Is my preamp useless?

Hi Bill, you had a wonderful system posted on this site, I'm sorry you felt the need to delete it. I have had my system posted for the past 4 years and fortunately have had no issues or problems, I hope that continues to be the case.

Charles, I fully understand your point as you know. Yeah, I am still confident :)

I decided to pull my system for privacy and safety concerns I don't want to get into here. I used to have mine posted and had an "issue". Sorry.

have you heard all possible permutations/combinations of amp+preamps that exist in the world? If not, then it is simply YOUR view that actives are always better than passives. Folks have been very happy about TVC preamps, which are considered to be passives.

Of course I have not heard everything. But I did go to school and got taught engineering principles, and if you look at my posts you will see I was careful to be talking about PVCs and not TVCs. So as far as I am concerned, your comment is a strawman, as you are attacking an argument I did not raise.

However we can have that discussion if you like...

I feel folks who come here for sincere audio discussions should post their system so that the other party can understand why the poster is so exited about his/her system.

Good call, Milpai.

Grannyring,
Thank You for the offer. But I am a bit away from you - near Cleveland. I would be eager to know your system, in the first place. At least that will tell me why you felt your active would sound better in my system.

The next paragraph is for EVERYONE in general and not just you Grannyring.

I feel folks who come here for sincere audio discussions should post their system so that the other party can understand why the poster is so exited about his/her system. I think we all have gone through a certain phase of changes/upgrades, to arrive at what we like. So why not post your equipment here for others to see and then decide why the poster is exited about what he/she is recommending.

Grannyring,
I like your confidence, the problem is it is near impossible to account for another person's taste or preferences, very hard to do despite how good your active preamp may be.

Milpai, I offer to bring my active to your home and guarantee you will like it better. If not, I will eat one part inside my active :)

Are you close to MInnesota? I have no doubt you will say " I like your active better". No doubt.

Let's do the active throw-down!

Atmasphere,
With all due respect - have you heard all possible permutations/combinations of amp+preamps that exist in the world? If not, then it is simply YOUR view that actives are always better than passives. Folks have been very happy about TVC preamps, which are considered to be passives. I love my TVC. Does it mean, it will work in all systems? Heck no! Try my preamp with a power amp that has a sensitivity of > 1.5V and it will sound pathetic at best. If you have heard a passive that was introduced in a system that needed the gain, I am sure it would sound bad. At the same time, in my system I cannot introduce any source that gives out less than 2V.
So, it is all system dependent. A properly put together system can shine as much or better than an active line stage, if it used a passive preamp. It has been asked before - why would Nelson Pass make active line stage, if he likes passives? The simple reason could be - because people have behemoth loudspeakers, whose sensitivity is so low that they need tons of GAIN in their system. The amps that drive these loudspeakers are low sensitive amps, mostly >1.5V for full power.

^^ This post is incorrect, as the problem is not the control but the interconnect it drives, and of course the drive actually comes from the source- I explained this in my prior post.

Why is it then, when you put different active preamps in a system, the sound changes so much? Imaging changes, dynamics, contrast, etc... And a related question. I hear all the time comments to the effect of, a preamp can't add anything. It can only take away. If that's the case, how do account for something like image size getting much larger when switching from a passive or source with a volume control, to an active line stage? There are some big differences, not subtle ones. It makes perfect sense that a preamp can't add anything to a recording, but listening clearly proves otherwise.

Thanks for your thoughtful question! The first comment I have is 'compared to what?'. Is it that the line section is reproducing the image incorrectly or is it the passive? This really is very system dependent! Some line sections introduce colorations without any doubt, so I am usually careful to qualify my statements about what a line section should do with a phrase like 'properly designed' or similar.

IMO/IME it is a statement on how dreadful some line stages are that a passive control can sound better; if the line stage is designed and built correctly that simply can't happen. But in real life it does so that says to me that there are a lot of marginal line stages in use otherwise this debate would not occur over and over.

Going direct like the OP can do, will not add or subtract anything that the source is presenting. As his source (PSA) has perfect impedance match and voltage output to drive his Cary amps and the "interconnect".
Any active pre that is put between, will colour the sound, he may wish to do that but, he will also get way too much gain as well.

