Nelson Pass may believe active preamps yield better sound or why would he bother designing and building them? He is known for doing much personal research and much prolonged listening sessions to test. I don't believe he's wasting his time. If he felt passives were the ultimate solution, that would be his primary focus, but it isn't. Perhaps like other listeners who've tried both options, he found that high quality actives provide better sound. It seems unreasonable he'd attach his name, reputation and effort to a component he finds sonically inferior.
it seems based on his actions he is a believer in an active preamp, yet he recognizes the benetfit of passives/direct connection under certain circumstances. It just seems if he truly felt passives were the better choice he'd be building them as part of his Pass Labs line, he is not. I'd say he has integrity and chose to build actives simply because they sound better to him. What other reason would he have to move in this direction? My 2 cents worth.
Charles, |
He makes a few models of poweramps that are at or below 33kohm input impedance, this then will have a ? for a passive to drive at 100% perfect impedance match.
But to counter that Nelson Pass does make his First Watt B1 preamp which is buffered passive preamp, that is just a passive pre with a unity gain simple two transistor active buffer, which then can drive these or other poweramps that are at or below 33kohm input impedance.
And yes he does make proper preamps that have gain and are $$$$ but he is a business man, and needs to make money.
In the OP's case he can drive his PSA dac direct into his Cary amps and have the prefect match with no preamp in the way.
Cheers George
|
"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."
He makes a good point. But I don't understand why Pass only makes active preamps. And they're not cheap. |
Robr45 hi, read again the OP's first post about the amount of gain he has, then read "gods" words below.
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 |
The lower you want to play music, the better preamp you need. Retaining resolution while attenuating the signal is no easy task. Throw in a bunch of other stuff and me thinks a good preamp is worth its weight in gold. |
"If he expressed some disappointment with it, that would be another matter. But we really won't know for sure until he tries a passive. You may be right."
That's just the thing. I think we all can agree that in this hobby ignorance is bliss. You don't know what you are missing (or not?) until you hear it (or don't?). Just because he is happy with the BAT doesn't mean he wouldn't be ecstatic with a better preamp.
Shakey |
"03-20-15: Mattmiller
That BAT preamp isn't adding anything in terms of beautiful tone or accurate highs. And at low volumes FORGET IT. I would get a AYRE preamp if you want to go Soild State."
The one thing I think we're forgetting here, is that the OP already has a BAT preamp and is very happy with it. So much, that his first choice was to upgrade to a better BAT preamp. Regardless of what our personal tastes are, the OP is the one who has to listen to his new preamp, not us. |
Your preamplifier is not only providing attenuation, but it also helps match input impedance to properly drive your amplifier- regardless of level.
Not saying a passive won't work, as your Cary amps input impedance is relatively high, but it is not accurate to say your pre is doing nothing but attenuating the source signal. |
That BAT preamp isn't adding anything in terms of beautiful tone or accurate highs. And at low volumes FORGET IT. I would get a AYRE preamp if you want to go Soild State. If you go tube I would switch from BAT to something a lot more engaging like a Modwright or Manley labs. The pre amp will make or break your sound and you can spend a lot of time and $$ getting it wrong. So I say YES to a pre amp in your system just find the one that works best for your system and ears. |
There is a Luminous Audio Axion II posted for sale right now. What's your collective opinion of it? |
"03-20-15: Shakeydeal
"The reason I do is because you usually have to buy a really good active preamp to get where it actually sounds as good, if not better, than a passive. Your preamp, in my opinion at least, is beyond that mark by a comfortable margin."
I don't agree with this at all. I have owned two BAT preamps, and several more actives which were far better than them. A good passive has beat every one of them. I would be willing to bet that the VK-52 would not fare any better."
I believe you, and there's nothing wrong with what you're saying. My post was meant to be personal opinion, not fact. The OP seems to be happy with his BAT, so I would expect a passive would be hard pressed to win him over. If he expressed some disappointment with it, that would be another matter. But we really won't know for sure until he tries a passive. You may be right. |
Thanks again for taking time to respond everybody. Looks like I have a lot to learn! |
A preamp does these things:
1) provide volume control
2) provide any needed gain
3) provide switching for various sources
4) control artifact from interconnect cables.
