December 2010, 08:51 AM

5c1 variant...
clc ps
cathode bias

VictoriaGuy · 18th December 2010, 04:01 PM

Chris-
I think your amp will be 'quiet enough' when you get it built, with the design 'as is'. Pay attention to your grounding in the build.
Most guitars are so noisy (especially single coil PUs) that amp noise is a minor thing...ie amp is quiet, plug in guitar and the fun starts.
All in the game.....

John
PS- make sure you use a decent speaker (eg Weber speaker for Champ or better); the 'original' speakers that Leo used were pretty cheap. (I've owned a few tweed Champs).

Cassiel · 18th December 2010, 04:28 PM

Quote:

Originally Posted by VictoriaGuy

Chris-
ie amp is quiet, plug in guitar and the fun starts.
All in the game.....

Yeeeeeeah! Unless he plays with his avatar's guitar.

Most electric guitars are so noisy that worrying about the size of the choke sounds funny.

Quote:

I want low noise.

Quote:

I want less sag

So, why are you building this one? SE with tube rectifier.

chrismercurio · 18th December 2010, 08:38 PM

I have a 2 ch EL34 PP with SS rectifier and tone stack. I want something different, simple, and not quite as loud.

For speaker I haven't decided between the Scumnico 12", the ToneTubby 12" or the Weber NeoMag 15". I like the clean sound of the old JBL D130 a lot.

Best,

Cassiel · 18th December 2010, 09:11 PM

OK, go with the choke with less resistance (5H). Hum should be low. I like the pentode preamp but your guitar pickups need to output a strong signal, otherwise gain might not be enough. Depending on how loud you want it to be the speaker sensitivity will be very important.

chrismercurio · 19th December 2010, 12:17 AM

I figured I could alter my overall SPL output via speaker choice.

Most guitar amplifier schematics I have looked at only have volume controls as gain attenuation at the amplification stage. Are there any advantages to adding a pot at the input so that the gain at both the preamp and the power amp can be attenuated?

17th December 2010, 06:43 PM	#1
chrismercurio diyAudio Member Join Date: Aug 2006 Location: Silicon Valley	Fender 5C1 Choke All, I'm putting together a Fender 5C1 clone and want some advice on the choke in the CLC supply for the B+. Simulated at 10H, ripple is ~20mV and at 5H ripple is ~40mV. I believe original Fender chokes were ~4H. What are the advantages/disadvantages to going with the 5H over the 10H and vise versa? Thank you,

17th December 2010, 08:23 PM	#2
Nigel Goodwin diyAudio Member Join Date: Jul 2005 Location: North Derbyshire	I would suggest using the same as Fender did - valve amplifiers are really about low quality, improving the quality of the design will probably affect the sound in ways you don't want. Part of the 'valve sound' which some people seem to find appealing is partly down to poor power supplies, bad regulation, and excessive mains hum. This is why some modern designs have switchable rectifiers, modern silicon ones for higher and cleaner output, and original valve ones for lower power, higher distortion, and a nice 'droopy' HT rail. __________________ Nigel Goodwin

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Help replacing a PSU choke - How to choose choke	Hubba	Tubes / Valves	2	10th September 2010 02:33 PM
Fender Champ 5C1 help needed!	Spasticteapot	Instruments and Amps	12	27th July 2010 11:45 PM
Choke rating for choke input duty	cbutterworth	Tubes / Valves	14	9th November 2007 04:43 PM
Swinging choke vs std. choke in PS	Curly Woods	Tubes / Valves	2	5th March 2007 08:30 PM
Fender amplifier.. burnt choke ??	rainerm_au	Tubes / Valves	2	22nd February 2005 10:21 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

17th December 2010, 08:32 PM	#3
chrismercurio diyAudio Member Join Date: Aug 2006 Location: Silicon Valley	I want low noise. Fender did what they did as a "good enough" solution not to create "the sound". "The sound" came from timeless recordings made using what was available. So bigger choke, lower noise and less sag? (I want less sag.)

18th December 2010, 01:06 AM	#4
Enzo diyAudio Member Join Date: Sep 2004 Location: Lansing, Michigan	You making a 5C1 or a 5E1? 5E1 - choke, 6V6, 12AX7, 5Y3. 5C1 - 500 ohm resistor, 6V6, 6SJ7, 5Y3. First, this is a single ended amp - one power tube. it is running in class A, so you are not getting sag to begin with. Are you using those tiny little 8uf filter caps as in the original? Bump those up to 20uf and see how that smooths things.

18th December 2010, 04:01 PM	#6
VictoriaGuy diyAudio Member Join Date: Dec 2008 Location: Victoria, BC	Chris- I think your amp will be 'quiet enough' when you get it built, with the design 'as is'. Pay attention to your grounding in the build. Most guitars are so noisy (especially single coil PUs) that amp noise is a minor thing...ie amp is quiet, plug in guitar and the fun starts. All in the game..... John PS- make sure you use a decent speaker (eg Weber speaker for Champ or better); the 'original' speakers that Leo used were pretty cheap. (I've owned a few tweed Champs).

18th December 2010, 08:38 PM	#8
chrismercurio diyAudio Member Join Date: Aug 2006 Location: Silicon Valley	I have a 2 ch EL34 PP with SS rectifier and tone stack. I want something different, simple, and not quite as loud. For speaker I haven't decided between the Scumnico 12", the ToneTubby 12" or the Weber NeoMag 15". I like the clean sound of the old JBL D130 a lot. Best,

18th December 2010, 09:11 PM	#9
Cassiel diyAudio Member Join Date: Sep 2004 Location: Madrid	OK, go with the choke with less resistance (5H). Hum should be low. I like the pentode preamp but your guitar pickups need to output a strong signal, otherwise gain might not be enough. Depending on how loud you want it to be the speaker sensitivity will be very important.

19th December 2010, 12:17 AM	#10
chrismercurio diyAudio Member Join Date: Aug 2006 Location: Silicon Valley	I figured I could alter my overall SPL output via speaker choice. Most guitar amplifier schematics I have looked at only have volume controls as gain attenuation at the amplification stage. Are there any advantages to adding a pot at the input so that the gain at both the preamp and the power amp can be attenuated?

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)