Soft Start for Sonic Impact

Puffin · 10th April 2006, 02:06 PM

I have been looking at the "which toggle to use for Charlize soft start". I would like to incorporate a soft start into my S.I amp. The red switch leads are not polarised + & -. I assume therefore that it does not matter how they are connected to the switch. If I got an OFF, ON, ON switch would that be o.k and what is the best way to connect a resistor to get a soft start ? I assume the switch will have 3 terminals and (and as a novice at all this) would I be right in thinking that the resistor gets attached to one of the red leads only, or is it connected between the OFF and first ON position. Any help you can give would be greatly appreciated.

Puffin · 10th April 2006, 02:13 PM

Sorry, I forgot to say that it seems that it might be difficult to get hold of an OFF,ON,ON switch. I can get an ON, ON switch, would that do and so the same question applies as before, where do the connections go. Thanks.

weng · 10th April 2006, 03:04 PM

dunno if a soft start (resistor type) will work with the sonic impact amp.

with the charlize, you can use a simple OFF-ON switch (spst) and put a resistor across. in OFF position the amp will be fed by the psu via the resistor (+/- 4v going to the amp) and when you flip the switch to ON it will by-pass the resistor feeding the amp direct from the psu at 12v. you need another switch though to cut the psu as it will feed the amp even in OFF position. in my case i have another switch that directly cuts the 220v going to the psu.

Puffin · 11th April 2006, 12:13 PM

Have any other of you electronic wizards got any suggestions ?

cpemma · 11th April 2006, 02:04 PM

OFF-ON-ON may seem the "best" way but certainly with a submin toggle I find ON-OFF-ON is easier to manipulate and the switches are more common. With a plain SPDT (ON-ON) (or any manual soft-start, come to that) I'm not sure what effect leaving the amp on a strangled supply would have.

The resistor goes across the two 'ON' pins, a red lead to one of them, the other red to the common pin. Which pin depends on whether your convention is 'up for on' or 'down for on'.

Main value with the T-Amp will be to gently pre-charge the big stiffener cap you've added should your psu object.

Puffin · 11th April 2006, 02:28 PM

cpemma. Thanks for that. The way you have described the wiring up, is that for an ON-OFF-ON switch ? I seem to remember that panomaniac suggested this for the charlize. It means a quick up(or down) from the first ON position to FULL on (2nd on position) passing the OFF position.
I think ?

BWRX · 11th April 2006, 03:21 PM

Thumpless turn-on mod for Tripath amps

I posted my soft start circuit a little while back and Michael showed us the one the Super-T amp uses. You can make either circuit on perf board for a few dollars in parts. You just need to give it power, ground, and run the soft start signal to the mute pin (after you lift or disconnect the mute pin from the circuit) and it will work every time you power up the amp.

Puffin · 11th April 2006, 03:32 PM

Thanks BWRX. However, I think it would be beyond my capabilities and a simple resistor solution as suggested by cpemma is far more to my liking. Do you have any comments on the resistor suggestion ?

weng · 11th April 2006, 04:06 PM

Quote:

Originally posted by Puffin
Thanks BWRX. However, I think it would be beyond my capabilities and a simple resistor solution as suggested by cpemma is far more to my liking. Do you have any comments on the resistor suggestion ?

u can also refer to this thread regarding the function of spdt (ON-ON) and spst (OFF-ON) to use for the resistor based soft start config.

Which toggle to use for Charlize Soft Start

cpemma · 11th April 2006, 04:35 PM

Quote:

Originally posted by Puffin
cpemma. Thanks for that. The way you have described the wiring up, is that for an ON-OFF-ON switch ? I seem to remember that panomaniac suggested this for the charlize. It means a quick up(or down) from the first ON position to FULL on (2nd on position) passing the OFF position.
I think ?

Correct, but resistor across the two 'ON' outputs with supply wire from the one chosen as 'Full ON' applies to any 3-position switch. I see RS do an SP ON-ON-ON min toggle that could be used as an OFF-ON-ON (with the first 'ON' not connected), 344-710 is the code and pin-out is on the page.

