Hello Dirk,
many thanks for the advice! I often read that a certain pre doesn't fit to a certain power amp, so I just wanted to be sure.
Currently I have the 9,5 vdc setting and the first thing was to try not to swap the polarity (okay, I forgot it, to be honest
), and I liked what I heard. Now I'm hearing with swapped polarity and I like this setting too. I'm not sure, but maybe there is more space when hearing with "out of phase" but I still have to check it.
But first I have to go through my CD collection so fun is guaranteed
Cheers
Istvan
many thanks for the advice! I often read that a certain pre doesn't fit to a certain power amp, so I just wanted to be sure.
Currently I have the 9,5 vdc setting and the first thing was to try not to swap the polarity (okay, I forgot it, to be honest
), and I liked what I heard. Now I'm hearing with swapped polarity and I like this setting too. I'm not sure, but maybe there is more space when hearing with "out of phase" but I still have to check it. But first I have to go through my CD collection
so fun is guaranteed Cheers
Istvan
Hello Nelson, I live in the UK, so if I float the earth on a DH Labs power cord that I will use with the Meanwell that should be OK, also if the B1 is not grounded why would I get a possible ground loop. Thanks.
Hi all, I have KB1 between Purifi Eval1 amp and streamer/dac. KB1 works wonders on the amp. Without KB1 I find it dull sounding (compared to a Sonneteer Alabaster amp). It drives 4 Ohm monitor speakers that dip to 2 Ohm. That's the reason I went for the more powerful Purifi amp.
I use the volume control of the streamer/dac. The amp is set to low gain. That's more than loud enough in my small room.
What would be the the optimal volume setting for the KB1? I mean should I set it at max, at 70%, 50% or even lower?
Aim is to optimise output current for the monitor speakers.
I use the volume control of the streamer/dac. The amp is set to low gain. That's more than loud enough in my small room.
What would be the the optimal volume setting for the KB1? I mean should I set it at max, at 70%, 50% or even lower?
Aim is to optimise output current for the monitor speakers.
Even if Mr. Pass' answer disappeared, I read the email-notificationI swapped between in phase and out of phase, and I like out of phase more.
There seems to be a bigger stage, more dynamics, more liveliness (I use the Manzanita OB).
Is something wrong with me?
So - I'm glad to be here
Yeah, I read the opinions there short time agoMy tablet misbehaves when I reply sometimes.
My answer was "perhaps you want to ask that question over at Audio Science Review"
But they also don't like the ACA, so they are disqualified
Hi Dirk,Hello Plott,
I would say: Enjoy the sound! - whether in phase or out of phase...
I would trust my ears.
🦻
Cheers
Dirk 🙂
yes, that's exactly what I'm doing
Cheers
Istvan
Hello folks,
I wanted to bypass the Alps 50K pot to connect the B1 Korg in series between my Metrum DAC preamp which has already a volume control and the ACA Mini amplifier.
Assuming it's not as simple as just disconnecting the Alps and adding a 50K resistor in series to the B1 input.. My Preamp/DAC has low output impedance of only 100 Ohms. Tried the bypass with a 100K resistor and the volume control gets quite loud at about 10 o'clock or 1/3 of the way.. Concerned here about the impedance mismatch between the 3 components affecting audio performance. Only planning to use the Korg with one input for digital so fixing the input makes sense as I don't need 2 volume controls.
Have you guys tried the B1 Korg as a "buffer" only without a pot ? I find it warms up the ACA nicely for long listening sessions much less fatiguing for my old ears than the ACA mini connected straight to the DAC.
Any experiences with this?
I wanted to bypass the Alps 50K pot to connect the B1 Korg in series between my Metrum DAC preamp which has already a volume control and the ACA Mini amplifier.
Assuming it's not as simple as just disconnecting the Alps and adding a 50K resistor in series to the B1 input.. My Preamp/DAC has low output impedance of only 100 Ohms. Tried the bypass with a 100K resistor and the volume control gets quite loud at about 10 o'clock or 1/3 of the way.. Concerned here about the impedance mismatch between the 3 components affecting audio performance. Only planning to use the Korg with one input for digital so fixing the input makes sense as I don't need 2 volume controls.
