I also like the BA-3 front end as a preamp. Boards available from diyaudio. No feedback, 20db or so of gain, 24V rails.
For my system, I need some gain in the preamp.
With a LCR design some described a change in tonal balance with the different levels of attenuation you get!
Is it a myth ?
Is it a myth ?
BTW why not a buffer à la BUF 03 with a pot ?
Is it transparent enough with good soundstage or just made for outputt buffer for a source ????
Is it transparent enough with good soundstage or just made for outputt buffer for a source ????
If you do use a "passive" then your system does need to be "suitable".
By that I mean you'd need to have relatively low Z output(s) on your source side, and then an attenuator with less Z than the amp's load.
Also, not all passive attenuators are the same.
I am not a fan of what is essentially a discrete potentiometer approach.
I prefer and use a "discrete stepped L" attenuator. This requires a "fancier" switch, and runs all signals through exactly two resistors.
It's about as clean as one can make.
DACs do not need or require GAIN, and most do not need a BUFFER to drive an amp.
You are adding electronics that unless they impart some harmonic subjective benefit (possible) are only going to add distortion, it can not reduce it.
If you are driving a pretty low Z load, or a very long cable, perhaps a buffer would be good. Beyond that all that almost any DAC needs is to reduce level.
It's fairly easy to test.
Just hook the DAC direct to the amp, pick a CD that you KNOW is recorded rather low, and play it. Is it TOO low? If not, then everything else you play will be too loud! If anything is too loud, then you need to DROP the signal level. No reason to INCREASE the signal level and THEN drop it!?!? 😀
Perhaps with hyper low sensitivity speakers, in a large room, with low input sensitivity amps, and the desire for rather loud listening, gain might be good - but you had best have enough headroom in the amplifier if this is the situation...
BUF03s in my view sound like ca-ca... there's a new buffer that is an IC to replace the LH0004(?) hybrid buffer, probably a better bet for an IC buffer.
If I needed a buffer, I'd build a discrete JFET buffer... 😀 Probably would sound nice.
There are a whole bunches of neat buffers here on DiyAudio... Keantoken has one that I recall, there are "diamond" buffers too... cool stuff...
By that I mean you'd need to have relatively low Z output(s) on your source side, and then an attenuator with less Z than the amp's load.
Also, not all passive attenuators are the same.
I am not a fan of what is essentially a discrete potentiometer approach.
I prefer and use a "discrete stepped L" attenuator. This requires a "fancier" switch, and runs all signals through exactly two resistors.
It's about as clean as one can make.
DACs do not need or require GAIN, and most do not need a BUFFER to drive an amp.
You are adding electronics that unless they impart some harmonic subjective benefit (possible) are only going to add distortion, it can not reduce it.
If you are driving a pretty low Z load, or a very long cable, perhaps a buffer would be good. Beyond that all that almost any DAC needs is to reduce level.
It's fairly easy to test.
Just hook the DAC direct to the amp, pick a CD that you KNOW is recorded rather low, and play it. Is it TOO low? If not, then everything else you play will be too loud! If anything is too loud, then you need to DROP the signal level. No reason to INCREASE the signal level and THEN drop it!?!? 😀
Perhaps with hyper low sensitivity speakers, in a large room, with low input sensitivity amps, and the desire for rather loud listening, gain might be good - but you had best have enough headroom in the amplifier if this is the situation...
BUF03s in my view sound like ca-ca... there's a new buffer that is an IC to replace the LH0004(?) hybrid buffer, probably a better bet for an IC buffer.
If I needed a buffer, I'd build a discrete JFET buffer... 😀 Probably would sound nice.
There are a whole bunches of neat buffers here on DiyAudio... Keantoken has one that I recall, there are "diamond" buffers too... cool stuff...
Thanks bear,
It was a long time...🙂 !
You know I'm more and more deaf, basicly I need a volume pot which is transparent between my amp (100 K inputt) and my AYA DAC (TDA1541, P. Rogic outputt stage) ! Single ended.
The datas of my Yamaha looks good... but between some datas and sound qualities there is sometimes a gap, so in my mind I look Something which is not the weak link to swap the said "bad" Yamaha Pre it is the 80s' cx-2 and not the best older C-x2...
