hello,
I am searching for a tube line preamplifier schematics. Does anybody knows a very good sounding designs? I do not have any tubes so i have no limitation on that.
thank you
I am searching for a tube line preamplifier schematics. Does anybody knows a very good sounding designs? I do not have any tubes so i have no limitation on that.
thank you
pre tube
I built this preamp, and I assure you that sounds really good and it 'easy to build.
with some modifications it can operate at low voltage
http://www.pcb-audio.com/circuiti-stampati/schema-gomes.jpg
w w w . p c b - a u d i o . c o m
I built this preamp, and I assure you that sounds really good and it 'easy to build.
with some modifications it can operate at low voltage
http://www.pcb-audio.com/circuiti-stampati/schema-gomes.jpg
w w w . p c b - a u d i o . c o m
hi,
it don't need to be low voltage. I had made a Piaa tube preamp before.Also i can make any transformar needed. I need a line tube preamplifier with low gain, 2-3 would be fine. It will be connected to my diy mosfet amplifier and speakers.
http://www.diyaudio.com/forums/multi-way/189710-my-new-diy-speakers-project-2.html
it don't need to be low voltage. I had made a Piaa tube preamp before.Also i can make any transformar needed. I need a line tube preamplifier with low gain, 2-3 would be fine. It will be connected to my diy mosfet amplifier and speakers.
http://www.diyaudio.com/forums/multi-way/189710-my-new-diy-speakers-project-2.html
Depending on budget you might even want to consider something like a 26 dht transformer coupled line stage.. Low gain (4dB or so) low output impedance, and no concern about leaky coupling caps or long LF time constants putting DC into your solid state amplifier.
The down side is complexity and cost. I'm incidentally running such a pre-amplifier in my system.. Check out the 26 pre-amplifier thread in this forum..
Other good possibilities would be Salas 6V6 based line stage, and SY's Heretical..
The down side is complexity and cost. I'm incidentally running such a pre-amplifier in my system.. Check out the 26 pre-amplifier thread in this forum..
Other good possibilities would be Salas 6V6 based line stage, and SY's Heretical..
Hi,
With some friends we have built a tube based I/V converter for DACs wich does not need a preamp.
greg
With some friends we have built a tube based I/V converter for DACs wich does not need a preamp.
greg
what do you think about this design?
http://www.diyaudio.com/forums/tubes-valves/128936-my-6922-e88cc-preamp.html
http://www.diyaudio.com/forums/tubes-valves/128936-my-6922-e88cc-preamp.html
Far too much gain? A voltage gain of around 20 would only be needed with a very low output source or a very high input power amp.
Quote:
Far too much gain? A voltage gain of around 20 would only be needed with a very low output source or a very high input power amp.
I'm really confused here. Too much gain? Do you not have a volume control in which to adjust the level? Can you not make the necessary adjustments to achieve the volume level that is to your liking? Made a 12B4 line stage and the volume control setting was usually around 1:00 for the level that I wanted. Another line stage with more gain would result in a volume control setting of say 10:00 for the same level. Please do tell me what I am missing here. My distortion analyzer results were practically the same despite volume control setting. Are you trying to say that a line stage with lower gain will result in lower distortion? If so my test results have not come up with the same conclusion.
Far too much gain? A voltage gain of around 20 would only be needed with a very low output source or a very high input power amp.
I'm really confused here. Too much gain? Do you not have a volume control in which to adjust the level? Can you not make the necessary adjustments to achieve the volume level that is to your liking? Made a 12B4 line stage and the volume control setting was usually around 1:00 for the level that I wanted. Another line stage with more gain would result in a volume control setting of say 10:00 for the same level. Please do tell me what I am missing here. My distortion analyzer results were practically the same despite volume control setting. Are you trying to say that a line stage with lower gain will result in lower distortion? If so my test results have not come up with the same conclusion.
What you're doing is knocking down a signal twentyfold, then reamplifying it twentyfold. That inevitably adds noise and distortion, the reward for the extra expense and heat of those stages. Now, one could certainly get the distortion and noise pretty low, but not to zero. So, what's the point? A 12B4 linestage will have considerably lower gain, closer to the 0-10dB one generally needs in a linestage rather than the 26dB of the ECC88 linestage that was linked.
See Pano's excellent article on gain structure.