Have you guys tried the B1 Korg as a "buffer" only without a pot ? I find it warms up the ACA nicely for long listening sessions much less fatiguing for my old ears than the ACA mini connected straight to the DAC.
Any experiences with this?
Yes I did.
My B1K is in a special "switch unit" enabling various configurarions with all sorts of sources and various preamps, and a part of it that concerns us here means I have regarding the B1K the choice between:
Long story short, in your case just put per channel say a 20k load (resistor) at the entry of the B1K to replace your pot, between signal and ground.
I hope this helps
Claude
My B1K is in a special "switch unit" enabling various configurarions with all sorts of sources and various preamps, and a part of it that concerns us here means I have regarding the B1K the choice between:
- line direct (direct feed from source without any atenuation - or pot- , what you want if I read you correctly)
- line entries with classical pot in the way to attenuate the signal
- line entries with a simple "attenuator resistor network with 2 only positions", ideal IMHO for digital sources, in my case enabling 0dB and -28dB attenuation at the flick of a simple commuter, fine volume tuning being done betwen these steps digitaly by the source.
Long story short, in your case just put per channel say a 20k load (resistor) at the entry of the B1K to replace your pot, between signal and ground.
I hope this helps
Claude
100% same conclusionsI swapped between in phase and out of phase, and I like out of phase more.
There seems to be a bigger stage, more dynamics, more liveliness (I use the Manzanita OB).
Is something wrong with me?
Quote :
"Assuming it's not as simple as just disconnecting the Alps and adding a 50K resistor in series to the B1 input".
The R is not in series to the input, but runs from Line to Ground in parallel!
If in series then indeed you could have some possible impedance mismatch and load problems sides B1K... If you put the R in teh right place, there is no reason you shoudl experience a problem based on the data your provided.
The loudness is another matter, linked to your gain chain. Indeed, the B1K has a lot of gain, possibly more than you will need and possibly in your set up a problem for a 2V source (and a prob anyway if using these 2V inputs due to distorsions once passed 4V at the B1K output). In that case you can't use wisely your volume control, better put a voltage divider instead of a pot at the B1K input, to give you more usefull digital vol control.
Nearly there, 2 more resistors (and replacing accordingly the 2 others you fitted) is all you need, but calculate what you really need as you don't want to overdue your attenuation.
Good luck
Claude
"Assuming it's not as simple as just disconnecting the Alps and adding a 50K resistor in series to the B1 input".
The R is not in series to the input, but runs from Line to Ground in parallel!
If in series then indeed you could have some possible impedance mismatch and load problems sides B1K... If you put the R in teh right place, there is no reason you shoudl experience a problem based on the data your provided.
The loudness is another matter, linked to your gain chain. Indeed, the B1K has a lot of gain, possibly more than you will need and possibly in your set up a problem for a 2V source (and a prob anyway if using these 2V inputs due to distorsions once passed 4V at the B1K output). In that case you can't use wisely your volume control, better put a voltage divider instead of a pot at the B1K input, to give you more usefull digital vol control.
Nearly there, 2 more resistors (and replacing accordingly the 2 others you fitted) is all you need, but calculate what you really need as you don't want to overdue your attenuation.
Good luck
Claude
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so 2 resistors required? one on the line and on on the ground for each channel?
OK, again...
2 different matters, impedance andB1K load on one side and gain chain (volume setting) on the other
Quote: "Where shall the 20K resister be mounted?"
=>NOT where you did. Signal Line input goes into B1K Line input (as it should), Signal Ground to Ground (as it should), and your 20k R goes between Ground and Line. So in parallel, not in series
Do that first, the rest is more complicated and you will need to address that first to go step by step safely.
Then you will still have a gain chain problem, that is the volume adjustment issue you mentioned... should that really be one to you of course. That is adjustment of volume. I suggest you consider digital volume control doing low attenuation levels, running in a fixed attenuation thanks to a voltage divider. A bit like a volume pot that is frozen in a given position, hence made out of 2 Rs per channel. Both attenuations together are IMHO a very good puristic non expensive way to address volume on a digital source with volume adjustment.
To determine what voltage divider you need, you need first to address the attenuation you want.
To do that, run the lowest recorded music you have at the loudest volume you are likely to use in your HIFI system.
