honashagen OP38 posts04-30-2018 8:02amLast night I think I talked myself into thinking my new pass preamp was sounding good. I was fooling myself. It still sounds too forward to me. I really want to like it. Your Oppo has an output impedance of 100ohms, it will drive the 100kohm input of the DNA-1 in it's sleep, and just about anything else. And the Oppo at 2.1v out for RCA and 4.2v out for XLR. It easily has enough v gain for your DNA-1 poweramp, which only needs 800mV (.8v) in to give it’s full output wattage!!!!. As you can see, you don’t need anymore gain from an active preamp. Just look at the maths? Here is what Nelson Pass regards as his best sounding preamp, he says he can’t belive it didn’t make him filthy rich, and yes it’s totally passive untill the volume control hits 3 o’clock, then it becomes active for those that need the extra gain, "most likely because many of his poweramps are very low gain" but he also does say you take a hit in sound quality when 3 o’clock and over are used when it becomes active.
Yes your going to say, but he makes $$$$$$ preamps. He’s not a fool he likes to make money, passives don’t make money because you can’t sell them for $$$$K I prove that. " Nelson Pass: The Aleph L is a single ended Class A audio preamplifier combining new design thought
applied to traditional topology and the experience of twenty five years of amplifier design.
This preamplifier flows from a commitment to create the best sounding product: a simple
circuit with the most natural characteristic. The Aleph L integrates discrete Mosfet gain
devices and single ended Class A operation in a simple active/passive topology in order to
deliver the most natural sound possible. The Aleph L absolutely minimizes the number of
components in the signal path, and uses these only when necessary.
Unique to this preamp, patent pending, is a volume level control which combines the best
qualities of a passive attenuator and active gain circuitry:
At the 3 o’clock volume control position, the Aleph L offers a direct path from input to output.
The only component in the signal path is wire and switch contacts.
At positions below 3 o’clock, the volume control functions as a precision passive attenuator
using discrete resistor ladders.
Above 3 o’clock, active gain is added to the output signal in 2 decibel increments, for a
maximum of 10 dB.
As a result, you suffer the effects of active circuitry only when additional gain is necessary.
Another quote from him Nelson Pass, "We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more. Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up. Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control. What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection. And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp." Cheers George |
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bache129 posts07-16-2018 6:51am@honashagen you ask question , the answer is very simple
Absolutely no difference how much money you can spend , the pre amplifier -is device can change the sound in only one side- make sound worse. The ideal preamp just no change the sound quality Very true bache, the best preamp is no preamp if you can do it, with the source having it"s own digital domain volume control. But the trouble is a digital volume control in the source will start to "bit strip" (loose resolution) below 75% of full up, if you have to use it below 75% (because it’s too loud) then your next best to no preamp, is to leave it up full. And then use a passive volume control after the source, this way you retain all the resolution and most of the advantage of no active preamp in the signal path. Cheers George |
I don’t understand why you keep posting that.
Because it was the original balanced power supply direct coupled (matched) complimentry jfet buffer that Nelson designed for the Lightspeed. Afterwards it became (I believe the cruder) unbalanced supply re-configured capacitor coupled p channel jfet buffer (didn’t need to be matched) for the B1 Once again go away your stalking, also calling my product "thing"? you really need to see someone. Cheers George |
Too bad your thing isn’t balanced. It really limits it’s usefulness with a Pass amp Not really as "my thing" as you so quaintly put it, is used with many Pass amps they have rca as well, and those that don’t my customers use these http://www.cardas.com/adaptors.php as Nelson said above about rca v xlr. " Except for noise, it gives pretty much the same performance " and that noise is only becomes a factor with very long interconnects. Nelson also made an un-named buffer for "my thing", (with over 900 world wide I think it deserves a name) the Lightspeed Attenuator to drive one or two models of his amps that are low input impedance amps around 10years ago on diyaudio, a few years later to be sold as the commercial B1 buffer by itself to be used with other passives preamps. https://ibb.co/choBZSCheers George |
george, you just proved Ralph’s point with help from Nelson. Noise is audible. You need read and absorb better. I did nothing of the sort, I have always said the only advantage balanced has over single ended connection is for the cancellation of noise with long interconnect runs. Nelson Pass: " Except for noise, it gives pretty much the same performance " And we should get back on the OP’s topic " How much do I need to spend to get a preamp that sounds better than no preamp? The rest of your post is BS pushing your product.
