b-1 and attenuator
my two cents- and at least two dollars in paper-someone answer this poor guy's question with a definitive suggestion*
source
preamp
volume control
buffer
amp
best config in my opinion so as not to load down the sources, minimize the noise from the attenuator(gain before) and easiest load with which to drive the amp-this is my 2 cents
now, someone
put me out of my misery
my two cents- and at least two dollars in paper-someone answer this poor guy's question with a definitive suggestion*
source
preamp
volume control
buffer
amp
best config in my opinion so as not to load down the sources, minimize the noise from the attenuator(gain before) and easiest load with which to drive the amp-this is my 2 cents
now, someone
put me out of my misery
Re: b-1 and attenuator
This would be the ultimate solution. The only problem left, is that unfortunately my preamp doubles up as a headamp, so adding the volume control after the preamp would not work, as the phones outputs would not be attenuated.
http://www.amb.org/audio/beta22/
rob lenk said:
This would be the ultimate solution. The only problem left, is that unfortunately my preamp doubles up as a headamp, so adding the volume control after the preamp would not work, as the phones outputs would not be attenuated.
http://www.amb.org/audio/beta22/
Anyone looking for a good attenuator solution may be interested in this one also - I see they offer a resistor kit for 20k values.
http://glass-ware.stores.yahoo.net/netcjstat.html
Please don't ask whether to buy carbon or metal film
just kidding
http://glass-ware.stores.yahoo.net/netcjstat.html
Please don't ask whether to buy carbon or metal film
just kidding
Guess whos back .
I have decided to keep my headamp as a headamp, lets ignore that for now.
Back to the situation, im going to build a B1 for my new F5, but i need a small amount of gain to drive the F5 to full power, the output voltage of my dac is only 1.5v.
What would be a good way to do this, keeping it very simple?
.I have decided to keep my headamp as a headamp, lets ignore that for now.
Back to the situation, im going to build a B1 for my new F5, but i need a small amount of gain to drive the F5 to full power, the output voltage of my dac is only 1.5v.
What would be a good way to do this, keeping it very simple?
rhysh said:Guess whos back
I have decided to keep my headamp as a headamp, lets ignore that for now.
Back to the situation, im going to build a B1 for my new F5, but i need a small amount of gain to drive the F5 to full power, the output voltage of my dac is only 1.5v.
What would be a good way to do this, keeping it very simple?
Build a B3 ?
Nelson Pass said:Do you mean for sale, or for schematics?
RENO HIFI will sell you a FW B3. Nelson needs to eat too.
http://www.marksammut.com/List.html
Babowana said:
Do you have a BIG room . . . ? Don't worry too much. Be brave
My DAC has also only 1.5V and my speakers have 8ohms 84dB only.
My system goes through DAC >> B1 >> F5 >> 84dB speekers.
Fills up my room space of about 75 cubic metres.
>>
I have a average 13' x 12' x 10' room here, into 91dB speakers. Im coming from an amplifier with over 10x the output power, so getting the most out of the F5 will be somewhat important.
Hi,
an amp gain of +15dB and speakers of 91dB will give good volume from a 1.5Vac source.
If you want, try using the B1 alone to drive the F5. I think you will find it too loud for most listening without attenuation.
It needs another 6dB to 8dB of gain to get the amp to clip from a 1.5Vac source. but this will give loud music that you will only occasionally require.
Try it and decide.
I'm using +28dB into 86dB speakers without attenuation from a 300mVac source (Quad FM4) and it's too loud for most uses. It's sending ~ 1/2W to the speakers.
an amp gain of +15dB and speakers of 91dB will give good volume from a 1.5Vac source.
If you want, try using the B1 alone to drive the F5. I think you will find it too loud for most listening without attenuation.
It needs another 6dB to 8dB of gain to get the amp to clip from a 1.5Vac source. but this will give loud music that you will only occasionally require.
Try it and decide.
I'm using +28dB into 86dB speakers without attenuation from a 300mVac source (Quad FM4) and it's too loud for most uses. It's sending ~ 1/2W to the speakers.
multiple outputs on the b-1
andrew
i've been thinking and studying rc constants for the two power amp options I have(db systems 6m@47k ohms input impedance or a dynaco st 70 @ 470k ohms input impedance) and came up with a question I was hoping you could address
I want two isolated outputs from a B-1-
why wouldn't I just do two sets of output cap(10uf), series resistor(1k ohm) and parallel resistor to ground(221k ohms) in parallel from the ouput of the buffer?- would this load down the buffer?
I want to drive a powered sub and an amp for my main speakers-
your thoughts?-
thanks again for your ideas about rc and input impedance from the other day
andrew
i've been thinking and studying rc constants for the two power amp options I have(db systems 6m@47k ohms input impedance or a dynaco st 70 @ 470k ohms input impedance) and came up with a question I was hoping you could address
I want two isolated outputs from a B-1-
why wouldn't I just do two sets of output cap(10uf), series resistor(1k ohm) and parallel resistor to ground(221k ohms) in parallel from the ouput of the buffer?- would this load down the buffer?
I want to drive a powered sub and an amp for my main speakers-
your thoughts?-
thanks again for your ideas about rc and input impedance from the other day
If one of the outputs is for a bass only speaker then the other output must be for a speaker without bass output.
The bass only output could double up as bass only or full range if the 10uF is a good quality film capacitor.
The mid/treble/satellite output can use a much smaller (affordable) cap since it does not need to pass very low frequencies. Somewhere between 220nF and 1uF may be suitable as the DC blocking cap.
I prefer three octaves below required roll off frequency to ensure as much of the audio signal gets through to the Power amp. I settle for about 2.5octaves to save money.
Remember the option on bypassing the output cap when you know the Power amp already has DC blocking in-built. That's three outputs per channel.
The bass only output could double up as bass only or full range if the 10uF is a good quality film capacitor.
The mid/treble/satellite output can use a much smaller (affordable) cap since it does not need to pass very low frequencies. Somewhere between 220nF and 1uF may be suitable as the DC blocking cap.
I prefer three octaves below required roll off frequency to ensure as much of the audio signal gets through to the Power amp. I settle for about 2.5octaves to save money.
Remember the option on bypassing the output cap when you know the Power amp already has DC blocking in-built. That's three outputs per channel.
b-1 multiple outputs
thanks guys for the input(excuse the pun!)
both outputs are intended to be full range- x-over happens in the powered sub- Rel Strata- lovely piece-
anyone out ther know if the st 70 would have a problem with rel's preferred method of hookup which involves taking a high level input directly from the speaker binding posts of the main amp(lt +/ rt + and one -) to the input of the sub amp - they do this to best mimick the main amp's characteristics- I'm sure its a very high impedance(think megaohm resistors) to get voltage but no current draw- the question of compatablilty is if the dynaco would be bothered by the connection
thanks for your thoughts
r
thanks guys for the input(excuse the pun!)
both outputs are intended to be full range- x-over happens in the powered sub- Rel Strata- lovely piece-
anyone out ther know if the st 70 would have a problem with rel's preferred method of hookup which involves taking a high level input directly from the speaker binding posts of the main amp(lt +/ rt + and one -) to the input of the sub amp - they do this to best mimick the main amp's characteristics- I'm sure its a very high impedance(think megaohm resistors) to get voltage but no current draw- the question of compatablilty is if the dynaco would be bothered by the connection
thanks for your thoughts
r