Cheers George

Atmasphere,

"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."

Looking at the post you referenced on what the preamp does, I have a question. I've heard this before, where people list these things and say that's all a preamp does, almost like its a trivial matter. (In general, I'm not singling you out.). Why is it then, when you put different active preamps in a system, the sound changes so much? Imaging changes, dynamics, contrast, etc... And a related question. I hear all the time comments to the effect of, a preamp can't add anything. It can only take away. If that's the case, how do account for something like image size getting much larger when switching from a passive or source with a volume control, to an active line stage? There are some big differences, not subtle ones. It makes perfect sense that a preamp can't add anything to a recording, but listening clearly proves otherwise. (Maybe no proves, but something is going on that's audible.)

^^ The quick answer is here:
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1426779273&openflup&16&4#16 (earlier in this thread).

The longer answer is that mathematically, no passive control is going to work perfectly as intended if it is driving an interconnect cable. The longer the cable the more noticeable the artifacts become (one solution is to build the control into the amplifier, which works very well). These artifacts can be so profound that a properly designed line section can actually sound more neutral.

Consider the source, which has an impedance, usually no more than a few hundred ohms and often quite a bit less. It is driving an interconnect cable. The lower the source impedance, the longer the cable it can drive and less artifact will be heard from the cable. If you install a passive volume control, essentially the source impedance driving the interconnect cable after the volume control (and the amplifier as well) is raised by the value of the volume control setting. This is often a multiple of the original source impedance.

The result is that the capacitance, inductance and resistance of the interconnect cable is no longer shunted by a low impedance (the source impedance). Instead the shunt impedance is much higher (the value of the control dominates this value and changes with the setting; you can see that as the control setting is changed it may be that the sound changes with it, and indeed many people experience this).

In this situation the resulting system is very sensitive to the issues of the cable and cable artifacts result. Anyone who has set up a successful system with a passive volume control knows this: the choice of cable in such systems requires careful selection as the cable artifacts are so easily heard.

There are other issues/phenomena; some are source dependent and others are amplifier dependent and so do not occur in all systems. Hence the extremely variable results that cause so many of these threads to exist.

so How and Why would a active premamp, tube or solid state sound better than a more direct connection.

Would capacitors, opamps in the signal stage of an active be better than a single resistor, or similar ldr, autoformers?

Every opamp, resitors, capacitors sounds different, possibly changing the sound to ones preference. Adding on your favourite powercord, interconnects, vibration control on these active component adds to the variables you hear, hence the difference in sound.

There is no right which sounds nicest, but the less the variables and carefully matching wiring and connectors will give the best, less molested sonics.

If one has a robust sounding front end, a passive will give equal or less coloured sound. Impendence matching and possible size of speakers room etc will cause possibly a lack of gain required for the amp and speakers to perform or rather not sound thin or dead.

Conclusion would be a matching choice of factors.

The best part is passives are way cheaper and can provide just as good a sound as a $10k or higher preamp.

There is just so much more ways to tune the sound say with capacitors in the signal. Some sound clean or bright or warm or more open pr more distant, the list goes on...

Add the same capacitor in a passive and the traits will start to show.

I see a lot of good replies especially Ralph's from Atmasphere.
Got any idea on how you are going to proceed slanski62?

Its useless dump it ASAP,

I was just kidding. I didn't think anyone would take my comment seriously.

Proselytizing, I don't think I do to much of that, as I'm not going blind, yet! And you know what mother used to say.

Cheers George

03-23-15: Zd542
"You may also know that Georgelofi is designer/builder of the Lightspeed Attenuator aka LSA."

I didn't know that. I take back my recommendation! lol. Get the Placette instead.

There was an A/B done here:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1276356977&openflup&1421&4#1421

And before that, he had a TRL pre.

Cheers George

Zd- I've never heard a Placette. It has some distinct features that would appeal to many (remote and/or input switching) but it's 2 - 2.5X the price of the LSA. Have you ever heard one? Regardless of George's proselytizing, it's a damn good product. The fact that he has made the circuit publicly available and provides support for DIY'ers makes me think he deserves some slack.