It was a long time...🙂 !
You know I'm more and more deaf, basicly I need a volume pot which is transparent between my amp (100 K inputt) and my AYA DAC (TDA1541, P. Rogic outputt stage) ! Single ended.
The datas of my Yamaha looks good... but between some datas and sound qualities there is sometimes a gap, so in my mind I look Something which is not the weak link to swap the said "bad" Yamaha Pre it is the 80s' cx-2 and not the best older C-x2...
Well any of these super low distortion preamps could well be a step up from where you are now...
Perhaps you want to try my test? See if you need gain or not.
The less high frequencies one can hear, the less important these things become. 🙁
_-_-
Perhaps you want to try my test? See if you need gain or not.
The less high frequencies one can hear, the less important these things become. 🙁
_-_-
Well I have already one of my ear with a notch at 6k or 8 k, don't remember exactly !
I don't need gain but more Something to controll the vouleme attenuation, maybe a unity gain buff and a pott for just impedance adaptation should be enough ; the goal being : transparent with no phase problems, good soundstage (at least not influence on it). I used to look at 5687 tube with input and outputt traffo but too expensive, and not sure the noise floor to be low enough (I should be around 100 dB with my DAC, not measured though..).
Of course if a pre with transparent sources sélections (all dacs), it is the icing on the cake ! La cerise sur le gateau !
I don't need gain but more Something to controll the vouleme attenuation, maybe a unity gain buff and a pott for just impedance adaptation should be enough ; the goal being : transparent with no phase problems, good soundstage (at least not influence on it). I used to look at 5687 tube with input and outputt traffo but too expensive, and not sure the noise floor to be low enough (I should be around 100 dB with my DAC, not measured though..).
Of course if a pre with transparent sources sélections (all dacs), it is the icing on the cake ! La cerise sur le gateau !
in this price I was also advised this by a friend : Smash DHT Preamplifier Kit | Bottlehead
but long road to here, tubes are fragiles, and noise floor as said is maybe...
I believe at the end I risk to spend 500 in red wine if I continue to not find Something good enough at this price !
but long road to here, tubes are fragiles, and noise floor as said is maybe...
I believe at the end I risk to spend 500 in red wine if I continue to not find Something good enough at this price !
I went down the passive road trying all sorts of pots and attenuators, including the transformer based designs. The LCRs are leagues better in my opinion. If you're only using a DAC for a source, even better. Haven't noticed any change in tone with change in volume. You do notice the inky black background; all you hear is hum from your amp in that regard. And also the bass is better than with the myriad tube preamps I've tried. I have also tried four different LCR designs (Lightspeed, Hornshoppe's The Truth, DIY Paradise) and the Stereo Coffee example is the best of the bunch. It seems to work with most amplifiers so long as input impedance is above 50k (I think).
Here's another opinion from one who has been down a similar path to me:
Over the last decade I’ve searched for a better sounding replacement for preamps. Passive volume controls proved promising with some amps, so I stocked the Sonic Euphoria and Django early on. I've listened through a dozen different resistor and transformer-based passives since then: some my own constructions including Sowter, S&B, Slagle, Opera, then other trade-ins such as Goldpoint, Promitheus, Music First, Silk/ Parmenter. They all have their own character and to my ear are compromised by magnetics, switches, and tens of metres of extra wire in the circuit path. I didn’t hear a potentially better solution until I bought Lightspeed’s LDR-based volume control. The Stereo Coffee kit proved more open and dynamic again, with the benefit of input switching without sound-degrading switch contacts.
And finally, for a bit more on the Stereo Coffee design, see attachement.
Here's another opinion from one who has been down a similar path to me:
Over the last decade I’ve searched for a better sounding replacement for preamps. Passive volume controls proved promising with some amps, so I stocked the Sonic Euphoria and Django early on. I've listened through a dozen different resistor and transformer-based passives since then: some my own constructions including Sowter, S&B, Slagle, Opera, then other trade-ins such as Goldpoint, Promitheus, Music First, Silk/ Parmenter. They all have their own character and to my ear are compromised by magnetics, switches, and tens of metres of extra wire in the circuit path. I didn’t hear a potentially better solution until I bought Lightspeed’s LDR-based volume control. The Stereo Coffee kit proved more open and dynamic again, with the benefit of input switching without sound-degrading switch contacts.