Of these the last is the least understood. Since you don't need any gain my recommendation is a buffered volume control. This is a passive control that has buffering circuitry with no gain that allows the control to work properly without artifacts being generated by the interaction that typically occurs between the volume control and the interconnect cable driving the power amp. |
As with anything audio, a LOT depends on personal taste and system compatibility, and therefore, comments about which types or models are good or not are just rough generalizations. I "tend" to prefer active tube units over the passives I have heard in my system and that of friends. I also like transformer coupling, which means that the linestage has a transformer at the output and the amp has a transformer at the input.
But, I have heard, and liked transformer-based passives too (Silver Rock). These sound vibrant, lively and deliver the kind of "dense" or saturated sound that I like. I also got to hear the Placette passive linestage (conventional resistor) and the active linestage in my system and preferred the active (I bought the active). My system is not ideal for passives, because of the requirement for a long interconnect between the linestage and amp.
In a friend's system, I heard a linestage built around a light dependent resistor passive. This was an ideal setup for a passive--short interconnects, low output impedance source and high input impedance amp. I liked the sound of the system, but, when we substituted a really nice tube linestage, the dynamics improved markedly. There were three listeners and we all agreed that the tube unit sounded better (including the owner of the custom-built passive unit).
Apart from the sound, some passives present practicality issues that should at least be considered before going that route. Many, particularly of the transformer variety, have too few stepped levels so that it seems like the ideal volume is always somewhere in between steps. To me, the steps should never be greater than 2 db, and 1 db is better. Most do not allow for balance control and most are not remotely controllable (getting the right setting matters a lot to the sound and instantaneous comparison
afforded by remote control is a requirement for that purpose).
There is a form of transformer-based passive that I have only heard briefly that may be of interest. It is one based on an autoformer (kind of transformer). There is a remotely controllable version from Bent Audio that gets around all of the practical limitations of such units--it is remotely controllable, has 1 db steps over a 70 db range and it can control balance. I have not heard it, but, it is based on the autoformer designed by Dave Slagle so it should be pretty good. If you are not technically inclined, you will need someone to custom build a linestage around the module you can purchase. The Bent Audio unit can be found at:
http://www.bentaudio.com/index2.html |
"The reason I do is because you usually have to buy a really good active preamp to get where it actually sounds as good, if not better, than a passive. Your preamp, in my opinion at least, is beyond that mark by a comfortable margin."
I don't agree with this at all. I have owned two BAT preamps, and several more actives which were far better than them. A good passive has beat every one of them. I would be willing to bet that the VK-52 would not fare any better.
Shakey |
You are right that the main function of a preamp nowadays is to attenuate the volume. It also provides better impedence matching for a wider range of equipment.
If you have powerful amps it will be a safer possibly avoiding the thin and weak sound.
Being that you are using a BAT tube preamp, it is very possibly addding colour, warmth and ambiance.
I have just added an LDR resistor passive preamp which is impedence adjustable. Eliminating the impedence mismatch problem. I found setting the impedence higher by a few will make the sound very clean and lacking some warmth.
All in all, i can live with it and sounds very good, well maybe slightly less 3D sounding but very very good. It replace a good tube preamp with upgraded teflon capacitors etc costing itself, more than the passice unit. Without these mods, i am certain the accuracy, bass etc for a passive LDR preamp is superior! Stock tube preamps bass is almost always more wolly and adds a little flavour. |
As other have said Slanski62, use your PSA dac direct into your Cary mono's, it will be an eye/ear opener, and you may sell your preamp. As for your phono stage, it's a pity the PSA does not have analogue inputs to except the phono stage. So purchase this cheap $49 passive that gives you input switching as well for everything. Then you can still go direct into your amp with your dac when you want the very best from your digital source. http://schiit.com/products/sysCheers George |
I have never met a passive that I could live with. The sound always seems weak and uninspired. |
"So if I try the passive route, what do I look for?