"You may also know that Georgelofi is designer/builder of the Lightspeed Attenuator aka LSA."

I didn't know that. I take back my recommendation! lol. Get the Placette instead.

Slanski- Glad you're still here! I used to own a BAT and would never talk them down. The question of passive vs. active has been the focus of much of the discussion, engendered by your comments about how much attenuation you are employing, which indicates excessive overall system gain, which has sparked the discussion about passive "pre-amps". You may also know that Georgelofi is designer/builder of the Lightspeed Attenuator aka LSA. He has very generously made his design available to the DIY community and also sells finished product. Obviously, he is a strong advocate of passive pre-amps and as many have stated, the LSA may be the biggest "bang for the buck" item currently available in high end audio. However, that does not guarantee that it is the best product to help realize your goals for your system. Maybe yes, maybe no. Another, similar option would be a tube buffer w attenuator/volume control. Others w more technical knowledge than me can tell you why that might be an appropriate option under certain circumstances.

Its just that one integrated amp.

Thanks folks. I didn't realize the Ayre has a passive line stage. That gives me another avenue to explore.

"Is the Luminous Audio Axiom a decent passive? It uses a conventional resistive ladder network for attenuation. It’s not a lot of money, so I won’t be risking much."

I haven't heard one myself, but the comments are generally very positive. If you can get one at a price that wouldn't involve too much risk, I say try it.

"Finally, there doesn’t seem to be a lot of love for BAT in this group. I expect their next to top-of-the-line (at the time) would be pretty decent. If you disagree, please tell me why. Thanks!"

There's one thing you need to understand when reading our comments. If you sat every single one of us down and had us listen to the same exact system, we would all hear something different. We all have different taste's, level of experience and beliefs in how we judge things. For example, I will immediately focus on the high frequencies. That's what's most important to me. I may miss a flaw in the bass, but one of the others may not. Some listeners will focus on bass and not so much the highs, like me. Some people like a lot of detail, some do not. Some are very picky about dynamic contrast, and others like coherency. At this point, you probably understand why I asked you if you had a technical background. That's another obstacle to deal with.

All of this means that you should use our comments as just that. Get some ideas from them. But under no circumstances, should you let us make decisions for you. That is something you must do on your own. We don't have to listen to your system, you do. Just because some of us don't care for BAT means nothing. If you like it, that's all that matters. Every single brand in existence has people that don't like them. BAT's no exception.

My recommendation would be to explore some of the other brands everyone here has recommended. You may come to prefer something else, or you may stick with what you currently have. There's no right or wrong here. It would just be unfortunate if you let us talk you out of a BAT preamp, if that's what you really like best. You shouldn't feel guilty or wrong about keeping something you like.

"Mr. Hansen of Ayre has stated that passives will outperform actives in suitable systems until one gets pretty high up in price for the active unit. There might be some truth in that.
Larryi (System | Threads | Answers | This Thread)"

I think you're right about Pass and the Ayre AX-7 has a passive line stage. His reason for not using an active is that he can't make something active that sounds as good for what the AX-7 sells for.

"03-23-15: Slanski62
Hi. Trying my DAC direct into my amps is certainly a good idea. I need to re-arrange my equipment so that my interconnects will reach both amps. I’ll try to do that some time this week."

This is the most sane comment in this thread so far, as it will cost nothing, and the gains could be massive.

Cheers George

Hi. Original poster here. I’ve been following this discussion with interest, and I didn’t know it would become so controversial!

A couple of thoughts:

Trying my DAC direct into my amps is certainly a good idea. I need to re-arrange my equipment so that my interconnects will reach both amps. I’ll try to do that some time this week.

Is the Luminous Audio Axiom a decent passive? It uses a conventional resistive ladder network for attenuation. It’s not a lot of money, so I won’t be risking much.

Finally, there doesn’t seem to be a lot of love for BAT in this group. I expect their next to top-of-the-line (at the time) would be pretty decent. If you disagree, please tell me why. Thanks!

