Next project is a balanced control unit.
Here is the concept schematic:
Valve choice is yet to be decided upon. 6AQ5s are shown just to get the thing drawn out.
PSU will either be an active regulated or a passive with 1600uF of JJ cap bank, for high filtration. Just throwing ideas about at the moment.
Balanced Control Unit
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#1 Balanced Control Unit
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#2
Component values added:
This is the basic cct I will probably pursue.
Gain of about 6 and plenty of current driving ability.
Whether microphonics will be an issue, I won't know until I have built it.
This is something that needs breadboarding first...My God!...I've said that dreaded word!
This is the basic cct I will probably pursue.
Gain of about 6 and plenty of current driving ability.
Whether microphonics will be an issue, I won't know until I have built it.
This is something that needs breadboarding first...My God!...I've said that dreaded word!
Sgt. Baker started talkin’ with a Bullhorn in his hand.
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#3
It's not so bad Steve.SteveTheShadow wrote: This is something that needs breadboarding first...My God!...I've said that dreaded word!
Is a control unit the same as a pre-amp ?
The only thing necessary for the triumph of evil is for good men to do nothing.
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G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
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#4
Aye..just thought I'd be different and use the old terminology.pre65 wrote:
Is a control unit the same as a pre-amp ?
Sgt. Baker started talkin’ with a Bullhorn in his hand.
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#5
I should be getting a new line preamp shortly, transformer output with balanced and phono connections to power amp. More details next week.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
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#6
This preamp should give me a lot more flexibility concerning what can be connected to the system.
At the moment, I can connect only the computer via the balanced outputs of the DAC.
I want to be able to connect other things to the system.
Additionally, although there is sufficient gain from the 2 stages of amplification within the power amp, it is cutting things very fine as I am listening at 3 o'clock on the volume control. I really could do with another stage of voltage gain, which the preamp will provide.
Adding 12dB of boost in the digital domain via iTunes makes things perfect ie the amp just clips at maximum volume, but this is not the ideal situation.
So adding gain at the front is a good solution, and another 12dB is what I am looking for. Whether 6AQ5s will supply this is another question I need to deal with.
At the moment, I can connect only the computer via the balanced outputs of the DAC.
I want to be able to connect other things to the system.
Additionally, although there is sufficient gain from the 2 stages of amplification within the power amp, it is cutting things very fine as I am listening at 3 o'clock on the volume control. I really could do with another stage of voltage gain, which the preamp will provide.
Adding 12dB of boost in the digital domain via iTunes makes things perfect ie the amp just clips at maximum volume, but this is not the ideal situation.
So adding gain at the front is a good solution, and another 12dB is what I am looking for. Whether 6AQ5s will supply this is another question I need to deal with.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#7
preamp?, breadboard?, Nightmare!SteveTheShadow wrote:
This is something that needs breadboarding first...My God!...I've said that dreaded word!
There's nowhere you can be that isn't where you're meant to be
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#8
Yikes!ed wrote: preamp?, breadboard?, Nightmare!
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#9
Hi Steve,
Your balanced preamp looks like a good place to add a CCS. If you CCS loaded the pair of tubes in the preamp the preamp could accept balanced or single ended inputs and provide a balanced output.
Unless you go for a good transformer the CCS will perform better. The little Sowter 10K:10K transformers measure pretty good but have an opaque sound. The Tribute inputs are amazingly transparent as well as measure great. The CCS load sounded very much like the Tribute input transformer.
Just thinking...
Gary
Your balanced preamp looks like a good place to add a CCS. If you CCS loaded the pair of tubes in the preamp the preamp could accept balanced or single ended inputs and provide a balanced output.
Unless you go for a good transformer the CCS will perform better. The little Sowter 10K:10K transformers measure pretty good but have an opaque sound. The Tribute inputs are amazingly transparent as well as measure great. The CCS load sounded very much like the Tribute input transformer.
Just thinking...
Gary
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