See Pano's excellent article on gain structure.
maybe try this:
http://www.tubecad.com/Product_PDFs/9-Pin_Stereo_Rev_C.pdf
You can also buy a pcb board to make building it easier. For a tube.. maybe 6CG7... don't spend much on them. I see many for 10 bucks a pair on ebay buy-it-now... auction nr. 230676674156 looks like a nice deal 😉
If you need less gain then I don't know what else to recommend except what sy writes above is best advice.
http://www.tubecad.com/Product_PDFs/9-Pin_Stereo_Rev_C.pdf
You can also buy a pcb board to make building it easier. For a tube.. maybe 6CG7... don't spend much on them. I see many for 10 bucks a pair on ebay buy-it-now... auction nr. 230676674156 looks like a nice deal 😉
If you need less gain then I don't know what else to recommend except what sy writes above is best advice.
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Can you please look at this preamplifier. What do you think?
DIY ECC802S (12AU7 / ECC82) Vacuum Tube SRPP Preamplifier
Without the cathode capacitor the gain is 7.
Can anybody explain why on all the tube designs the volume control is before the preamplifier and not after or between the tubes?
thank you
DIY ECC802S (12AU7 / ECC82) Vacuum Tube SRPP Preamplifier
Without the cathode capacitor the gain is 7.
Can anybody explain why on all the tube designs the volume control is before the preamplifier and not after or between the tubes?
thank you
YAS'M* - Yet Another SRPP Module! Without the cathode capacitor you get poorer PSRR, but it might still be OK as the supply is well decoupled. The pot will get noisy due to grid current eventually and the valve will lose its bias when the wiper lifts off the track. Even worse in the fancy switched version. SRPP works best when driving the exact impedance it was designed for, so not ideal for a general purpose line stage.
You might get lower distortion with the frame-grid type JJ ECC82, rather than the ECC802S which despite the more fancy name uses a conventional valve structure.
* with apologies to Driving Miss Daisy.
You might get lower distortion with the frame-grid type JJ ECC82, rather than the ECC802S which despite the more fancy name uses a conventional valve structure.
* with apologies to Driving Miss Daisy.
+1
You can not go wrong with a 9pin Aikido. The all-in-one version is even nicer if you do not want to worry about PSU.
hi,
finally i made this preamp: DIY ECC802S (12AU7 / ECC82) Vacuum Tube SRPP Preamplifier
the preamplifier sounds good but i have two problems and i need your help.
1.i have a mute relay at the preamp output (see first picture). when i power on the preamp the relay is in mute condition for 10sec. after 10sec it connects the output to the power amp input. when this happens i have a loud thumb from the speakers.I try to change the 10sec to 15 sec without any difference.
2. even when the preamplifier is working and i press the mute a have a thumb when the relays goes to mute on state.(when it grounds the power amp. input). When it goes to the mute off there is a little thump.
that two are a big problems for me because in most cases when i power up the preamplifier the power amplifier is already on. (it is already on because i use it for home cinema too with the home theatre bypass feature of the preamp)
can you show me how to connect the mute relay and possibly what resistors i need to use?
finally i made this preamp: DIY ECC802S (12AU7 / ECC82) Vacuum Tube SRPP Preamplifier
the preamplifier sounds good but i have two problems and i need your help.
1.i have a mute relay at the preamp output (see first picture). when i power on the preamp the relay is in mute condition for 10sec. after 10sec it connects the output to the power amp input. when this happens i have a loud thumb from the speakers.I try to change the 10sec to 15 sec without any difference.
2. even when the preamplifier is working and i press the mute a have a thumb when the relays goes to mute on state.(when it grounds the power amp. input). When it goes to the mute off there is a little thump.
that two are a big problems for me because in most cases when i power up the preamplifier the power amplifier is already on. (it is already on because i use it for home cinema too with the home theatre bypass feature of the preamp)
can you show me how to connect the mute relay and possibly what resistors i need to use?
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in most cases when i power up the preamplifier the power amplifier is already on
Have the power amplifier turn on only after the line stage is on and stable.
End of noise.
in most cases when i power up the preamplifier the power amplifier is already on
Have the power amplifier turn on only after the line stage is on and stable.
End of noise.
High-End tube Line-stage with 6DJ8
Here schematic pre-amp (Line-stage) with 6DJ8 (ECC88).
Know gives a great sound!
Enjoj!!
Hi korabetsni!
Here schematic pre-amp (Line-stage) with 6DJ8 (ECC88).
Know gives a great sound!
Enjoj!!
Attachments
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