+1 Frogman. If the OP is still around, remember that Frogman is a musician who is intimately familiar with what real instruments sound like and is fully committed to maintaining the tonality, drive and emotional impact of a performance. I think the takeaway message is try it, you might like it. If you do, you're way ahead of the game. If you don't, then you might want to consider a lower gain active.

And w respect to Nelson Pass' quote- I agree completely w Larryi. And of course there are lots of people who have systems that do not meet the criteria for using a passive. For example, George's LSA (a great product, I own one) does not have source switching or a monitoring circuit. All passives have limitations with respect to matching upstream and downstream components. If you are of the camp that believes that eliminating the need to attenuate the source signal is the "ne plus ultra" of system building, then go passive. If you have other criteria, then go with them. Think of system-building as a design exercise (which of course it is). There are always design trade-offs. ALWAYS. Even in "cost is no object" kit. Your final design will be based on how you value the different elements involved in each trade-off. If cost:performance ratio and transparency are your most important design criteria then an LSA might be the way to go, and then you need to base the rest of your design around that element. If a control center providing source switching and RIAA equalization in one package is your primary criterion, but you also really value transparency and channel tracking at low volume, you might want to consider a full-function pre w a phono stage and a TVC. If you have to have source switching, an RIAA equalization circuit and a remote, then you're probably going to want an active w a motor driven volume control. Add transparency to the list and it's going to have to be a very high end active. Etc, etc.

Slanski62, try the passive! The complaints about lack of drive, thinness or lack of involvement using a passive are completely system dependent. I am currently using a passive (Audio Synthesis) to Manley tube monos via 5m (!) of Nordost, driving 93db efficiency speakers and the results are fantastic. There will be exceptions to every "rule" proposed in the posts above which will depend on the particular components in your system, the particular passive you use, and your own sonic tastes. For instance, in my system, the passive brought significant improvements in the areas of transparency and tonal refinement with no loss of dynamic verve; there was a reduction in tonal fullness compared to my active pre, but the change was a welcomed change since my system was overly full sounding to begin with. You will never know the real answer to your question until you try it.

Re Nelson Pass and the integrity issue: Isn't it obvious that even if a manufacturer believed that a good passive is potentially superior to any active (I believe it can be) in a specific system, that given the fact that an excellent active will work well in many more systems than a passive will with its much more specific requirements, that this is the reason that a manufacturer such as Pass chooses to offer active preamps?

Slanski62, did I say "try it" :-)

Charles1dad,
That "specific" situation that you mention is correct, at least in my experience. Below are the situations when I feel that a passive will not work:

1. The source signal is very low
2. The amplifier sensitivity is more than 1V for full output
3. The speakers are less sensitive (less than 87 db and 4 ohms). Generally the BIG monsters with 10-15" woofers and 4+ drivers will most likely not work with passives.
4. You need more than 2 meters of ICs between source and amp
5. You need more than 15 feet speaker cables

I am sure that speaker wires also will make a huge difference. But I have not looked into that measurements.

On the other hand, if you carefully assemble a system around a passive - it is all bliss!

I do wonder if there is some missing context to what has been quoted from Nelson Pass. He is big into supporting the DIY crowd (puts schematics for First Watt designs on line). If he is talking to that crowd, he would be addressing those who tend to be very conscious of the price-performance relationship and would never spend really big bucks to get a tiny increment of improvement. I can see him telling them that MUCH more expensive actives are not worth it even though he builds ultra expensive actives for a different crowd that is not as concerned about price vs. performance.

Mr. Hansen of Ayre has stated that passives will outperform actives in suitable systems until one gets pretty high up in price for the active unit. There might be some truth in that.

This seems like a lot of banter for not much progress.

Like George has stated, it would be a simple process to run the DAC directly into the amp just to test the outcome. If the OP doesn't like what he hears, then a passive linestage probably isn't in his future. If he does, problem solved. Sell the BAT and pocket the $$. If he hsa other sources, then buy a passive linestage.

Pretty simple actually.

Shakey

"Zd542 I'm still trying to figure out what Nelson Pass has to do with all of this."

"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."