And finally, for a bit more on the Stereo Coffee design, see attachement.
I ve used a stepped attenuator in front of a Pass F5 (100k input impedance but only 25W). With 90 db sensitive speakers I could get enough volume but not enough weight and slam. But the F5 has only 15db gain. Active pre added weight and dynamics...even though the volume increase was not needed. A buffer didn't help.
Just my experience...but this is a relatively low wattage, low gain amp with a high input impedance used with mid-sensitivity speakers in a large room.
My experience is very similar, though think mine is actually an F4 clone with a few more watts. Whatever, there's almost no volume at all with the LCR, and not enough even with an active tube preamp and 15dB of gain. It only came alive when I added a preamp with 27dB of max gain. Speakers are reasonably sensitive, using Visaton B200 drivers, which are supposedly 93dB or so, with a filter to tame to top end.
I would love to be able to run the LCR with the Pass clone, but that's not going to happen without modding the amp and not sure what that involves. So using a Naim clone instead. The LCR unit also works fine with some other amps I have lying around.
I would love to be able to run the LCR with the Pass clone, but that's not going to happen without modding the amp and not sure what that involves. So using a Naim clone instead. The LCR unit also works fine with some other amps I have lying around.
Well, the f4 is a buffer amp (no gain), so it only amplifies what you give it. And the voltage swing dictates the wattage output up to point.
The burning amp 3 (BA-3) is basically the F4 sans input buffers with a gain module (BA-3 front end) in front of it. If you were to add that gain module to your f4 you would be able to use your LCR.
The burning amp 3 (BA-3) is basically the F4 sans input buffers with a gain module (BA-3 front end) in front of it. If you were to add that gain module to your f4 you would be able to use your LCR.
The F5 (an amp I really like) is as you said, 15dB gain, "normal" amps are ~26dB. So, you need to make up about 10dB. However, in some cases you don't need the extra swing, it depends on your system/speakers.
Running an F5 direct into horns that do ~109dB 1W/1m and having a lmidbass that does ~100dB 1W/1m and using a ~26dB gain power amp on the mids, VOILA! magique!! Automatic level matching and no attenuator needed! 😀
No pads on the HF driver either
Incredible synergy.
The LDRs, iirc add some 2nd harmonic, but that may be "just what the doctor ordered". Also getting them to adjust linearly is another matter too. And, come to think of it, I think I recall from the discussions on the LDRs that they vary in distortion
wrt level...
"...if it sounds good, it is good..." Count Basie
Running an F5 direct into horns that do ~109dB 1W/1m and having a lmidbass that does ~100dB 1W/1m and using a ~26dB gain power amp on the mids, VOILA! magique!! Automatic level matching and no attenuator needed! 😀
No pads on the HF driver either
Incredible synergy.
The LDRs, iirc add some 2nd harmonic, but that may be "just what the doctor ordered". Also getting them to adjust linearly is another matter too. And, come to think of it, I think I recall from the discussions on the LDRs that they vary in distortion
wrt level...
"...if it sounds good, it is good..." Count Basie
the ba3 front end can run off the 24v rails of the f4 inside the same case. Literally they are made for each other. Inexpensive to build, assuming you have a set of 2sk170/j74 around.
You should really do this, shame to not use the f4 or at least see what it is capable of. Another preamp made for the f4 is the impasse...it's a tube preamp. I don't do tubes except in guitar amps but there is info on diyaudio.
Sorry, but a two cents question :
If my DAC ha no DC blocking cap : is there tipology of pre who can also avoid input cap for DC blocking or must I get a pre with an input cap ?
Is there also today good chips for volume control (à la Acuphase) better than the best pots or ladder ?
If my DAC ha no DC blocking cap : is there tipology of pre who can also avoid input cap for DC blocking or must I get a pre with an input cap ?
Is there also today good chips for volume control (à la Acuphase) better than the best pots or ladder ?
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