10th April 2006, 02:06 PM	#1
Puffin diyAudio Member Join Date: Feb 2006 Location: U.K	Soft Start for Sonic Impact I have been looking at the "which toggle to use for Charlize soft start". I would like to incorporate a soft start into my S.I amp. The red switch leads are not polarised + & -. I assume therefore that it does not matter how they are connected to the switch. If I got an OFF, ON, ON switch would that be o.k and what is the best way to connect a resistor to get a soft start ? I assume the switch will have 3 terminals and (and as a novice at all this) would I be right in thinking that the resistor gets attached to one of the red leads only, or is it connected between the OFF and first ON position. Any help you can give would be greatly appreciated.

10th April 2006, 03:04 PM	#3
weng diyAudio Member Join Date: Feb 2006 Location: ormoc	dunno if a soft start (resistor type) will work with the sonic impact amp. with the charlize, you can use a simple OFF-ON switch (spst) and put a resistor across. in OFF position the amp will be fed by the psu via the resistor (+/- 4v going to the amp) and when you flip the switch to ON it will by-pass the resistor feeding the amp direct from the psu at 12v. you need another switch though to cut the psu as it will feed the amp even in OFF position. in my case i have another switch that directly cuts the 220v going to the psu. __________________ noob on the block

11th April 2006, 03:21 PM	#7
BWRX diyAudio Moderator Emeritus Join Date: Jan 2005 Location: Pennsylvania	Thumpless turn-on mod for Tripath amps I posted my soft start circuit a little while back and Michael showed us the one the Super-T amp uses. You can make either circuit on perf board for a few dollars in parts. You just need to give it power, ground, and run the soft start signal to the mute pin (after you lift or disconnect the mute pin from the circuit) and it will work every time you power up the amp. __________________ Brian

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
Soft Start Necessary?	dtaylo3	Class D	2	26th December 2008 10:05 AM
B+ soft start	Gluca	Tubes / Valves	2	3rd September 2007 02:04 PM
Need a soft start?	maxpou	Solid State	19	18th April 2007 10:23 PM
bi-amping with sonic impact t amp/using sonic impact amp for headphones	jon_m	Class D	3	16th February 2006 11:16 AM
Soft start & Soft Switch circuit: can anybody help?	m.parigi	Solid State	95	22nd August 2005 04:32 PM


	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

10th April 2006, 02:13 PM	#2
Puffin diyAudio Member Join Date: Feb 2006 Location: U.K	Sorry, I forgot to say that it seems that it might be difficult to get hold of an OFF,ON,ON switch. I can get an ON, ON switch, would that do and so the same question applies as before, where do the connections go. Thanks.

11th April 2006, 12:13 PM	#4
Puffin diyAudio Member Join Date: Feb 2006 Location: U.K	Have any other of you electronic wizards got any suggestions ?

11th April 2006, 02:04 PM	#5
cpemma diyAudio Member Join Date: Jul 2003 Location: S Yorkshire OK	OFF-ON-ON may seem the "best" way but certainly with a submin toggle I find ON-OFF-ON is easier to manipulate and the switches are more common. With a plain SPDT (ON-ON) (or any manual soft-start, come to that) I'm not sure what effect leaving the amp on a strangled supply would have. The resistor goes across the two 'ON' pins, a red lead to one of them, the other red to the common pin. Which pin depends on whether your convention is 'up for on' or 'down for on'. Main value with the T-Amp will be to gently pre-charge the big stiffener cap you've added should your psu object.

11th April 2006, 02:28 PM	#6
Puffin diyAudio Member Join Date: Feb 2006 Location: U.K	cpemma. Thanks for that. The way you have described the wiring up, is that for an ON-OFF-ON switch ? I seem to remember that panomaniac suggested this for the charlize. It means a quick up(or down) from the first ON position to FULL on (2nd on position) passing the OFF position. I think ?

11th April 2006, 03:32 PM	#8
Puffin diyAudio Member Join Date: Feb 2006 Location: U.K	Thanks BWRX. However, I think it would be beyond my capabilities and a simple resistor solution as suggested by cpemma is far more to my liking. Do you have any comments on the resistor suggestion ?

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

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