Note at what volume position you are on your source. I have no clue on that of course, depends on your sensitivity etc.. it will be like -XdB.
Could be for example say -20dB at your source, as you only use one. Or -6dB, or whatever. Call it -XdB.
Based on that you can calculate your voltage divider, consisting of 2 resistors per channel. None is the ones you already have!
You want total input impedance to remain say around 20k (or 50k or whatever you want), and need to calculate the R network to achieve your -XdB attenuation with it.
That way you will use your volume to the fullest and where it works best if digital.
Oh, keep a safety margin in case of a party, take say 6dB extra margin. So if you found X to be say 20 with your listening tests, keep it to 14 or so. So instead of -20dB just -14dB. If your room gets much bigger, you get deaf, or move to low efficiency LS, don't worry, all you may need worts case is swapping again the Rs... no prob.
Completely confused now, right, LOL!
Just start by putting your R in the right place first...
2 different matters, impedance andB1K load on one side and gain chain (volume setting) on the other
Quote: "Where shall the 20K resister be mounted?"
=>NOT where you did. Signal Line input goes into B1K Line input (as it should), Signal Ground to Ground (as it should), and your 20k R goes between Ground and Line. So in parallel, not in series
Do that first, the rest is more complicated and you will need to address that first to go step by step safely.
Then you will still have a gain chain problem, that is the volume adjustment issue you mentioned... should that really be one to you of course. That is adjustment of volume. I suggest you consider digital volume control doing low attenuation levels, running in a fixed attenuation thanks to a voltage divider. A bit like a volume pot that is frozen in a given position, hence made out of 2 Rs per channel. Both attenuations together are IMHO a very good puristic non expensive way to address volume on a digital source with volume adjustment.
To determine what voltage divider you need, you need first to address the attenuation you want.
To do that, run the lowest recorded music you have at the loudest volume you are likely to use in your HIFI system.
Note at what volume position you are on your source. I have no clue on that of course, depends on your sensitivity etc.. it will be like -XdB.
Could be for example say -20dB at your source, as you only use one. Or -6dB, or whatever. Call it -XdB.
Based on that you can calculate your voltage divider, consisting of 2 resistors per channel. None is the ones you already have!
You want total input impedance to remain say around 20k (or 50k or whatever you want), and need to calculate the R network to achieve your -XdB attenuation with it.
That way you will use your volume to the fullest and where it works best if digital.
Oh, keep a safety margin in case of a party, take say 6dB extra margin. So if you found X to be say 20 with your listening tests, keep it to 14 or so. So instead of -20dB just -14dB. If your room gets much bigger, you get deaf, or move to low efficiency LS, don't worry, all you may need worts case is swapping again the Rs... no prob.
Completely confused now, right, LOL!
Just start by putting your R in the right place first...
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I assumed in the above your source was indicating volume level in -XdB format. So 0 dB is the loudest, -XdB is attenuated.
On some products you may not have that, but something like a volume from 1 to 10 or to 100, 1 being low level, 10 high level (=loud). Or perhaps just a virtual rotary knob without any graduations at all on it! For the above, you really need to find out the required attenuation in -XdB format.
If that's not the case it gets more complicated. Not a real issue, but in case you may not dispose of measurement tools and some practice perhaps, things get a tad more complicated... No worries, in that case you could still do with a multimeter and say your good old volume potentiometer to determine your required fixed attenuation level.
There are other ways of course, but with some equipment, or software knowledge (depending on your source), I will anyway let much wiser people here guide you while it is bedtime this side of the world...
On some products you may not have that, but something like a volume from 1 to 10 or to 100, 1 being low level, 10 high level (=loud). Or perhaps just a virtual rotary knob without any graduations at all on it! For the above, you really need to find out the required attenuation in -XdB format.
If that's not the case it gets more complicated. Not a real issue, but in case you may not dispose of measurement tools and some practice perhaps, things get a tad more complicated... No worries, in that case you could still do with a multimeter and say your good old volume potentiometer to determine your required fixed attenuation level.
There are other ways of course, but with some equipment, or software knowledge (depending on your source), I will anyway let much wiser people here guide you while it is bedtime this side of the world...