As for me " pushing" my product sunshine, I have never bought it up in this thread unless asked specifically about it, all the other posts are for passive preamps in "general". And why these days active preamps are not needed in many systems, as there is already too much system gain without an active preamp adding more gain. Quote: Nelson Pass again! my god he’s eveywhere! Cheers George |
Looks like someone didn't like what I posted and got it removed, it will come back once looked at by admin, with if any modifications done to it so it's not so insensitive to their feelings.
Cheers George |
tweak1
It could be that my system is 100% balanced, Isn’t everybody doing that by now? Here is Nelson Pass’s take on balanced vs single ended. When asked by an owner what sounds better on his X350.5 On diyaudio.com Nelson Pass The one and only Join Date: Mar 2001 "Except for noise, it gives pretty much the same performance, and this is because the inputs are summing junctions, and single-ended inputs are merely another balanced source with ground as the (-) input." Cheers George |
balanced lines offer less coloration even if they are only 6" long
6" This is false, your either hearing things or your biased toward your own retail preamp product. In many cd players or dacs I've seen the balanced output is just an added opamp changing the "real' single ended circuit to balanced. Same goes with the input of many poweramps, which btw are single ended output to the speakers. The only time balanced is better from source to to pre, or pre to power is for noise cancellation with interconnect over 5mts> Cheers George |
When I inserted a Hattor XLR passive (sans buffer) between my Oppo 105 and my then EP 100.2SE amps(newest AA amp on its way) everything improved, especially bass
It could be that my system is 100% balanced, Isn’t everybody doing that by now? It was far more likely that you were experiencing "bit stripping" (a loss of resolution) when you went direct, as you were not using your Oppo’s volume control above 75% as the level was too loud to do this. And getting the better bass with the Hattor Passive pre you had you Oppos volume control up higher so there was no "bit stripping" going on. And as far as balanced sounding better than single ended this is a Furphy, the only time this may happen is if the interconnects are very long (over 5mts> 10mts) Cheers George |
mrdecibel
A veil has been lifted, the colorations are gone, and nothing is missing from using my 2 expensive preamps
Thank you George for steering me in this direction, as I always thought an active preamp ( with gain ) was absolutely necessary
No problems MrD, you've obviously got a good match if your hearing all that, now you've seen the light and just turning that passive up some more compared to the active. As Nelson Pass said: " Really - I’m
being serious here!. Maybe they are reacting psychologically to the need to
turn the volume control up compared to an active preamp." Cheers George |
Sorry broadwayjoe you are not even using simple terms, you simply have it wrong, accept it, if your going to state things, check to see if you have them right. The volume control from sources such as cdp ,dac, even computers ect do not drive the amp/s, their output buffers do (BIG DIFFERENCE to what you implied), which as I pointed out are more than up to the task, in most cases. Cheers George |
Generally a good stand alone preamp fed by the line level output of your source will be better than an amp fed directly by the volume controlled output of your source. Sorry but you have this wrong, volume controls in sources (cdp’s and dac’s) don’t feed the amp, they have output buffers after their volume control stage, and in many cases this buffer is the same or even better at driving an amp with lower output impedance and better current than some preamps outputs can especially tube preamps. Cheers George |
Nobody building an amp with a 25kR input impedance has any intention of it being fed with a 1kR+ source!
And why not, that's a input to output ratio of 1:25 And if you look your Pass B1 is 1kohm output impedance (linked circled in red) you really have lost it sunshine. Now please I ask nicely go away, or I'll report you for stalking. https://ibb.co/e32XTT |
You really have lost it, as I said 10k pot has at worst output impedance of 2.5k, a 1:10 ratio of that is 25kohm, so any amp with >25kohm or higher input impedance will be fine
Please go back to school or stay off the *****, it’s effecting you really bad, seek help.
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kosst_amojan
Like mrdecibel said, the perfect world doesn’t exist. Don’t cheery pick mrD, a perfect world does exist if the impedance’s are good, low output and high input (>1:10 ratio), and in most cases they are. Go away now, you are so annoying. |
Thank you mrdecibel, and that's exactly what I post "system (impedance) match" whether it's direct or with passive, which today is more the norm than the exception.
There are just some here that are protecting their interests, like a dog with a bone.
