Hi everyone,
I need your help to understand what is the difference between the 2 .
what i mean is this : what happens to the signal ( in my case +/- 1 v from the DAC ) , before it goes to the F6 amplifier .
what the signal looks like after being passed through them , in terms of volts , gain , db , etc ... i read many post , article , and i didn't find clear explanation for newbies like me .
.
I need your help to understand what is the difference between the 2 .
what i mean is this : what happens to the signal ( in my case +/- 1 v from the DAC ) , before it goes to the F6 amplifier .
what the signal looks like after being passed through them , in terms of volts , gain , db , etc ... i read many post , article , and i didn't find clear explanation for newbies like me .
.
ok, but if one has no gain, what happens to the signal , if 1v goes into the B1 , what comes out ??
.
.
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B1 will do 1V in 1V out.
If you don't need added gain then B1 is probably the better choice, if you do need gain then B1 isn't gonna work for you.
I have both B1 and a modified BA3 in one case. I use either depending on how much gain I need.
If you don't need added gain then B1 is probably the better choice, if you do need gain then B1 isn't gonna work for you.
I have both B1 and a modified BA3 in one case. I use either depending on how much gain I need.
ok, but if my 1v in , still 1 v out , what do the B1 , if voltage remains the same , freq will too , amp too , whats happens to the signal ??
something will happens , otherwise what is the B1 for ??
it look's like newbie words , because i am, Tank's ...
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something will happens , otherwise what is the B1 for ??
it look's like newbie words , because i am, Tank's ...
.
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Besides impedance matching, the theory is if you don't need gain to reach your normal listening levels, then less active and passive components in the signal path will allow more of the pure recording to reach the amplifier then out to the speaker.
B1 is mostly used as a separate volume control that can be hooked up to any power amp, instead of having to add a volume control to every amp you own.
Less is more if done correctly.
Hope that answers your question.
B1 is mostly used as a separate volume control that can be hooked up to any power amp, instead of having to add a volume control to every amp you own.
Less is more if done correctly.
Hope that answers your question.
Classic high-fidelity elements :
Audio Source |
DAC , CD-Player, Computer with audio card and many others...
+
Line preamplifier |
A) passive
Ok solution if Audio Source with high gain at his output
just volume resistor potentiometer or better switch, Light depended resistance ,
autoformer volume control all's with buffer ( signal is not make stronger= amplify)
Transistors are used to share at the output signal who are in harmony with power amplifier
give them impedance power amplifier need to play large frequency range bandwith from low 20Hz to high 22 KHz and more.
If impedance is not adapted by the buffer to the power amplifier music have "short" bass and high's frequency losses.
B) active
semiconductors are used to amplify boost small signal make them higher
gain level at the output for power amp input's
+
Power Amplifier |input impedance match to preamplifier , output impedance match to speakers
+
Speakers | impedance match to power amplifier output : 4,8,16 Ohm's
Idealy we don't need active preamplifiers or passive buffers because DAC or CD-player
source gain level and his impedance are perfectly adequate for power amplifier input....but in many cases that not happen.
Active preamplifiers and passive buffers bring flexibility to play with different audio sources and power amp's
of your choice and preserve recorded music integrity.
Best regards 🙂
Attachments
The B1 is a Buffer (a source follower), which is to say it produces a lower impedance at the output. The Firstwatt F4 is the same maybe reading about it will help. Schiit Audio also has a product called Saga which as a tube buffer. Lower output impedance stops parasitic capacitance such is long runs of cable or amp inputs from sucking off all the top end because it allows more drive current, but no voltage gain.
My go:
Buffer means no gain (Uin = Uout) but lower impedance (Zin > Zout).
Impedance denotes the ratio of voltage over current and in real circuits it is always finite.
If the stage after the preamp draws lots of current from the preamp when fed with a voltage (i.e. it has low Zin) the output voltage of the preamp will sag. How much it will sag is expressed by Zout of the preamp. Low Zout means low sag.
Impedance of an inductor or a capacitor is dependent on frequency. For a capacitor its absolute amount goes down linearly with frequency and capacitance. That's why LBHajdu writes cable capacitance sucks off the top end.
Buffer means no gain (Uin = Uout) but lower impedance (Zin > Zout).
Impedance denotes the ratio of voltage over current and in real circuits it is always finite.
If the stage after the preamp draws lots of current from the preamp when fed with a voltage (i.e. it has low Zin) the output voltage of the preamp will sag. How much it will sag is expressed by Zout of the preamp. Low Zout means low sag.
Impedance of an inductor or a capacitor is dependent on frequency. For a capacitor its absolute amount goes down linearly with frequency and capacitance. That's why LBHajdu writes cable capacitance sucks off the top end.
ok, now I am getting it more clear ;-)
the output Z of my DAC is 200 ohms , will an B1 do any "good" ?
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the output Z of my DAC is 200 ohms , will an B1 do any "good" ?
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then you are OK without B1.
(unless you want to drive excessive lengths of interconnect - that is)
(unless you want to drive excessive lengths of interconnect - that is)
The output-Z of the B1 (version 1) is over 1K so if you don't need volume just specs wise your better off without it just using your DAC with 200 ohms outputs. That said however I have to say I am not a big fan of DACs doing volume attenuation in the digital domain no matter how well they claim it's done (assuming your dac attenuates in the digital domain). On my Dragonfly USB dac something is just off and it's not getting my foot tapping at full volume however it's good with a pot in front of it for volume control. I am not alone here for example Srajan Ebaen writes on 6moons about the AURALiC Vega digital volume control:
Here is the link for attribution:
6moons audio reviews: AURALiC Vega
Here is the link for attribution:
6moons audio reviews: AURALiC Vega
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After all these read/talk , i think B1 has nothing to do in my setup , maybe an BOZ , but i would prefer think about my DAC output opamps to be upgrade , the TDA 1547 has some lack in that matter !!!
Tanks for all your help ;-)
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Tanks for all your help ;-)
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May I suggest you read through the article http://www.diyaudio.com/forums/diyaudio-com-articles/186018-what-gain-structure.html so you get a better idea if you need more gain in your chain or not?
Furthermore, the BOZ circuit clips quite early, at as little as 1V input iirc. There were some discussions on lowering its gain by lowering the load resistor.
Furthermore, the BOZ circuit clips quite early, at as little as 1V input iirc. There were some discussions on lowering its gain by lowering the load resistor.
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