If you can't make out what he's saying, I can't help.

Cheers George

"So you can see, he's doing exactly what Nelson Pass is against"

I'm still trying to figure out what Nelson Pass has to do with all of this. And even if what you are saying is true, there are other aspects to a preamps design that effect sound quality.

Let him run then, if he did.
If he asked "Is my preamp useless"
Well yes then in his case, as he has to turn down his PSA source (risking bit stripping) so he has then some usable volume range on his BAT pre, even it then is in the negative of it's volume range.
So you can see, he's doing exactly what Nelson Pass is against, attenuating the source only to bring it back up again, (NOISE AND ALL) with the active preamp, and in his case the BAT is still in the negative of it's amplification. So it's no win on either component.

Cheers George

"03-22-15: Georgelofi

All I can say to this is, in the OP's case, how can $10k worth of electronics in the signal path with way too much gain + another set of interconnects, sound better that no preamp and interconnect at all. "

Al I can say about the OP, is that it looks like he's the smartest one here. Something tells me he ran from this thread like a burning building.

"03-22-15: Onhwy61
It's not really accurate to draw a conclusion about whether Nelson Pass thinks active preamps are the best solution for most systems just because the company with his name offers that type of product. At one point point Pass Labs offered an active loudspeaker, but now they only offer passive loudspeakers. Does that mean he really thinks passive designs are superior, or is it a reflection of marketplace realties? I don't know and only Mr. Pass and his cohorts can truly respond. Integrity can be expressed by making a high quality product that people want to buy. If you look at the vast number of products Mr. Pass has been associated with it's apparent that he is very flexible at doing that."

I think you're exactly right on that. You need to take each system and person on a case by case basis. In the end, everyone's system is probably going to be different. For me personally, I think a passive can be a great low cost solution for high end sound. But as you start going up in quality, I feel you get to a point where actives start to sound better. Obviously, not everyone would agree with me. And that's a good thing. No progress would be made is we all wanted the exact same thing. If we never had the experience of audio equipment we didn't like, we wouldn't own the same equipment we have today. The stuff we do like. The negative is what drives us to the positive.

All I can say to this is, in the OP's case, how can $10k worth of electronics in the signal path with way too much gain + another set of interconnects, sound better that no preamp and interconnect at all.
As his PSA can drive perfectly 100% the Cary mono's direct?

By reducing his source gain so much, and then to bring it back up again with the preamp so his has control over the volume, all he is doing is amplifying the noise floor as well.

It's ALWAYS best to get the full level signal from the source, not to attenuate it then only to bring it back up again further down stream.

Cheers George

Onhwy61,
Granted only Nelson Pass can fully explain his chosen product pathway decisions, not us. Do you really think he believes a passive is the best sonic solution and just builds actives for their popularity? Possible, but not probable IMO. Again if you personally feel passive/direct is better, no problem with that as it's your call. My own encounters say otherwise, that's just me. Choice is wonderful.

The point is he and his company advertise these SOTA preamps as best, the point is not that he makes them.

It's not really accurate to draw a conclusion about whether Nelson Pass thinks active preamps are the best solution for most systems just because the company with his name offers that type of product. At one point point Pass Labs offered an active loudspeaker, but now they only offer passive loudspeakers. Does that mean he really thinks passive designs are superior, or is it a reflection of marketplace realties? I don't know and only Mr. Pass and his cohorts can truly respond. Integrity can be expressed by making a high quality product that people want to buy. If you look at the vast number of products Mr. Pass has been associated with it's apparent that he is very flexible at doing that.

Grannyring,
Yes, integrity, that's exactly why I chose that word in my earlier post responding to George. The quote of Nelson Pass that George often cites does make sense and applies to "specific" situations. It doesn't fit all situations. If Pass felt passive were the ultimate solution, I believe he would devote his talent in that direction. Instead he put considerable effort,time and his exceptional talents towards "active" preamps. I don't believe he's playing games and making them to satisfy unknowing audio dummies. No, he builds them because he apparently feels they offer the best choice for superior sound quality, this defines his integrity and sincerity IMO. As we all can agree on, it's up to each listener to make fhis individual choice. Bill, your chef/fine dining analogy was a good one.
Charles,

"The OP has way too much gain as he has to lower the PSA volume (which could then be bit stripping), but is also in the negative volume on the BAT volume, which means it's not pre-amplifying but de-amplifying, which a total waste of source signal strength. It's like putting attenuators networks on a MC cartridge and then having to amplifying again, noise and all."