Cheers George |
yyzsantabarbara
I will buy 1 more of these amps to run in mono mode Hi yyzsantabarbara, just be aware when you bridge a stereo amp into mono, yes do do gain a lot more watts, but that’s where the advantages end, and the disadvantages start. 1: There is more distortion. 2: Lower damping factor (higher output resistance) which equates to less control in the bass. 3: Less ability to drive lower impedance’s of some speakers (maybe the Kef’s 3.2ohm in the bass.) To me if your single Ahb2 has enough watts for you to drive the Kef Blade, which aren’t that hard to drive at 3.2ohm min at 90db and a benign -phase angle, it will probably sound better than two bridged ones. If not I would look at another amp/s without doing any bridging. Cheers George |
Whatever Ralph. I'll do and say anything I feel is right, I know this sort of thing hurts your preamp sales and I'm sorry for that, but I'm not going to step around it as you would like me to.
Cheers George |
Ralph I’m not trolling, you can stalk me all you like, would you like me to start returning the favour?, you "try" to present facts your way, and I’ll do them my way, with whoever/whatever proof I have. |
You’ve lost it kosst, go and down another bottle. Go back to complaining about fins on the sides of chassis, you were almost believable then. |
kosst_amojan
A quote from an article for an active pre-amp. You’re ridiculous. You have totally lost it, or your on your second bottle, that quote is NOT from Nelsons active preamp, but from his stance on passive preamps. Here ’s the whole thing, once again for the aggro one. A Quote from the master Nelson Pass on passive preamps. Nelson Pass, We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more. Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up. Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control. What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection. And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp. |
Only a question: if you were happy with no preamp, why?
+1 Cheers George |
George , I tried to PM you, w/o success. If you could PM me,
Done. Looked it all up, and your right to go for the Lightspeed in this system. Your Adcom with 78ohm output impedance at 2.1v is a perfect match. Your Nuforce at 51kohm input impedance with 0.45v input sensitivity for full output, is also perfect. As you can see you only need 0.45v into your amp to give it's full wattage output, and you have 2.1v from your source, so you don't need an active preamp adding more gain. Remember what Nelson Pass said. Nelson Pass,
We’ve got
lots of gain in our electronics. More gain than some of us need or want. At
least 10 db more.
Think of it
this way: If you are running your volume control down around 9 o’clock, you are
actually throwing away signal level so that a subsequent gain stage can
make it back up.
Cheers George |
mrdecibel
@georgehifi I might be ready to try an LDR unit, so what do you think ? Enjoy ! MrD.
By all means Flick me a PM with your email address listing your components, and I'll send you all the relative info on the Lightspeed Attenuator, even a diy circuit if you've got the electronic skills and test gear. If all the impedance's and good, 90% of systems are, I guarantee you'll never look at an active pre the same way again. Cheers George |
I’m pretty sure that’s what I said, isn’t it? No you were putting ****on the fins, and I wasn’t. I like the fins, as I said " they look a lot better than a plain square box."!!!! http://www.audiocircle.com/image.php?id=151232 Geesh!#! read first, think, pause, then react. |
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Posted this up on the wrong thread, it was meant to be here.
These are two Hattor’s. Passive, which I believe you have, which what looks to be Kozmho switched volume control, which I believe is a fixed series resistor and variable ones to ground, which will vary it’s i/o impedance’s at different volume levels, best to me is ladder ones, where the series and shunt resistors work in opposites to each other to give a more constant I/O impedance https://www.audiocircle.com/index.php?topic=145833.0And the active buffered Hattor which used an opamp. http://mockingbirddistribution.mockingbirddistr.netdna-cdn.com/wp-content/uploads/2018/03/Hattor-Min...Here are some different ways of doing a volume control, quad matched ldr is a ladder https://www.stereo.net.au/forums/uploads/monthly_2018_06/Capture.JPG.93bbd2ce49060300b06abfd1a62ce8f...