Thanks All!
Slanski62 (Threads | Answers | This Thread)"
Since you already have an outstanding preamp, I would say to make a commitment to get rid of it until you are sure that you have a definite replacement that you like better. The easiest way to try a passive, if you don't have a local dealer, is to call The Cable Company (fatwyre.com). They lend out audio components for you to try as demo's. That way you don't have to buy anything first, just to see if you like it or not.
I wouldn't get my hopes up on going with a passive, though. I like passives very much and recommend them on a regular basis. The reason I do is because you usually have to buy a really good active preamp to get where it actually sounds as good, if not better, than a passive. Your preamp, in my opinion at least, is beyond that mark by a comfortable margin. I see trying a passive more as a learning experience for you, than a serious effort to get better sound than what you have. But I still say try it. Its great experience, and you may end up using what you learn in a different system or situation. |
Preamp does more than control volume and source selection. A preamp is also the heart of a good system. It manages the interface between source and amp and interconnects. Even so, the preamp can be a trade-off if not wisely chosen. Without a preamp you may gain transparency and detail but you may lose body, drive and dynamics. |
Thanks for the responses. Fwiw, the rest of my system consists of Cary Audio 500.1 monos and custom speakers from Selah Audio. Cabling is Transparent Musicwave Super XLRs. I don't have a technical background.
So if I try the passive route, what do I look for?
Thanks All! |
"For me, the next component to upgrade would be the BAT preamp from a 52SE to a 53SE. But something occurred to me. I don’t listen loud. The gain on my PSA DSD is set to less than 100 and the BAT preamp is usually set between -20 and -10. So if my volume control is never set in the + range, is my preamp doing ANYTHING other than attenuating the volume and serving as a multi-input switch? Is all that Super Tube, single gain stage, zero feedback, high energy storage circuitry a waste of money?"
A preamp does quite a bit more than just adjust volume. Reading your post, it sounds like you may have a technical background. Is that the case? That may have an effect on how you deal with this, that’s why I ask. |
Yes, your preamp is absolutely useless. Just send it to me and I will dispose of it properly for you, free of charge. ;^)
Cheers,
John |
Another typical logical reply from Larry. Simply compare your system with the preamp and then running the direct stream into the amplifier and just listen and decide.you could try a relatively inexpensive passive like the Lightspeed and compare. Some audio systems will sound better with an active preamp and others will sound better without them. |
Get rid of your preamp and sell it to me for cheap and use passive volume control. It's more pure and transparent. |
I think you should do as Larryi suggested and run the PS Audio DirectStream direct into your amps and use its volume control. It's an excellent volume control and the quality does not diminish as volume is lowered. That way, the comparison will show you exactly what the BAT preamp is doing with it's associated cables.
If you don't have the latest Pike's Peak mod definitely download and install it! My guess is you will gain a fair amount of detail by bypassing the preamp, but you will lose any euphonic tube colorations. I did not find my particular DirectStream to need any tube colorations because the sound is relaxed and very musical right out of the DAC.
If you need analog inputs for your turntable or other sources I recommend you try a Luminous Audio Axiom II passive preamp with the Walker mod. You will find that there won't be much difference in sound quality running the PS DAC into the Axiom II and then into your amps... and it's very affordable! It will give you back your input switching for other sources and you can get a second pair of outputs if you like. Good luck! |
Larryi is right of course; try it both ways.
When I had the PWD, my system sounded better with the PWD at 100% and a pre; does the volume control on the DSD "shed bits" as believe the PWD did?
John |
The first step would be to just take the BAT out of the system and use the PS Audio volume control to see what that does to the sound. If it improves the sound, you at least know that some improvement is possible by going without the linestage. If the sound does not improve, it might be the case that the PS Audio volume control is at fault (some say attenuation in the digital domain is less desirable than analogue attenuation), in which case you will have to at least try alternatives.
Is the flexibility and remote control features of the BAT important to you? Will a passive have to include some of the features of the BAT? What kind of amps will the passive have to work with? Some additional information would be helpful. |