The BAT preamp lets you adjust gain for each input separately, as well as globally. So if you have a source with high gain that doesn't allow the volume to go positive, all you have to do is lower the gain on that one input the source is connected to.

Mr. Pass must in fact believe his best effort active preamps sound best. He must believe that. He is charging 10 of thousands for his best preamp effort and he advertises it as the best.

Integrity is also important here. I assume he has integrity and actually believes his mega dollar designs are his best sonic effort. If he felt a passive was best, surely he would spend as much time, money and effort designing a SOTA passive.

An active preamp is no more needed than a fine meal at an upscale restaurant. A simple piece of toast and an apple will take care of ones hunger without the need for an elaborate culinary effort. Sure, a passive is all that is needed. We get it. Gain blah, blah.....

I want to experience a delicious sonic event and I know this is extravagant. I know my active preamp is elaborate and beyond what is needed to play good music. But, I want to indulge and experience something beyond what is merely needed.

Mr. Pass is an electronics Master Chef and I have to believe he and many other audio Master Chefs design with a passion for the best. Master Chefs don't create merely for profit, no they create to deliver an unforgettable experience.

I do not believe companies and individuals making top dollar active preamps are doing so knowing that a $500 passive is just as good and all that is needed. Nor do they do it to just make money.

Integrity is at play here. What about the ads and sales materials these individuals and companies put out saying it is the best sounding and their best effort. Are they also now lying? Integrity. No, I don't really think so.
I think they have genuine passion and creativity for their products and the experiences they deliver to us.

George,
I happen to agree with your assessment of the OP's predicament, too much system gain. I definitely feel that passive preamps have their role and can also be very effective as the right solutions for certain systems. Furthermore I believe that in some systems Passive is the way to go, you have to try it and listen. No doubt that Nelson pass appreciates these certain situations himself. My point is that he would not take time to build actives if he felt they had no sonic advantages for many listeners. I would love the opportunity for Nelson Pass to share his thoughts on the merits of passive vs active preamps and why he chooses to build very high level actives.
Charles,

So why this public statement from him (again below), and it is in direct reference to what the OP is experiencing, TOO MUCH GAIN EVERYWHERE.
He has a prefect match with the PSA direct into his Cary's and eliminating all that active preamp gain. And I bet my life that the PSA has a beefier output stage than the BAT tube preamp has, so it should drive even better.

" 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 OP has way too much gain as he has to lower the PSA volume (which could then be bit stripping), but is also in the negative volume on the BAT volume, which means it's not pre-amplifying but de-amplifying, which a total waste of source signal strength. It's like putting attenuators networks on a MC cartridge and then having to amplifying again, noise and all.

What the OP should do is to listen to his PSA direct into his Cary amps as this has perfect impedance and voltage match.
Then see if he can at least equal or better this by putting an active preamp or passive preamp in the signal path.

Cheers George

So you feel you know his "true motive"? Profit? possible I would say(you can't substain a business without a profit). Or how about he honestly believes in what he chooses to build because he thinks it's a better sonic path. I imagine those customers who prefer to buy an active do so for improving their home audio sound quality, just a thought.I'd give Nelson Pass more credit for his commercial decisions than your conclusions. Build a product you genuinely believe in,do it right and the market sucesss will hopefully follow. It would seem he'd have these priorities in order.

Nelson Pass may believe active preamps yield better sound or why would he bother designing and building them?

To maximize profits, and market demand for believers of active preamps?.

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 does in a way, the First Watt B1 @ $1000.00, which is a passive with a simple two transistor buffer, to drive low impedance amps? If it were marketed as Pass Labs and gorgeous to look at as that line is, it may effect the $KKK preamp sales?.

Cheers George