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Old 3rd July 2011, 04:14 PM   #3061
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Default :)

Why do you use dual supplies if you can`t get rid of the input and output capacitors anyway?

With the single supply the capacitors will be biased by the voltage present at the the input and output, this is an advantage according to some people.

Please correct me if I am wrong.
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Old 3rd July 2011, 04:47 PM   #3062
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by Peter M. View Post
Why do you use dual supplies if you can`t get rid of the input and output capacitors anyway?
my power amps are mono amps
and I will use a 4-pole input selector

have had several of these C-core trafos for years
and I would like to use them
power supply does get bigger
and it ain't cheaper either

but I like the simpler connections to buffer/LDR curcuit
and maybe consider that its 'almost' like a 4-box preamp
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Old 3rd July 2011, 05:59 PM   #3063
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Quote:
Originally Posted by tinitus View Post
my power amps are mono amps
and I will use a 4-pole input selector

have had several of these C-core trafos for years
and I would like to use them
power supply does get bigger
and it ain't cheaper either

but I like the simpler connections to buffer/LDR curcuit
and maybe consider that its 'almost' like a 4-box preamp
Ok, then I understand
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Old 3rd July 2011, 08:51 PM   #3064
tinitus is offline tinitus  Europe
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ok
tho trying not to complicate it, I'm now thinking if there could be another pair of jfets
driving optional output
through a simple attenuator, back panel mounted

he, might be best to make it work first
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Old 4th July 2011, 10:03 PM   #3065
Itsmee is offline Itsmee  England
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Quote:
Originally Posted by tinitus View Post
ok
tho trying not to complicate it, I'm now thinking if there could be another pair of jfets
driving optional output
through a simple attenuator, back panel mounted

he, might be best to make it work first
Why not duplicate the circuit you have and wire it in parallel.
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Old 4th July 2011, 11:07 PM   #3066
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by Itsmee View Post
Why not duplicate the circuit you have and wire it in parallel.
yeah, I thought about it

but that exsta output may be only slightly attenuated
not a favourite of LDR's

I don't know yet how it will be used
woofers, subs, or maybe a tweeter

would it be better to take signal from LDR, instead of after first buffer ?
or maybe that's what you are saying ?
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Old 5th July 2011, 09:00 AM   #3067
AndrewT is offline AndrewT  Scotland
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I think your revised tapping point is better.
This way you have 2 buffers, one fixed voltage and one adjustable.
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Old 5th July 2011, 10:53 PM   #3068
tinitus is offline tinitus  Europe
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great
time to get on with it

btw, managed to cut and file down the alu blocks I need for cooling the regs
and some important allignment and smoothing work on the box too

and I have found prototype boards with 3hole pads, nice
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Old 13th July 2011, 12:22 AM   #3069
rayw is offline rayw  United States
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Hi, sorry if this has been covered but I haven't managed to make it through the whole thread yet and I'm impatient.

I'm working on a stock B1 and I'd like to go with 3 inputs, one of which is a 3.5mm jack on the front panel for an ipod, laptop, or whatever. This would mean combining the signal grounds for left and right at the jack. Will the B1 tolerate that or will I let the magic smoke out?

Thanks,
Ray
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Old 13th July 2011, 04:19 AM   #3070
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by rayw View Post
........one of which is a 3.5mm jack on the front panel for an ipod, laptop, or whatever.
This would mean combining the signal grounds for left and right at the jack. Will the B1 tolerate that or will I let the magic smoke out?

Thanks,
Ray
hey, Ray
I guess its stereo, so your jack plug would have left and right signal
you may notice a black plastic ring on the plug pin, which seperates left and right channel
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