Just found their site, they have an extensive range, of what looks to be well made products, including a tube one http://www.hattor.com/index2.html#ultimate
Cheers George
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honashagen OP
If so just put a bunch of your favourite preamps in series and the sound would just keep getting better! Yeah that would open the eye’s (ears), should just keep getting better and better until nirvana’s has been reached. https://ih0.redbubble.net/image.121918664.8304/ap,550x550,12x12,1,transparent,t.u3.pngtweak1536 posts05-28-2018 5:04amI just closed a deal for a Hatton passive XLR, so will see whether it improves on no preamp. If no glitches, I should have it by friday Can we know what your sources impedance and output voltage is and the power amps input impedance and sensitivity is, so there are no question raised? As you’ve posted in other posts that you have a tube/capacitor coupled output Raysonic source, which would not be very low output impedance especially in the bass, for your experiment to be conclusive in it’s outcome. Also do you have a link to this Hatton xlr pre, all I can find is stuff to do with bands/studio ect. Cheers George |
The best way to me, because it uses Sabre balanced + and - dac chip outputs, is to use the XLR output on the Oppo direct into a true XLR input poweramp. And use the Oppo’s volume control, hopefully it’s used at 75% or higher so there’s no risk of "bit stripping" This should be the ultimate in transparency and dynamics.
Cheers George |
I missed if those are being used going direct with the Oppo.
It is one case where going direct to amp with the balanced output betters the rca because the Oppo use a balanced output dacs in the Sabre which has + and - outputs in each channel, so it's naturally better to use it's xlr output than it's re-configured xlr to rca. Cheers George |
As I sit here listening with no preamp, it seems like common sense would tell you that if a preamp alters the sound from the source in any way it’s really a processor of some type. Right? To me this is correct, but I use the term colouration/distortions not processor. And that why all "preamp aficionados" have different views how all of them sound, as no two sound the same, and no one sounds like the proverbial "piece of wire" like going direct does. Also sources today and even yesterday have outputs that are just as good as most preamps, and better than some. Here’s another little gem from the audio god himself on passives: And going direct is even easier for the source. Nelson Pass:
Historically we have had a number of consumers concerned about input and output
impedances of equipment, but from our experience the concern is largely unjustified.
From the standpoint of input impedance, I can only say that it is a very pitiful source that
cannot come up with the 100 micro-amps of current needed to drive this input. I don’t know
of any tube circuit that doesn’t bias to at least 100 times this amount.
The output impedance needs to be low enough to drive the capacitance of a reasonably long
cable. How low does it need to be? I would say that it should be able to drive a 1000 pF
load out to 100 KHz. The worst case output impedance of the Aleph L will drive 1000 pF
with a -3dB rolloff at 225 KHz." Cheers George |
honashagen OP58 posts05-25-2018 9:42pmFrom Oppo tech:
The BDP-105 players will not lose resolution since they are 32-bit DACs. So they are the ideal solution if you want to go direct to an amplifier. This is from a discussion I had with Thorsten Loesch the designer/owner of the very hiend digital company AMR digital. " Turn down the volume even the tiniest bit using the digital volume control and the sound quality to a massive hit.
I have tried many times, the minimum attenuation in the digital domain possible seems to destroy the sound quality of any true high end DAC I have owned. This includes using PC software that claims to have a super duper digital volume control. " I and others I know also Wadia states the same that you can go down a little to 75% of full, maybe Thorsten has bat ears. Cheers George |
leotis
I am told by someone who should know that the digital volume control on the Oppo produces a signal that is not lossless. Correct it’s not lossless, If you had to used that digital domain volume control below 75% of full up because it was too loud, you may very well have started to "bit strip" the resolution, from 16bit down to 14bit to 12bit to 10bit ect the lower below 75% you went. The only way out of that one is to have a passive in between and leave the Oppo digital VC up full. Cheers George |
The direct drive amps I will use won't have output transformers and will put out 5000V to the panels.
Same, drive esl's from the tubes 5kv, mono blocks to keep the speaker wire short as possible, the trany's I mentioned were for the power supply side of things. I heard a pair of 57's driven like this and it was amazing, they had a pair of Magnat MP-02 Plasma tweeters from 12khz up. I now own them also and they are on my Monoliths from 12khz up. Same as these. https://www.ebay.com/itm/Magnat-Plasma-MP-02-ion-tweeter-massless-air-plasma-speaker-Plasmahochtoner...Cheers George |
Paul McGowan: My adamant stance against inserting a preamp between a high quality DAC like DirectStream and the power amplifier should be no surprise to readers of this blog. As well, my subsequent turn around embracing the exact opposite should lift no eyebrows either. But why would inserting an extra piece of gear in the signal path sound better than a more direct approach? How could this make sense? ....
Almarg: Makes sense to me. So if Paul McGowan can do an about face on this issue, at least under some circumstances, I guess I can too :-) But I believe that in general the opinion I expressed in my first post in this thread still stands:
Almarg: The burden of proof should always be on adding anything to the signal path that is not an obvious necessity. In this specific case a preamp is not an obvious necessity, and per George’s analysis (with which I agree) the odds appear to be in favor of that burden not being met. However, as others have indicated the only way to know for sure is to try it.
Good luck. Regards,
-- Al
Al, a smiggen of imagination here, did you know he made this about face Oct 2015, during the development period of his next to be released product in 2016 the BHK active preamps, hmmmmmmm? Cheers George |
Any one who is blind to the fact and doesn’t believe that an active stage has noise, distortions ect, and any increase in gain of that active stage also increases any noise ect coming into it and within it’s self. Your better to raise the passive master and let more of the source signal through, than to lower it and to raise the gain of the active stage and keep the master low, as your throwing away the sources signal level only to make it up again with added gain of the active stage. I’m over saying it, and so is Nelson Quote NP: " Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up. And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp." Cheers George |
So its not clear where you are going with this, but clearly it fails to address my prior post if that was your intention. I’ve addressed everything that need to Ralph. Once again simply. "Any! active stage/s introduces noise hum and distortions, increase their gain and you increase those as well." So it’s best to use as "most" as you can from the "passive" Master volume (which has virtually no noise hum or distortions), and use as little as possible "gain" from the active stage. Couldn’t be simpler. Nelson Pass: " A “passive preamp” - just an input selector and a volume control. What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection." Cheers George |
The best active buffer with or without gain, is going to generate distortions and noise, no matter how good it is. Nelson Pass back that up when hes says: " A “passive preamp” - just an input selector and a volume control. What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection. And on his hybrid Passive/Active preamp: " The only component in the signal path is wire and switch contacts.
At positions below 3 o’clock, the volume control functions as a precision passive attenuator using discrete resistor ladders.
Above 3 o’clock, active gain is added to the output signal in 2 decibel increments, for a maximum of 10 dB.
As a result, you SUFFER the effects of active circuitry only when additional gain is necessary."
Cheers George
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direct drive amps for my ESLs. Yes yes now your talking clio09
, I would like to do this myself on my Monoliths, have all the right tubes, tranny’s ect, but it’s dangerous to own such a amplification/speaker wire weapon. Like the 805 set monoblocks I built with 900v on the top cap, definable no beers and a good night sleep before doing any bench work on them, lethal. Cheers George |
Note: The words THE MASTER!! were added to my post after the fact.
I don’t care when it was added. As the "volume control" is always the "Master", just thought I’d drive it home to you. Clearly you don’t work with active line sections or you would know that. Of course I do, don’t be ignorant, if you increase the gain of an active stage you increase not just the signal what’s coming in but everything else including noise, rf ,hum any tube or transistor noise is also amplified when you add more gain to an active stage. Cheers George |
since the volume control (THE MASTER!!) has to be before the active gain stage in order to prevent overload. So the noise floor of a tube line stage if well-designed will be a constant. So the noise floor of a tube line stage if well-designed will be a constant. This is total BS, yes the "Master Volume" is in front of the active gain stage and should be at or around 2-3 o’clock for normal listening, 5 o’clock or nearly full for loud, and 12 o'clock for low listening. If the active gain stage has a "gain control" as in this case, and has it’s gain increased so then the "Master Volume" is at 9 o’clock for normal, this will increase noise, distortion and whatever other non linear distortions the active stage has, sent to the amp, hence to the speakers. Cheers George |
I never said to run the gain stage wide open and reduce it with the master, I said the opposite, who’s the **** now.
I said before to lay off whatever it is others have said you consume, as it's doing you no good.
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You can just put the gain control at some random point like 3:00, but is that the optimal point? Not clear. One would need to know a lot about the circuit design to make that call. I’m not surprised AI isn’t getting involved in the answer, as it can be quite complicated. It’s also why few amplifiers actually have gain controls (except for vintage ones, and that was because of the wide variety of speaker efficiencies back then).
I would have thought the least amount noise would come if the master is at or near full for loud listening, then the gain level if it is controlling the "tube gain" it’s then only increasing any noise to a minium level, as tube noise/distortion increases at the same rate as the gain will. Cheers George |
phomchick
Personally, I have retired my preamps (I have three to choose from) and have my DAC connected directly to my amplifier. It is better. +1, But there are others that live in denial, even if they can do with good impedance and gain matching. A buffer or gain stage added to a passive with good impedance and gain match can only add distortions/colourations. Cheers George |
