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In Reply to: RE: Oh hello, but the poster said he tried the setup with a passive pre amp posted by keith_d on January 07, 2009 at 22:59:38
As you stated, this is not complicated. And based on the factors presented by the original poster I believe Ozzy is correct. Ozzy offered as a solution a passive line stages ***or*** preamps with lower gain.
Clearly, a passive line stage, while it may (or may not) ameliorate the problem, in Brian's case, it is not the solution to excessive loudness too early in the volume control range. This is because his speakers (98 db) are far more sensitive than most and his amp ramps up to full power with 1/2 a volt. However, as Ozzy said (and I offered it as well), a preamp with lower, or better yet, adjustable gain, is probably the key. Likewise an amp with gain control would be extremely helpful.
The problem as stated by the Brian is not an oddball problem; avoidable perhaps, but not oddball or uncommon. I have seen it expressed here and elsewhere *numerous* times. That's why there are amps available with selectable input sensitivity switches and pre amps with adjustable gain.
The fact that Brian's original post omitted or got some facts incorrect is not a big deal (happens all the time here and elsewhere in other forums) as long as he was able to come back (in spite of some sarcastic responses) and provide the needed information, which he did. We could then move *forward* and not continually dwell on past mistakes.
Robert C. Lang
Follow Ups:
> Ozzy offered as a solution a passive line stages
I believe Ozzy did not read the part where the poster said he tried a passive and had the same problem.
I see no reason to be credulous when something obviously makes no sense, but do let me know when you find those WMDs in Iraq. (The two matters are related in terms of lack of any skepticism.)
You seem to be under the mistaken impression that *all* passive line stages give the same results in any given system. That is simply not the case. Passive are no more one size fits all than active pres. You don't necessarily rule out *all* passives simply because one did not work out. The poster could have tried a passive and failed to get the desired results but then tried a different passive and gotten a lot better, even satisfactory results.
I would venture that the Placette passive line stage or one like it with a 132 step volume control would work quite well, or, at minimum, much better, in Brian's system. On the other hand a less expensive passive line stage with 12 or 24 (typical for many) step volume control would probably fail miserably.
It's the *volume control* not just that it is passive (or active) that can make the audible difference.
Ozzy seems clearly capable of defending his statements if he so chooses (or bothers), but it is clear to me that his advice is on solid ground *especially*, but not only because, he suggested that Brian explore a passive line stage *or* (that you conveniently glossed over) a lower gain line stage. (By the way, Ozzy [and hundreds of others] have provided system descriptions in Inmate Systems. You might consider doing the same).
You can continue to play *gotcha* and cherry pick his (and others) suggestion because he "slipped up", in your view, and included "passive" as an *alternative* in his recommendation, but that speaks more to an emphatic negativity coming from you versus his and others attempts to be positive and helpful to resolve an all to common audio problem raised by Brian. Your choice.Robert C. Lang
Edits: 01/08/09
Gosh, this thread really makes sense.
It doesn't make any sense at all. Whenever someone suggested something the originator came up with another equally suspect alteration of the scenario. First the speakers were always too loud. Then they sounded thin, not always too loud. Then he already had tried a passive when someone first suggested that.
> he suggested that Brian explore a passive line stage *or* (that you conveniently glossed over) a lower gain line stage.
BTW, this "glossing over" is not relevant. A lower gain preamp would still have more gain than a passive. It's moot.
Now, you still have time to get back to helping solve the unsolvable problem - cos it's a moving target - and please ignore that a passive pre and 25 tube watts and even 95 db speakers do not always sound too loud...it's nutty.
First, the "target" has not moved for many posts now. Your deliberate insistence that the glass is always half empty and not half full has precluded you from seeing the answer(s).
I don't claim to be an expert on this issue so if others want to weigh in with error correction or clarification please do. But I do have extensive first hand experiences with passive line stages, active pre amps, gain adjustable and not, as well as amps that have gain controls
Sarcasm aside, of course, passive line stages have no gain, BUT certain passive line stage/amp combinations effectively have gobs of gain. If you mate a passive line stage with an amp, that, for example, has an input sensitivity of, say, .5 volts (significantly lower that the typical 2 volt CD source), that passive line stage will access (drive) full power of the amp with very little turn of the volume control. The "ponies" (power) were let out too quickly (Brian's situation).
Conversely, if that *same* passive line stage, is mated to a different amp that has an input sensitivity of, say, 2.5 volts (higher than a CD source), that passive line stage will not be able to access or all the power of the amp even if the volume control is turned up all the way. The amp is no less powerful, but the passive line stage, in this case, cannot tap all the resources of that amp. So, "ponies" are left in the barn. And hence the perception that the passive line stage does not get loud enough (and/or has poor dynamics--it's often a result of poor matching along with impedance and capacitance (long interconnect)issues.
Likewise, if you employ a "lower gain" or adjustable active pre amp (by the way, a passive pre amp is an oxymoron--passive line stage is the correct term), even though it still has gain, as you correctly said, you can still "spread out", for lack of saying it better, the access to the watts of a given amplifier, so that the ponies are released more slowly. So, in Brian's case the pre amp' volume control abruptly releases the amps power. If the gain was reduced by, say, 12 db or more, as could be the case with a "lower gain" pre amp the power release would not be so abrupt and unneeded power from the amp would not be accessed. Instead of a small turn of the volume control "releasing" watts, "milliwatts" would be released. The volume control would have to be turned quite a bit to access all the power. In this case a "lower gain" or adjustable active pre amp would "effectively" have less gain than a passive.
You have not seemed to understand this (I'm *not* trying to be nasty), which is why Ozzy was saying you were getting "gain" and "power" confused.
Anyway, what really makes this an issue for Brian is that his speaker's are extraordinarily efficient (98db) so that even 1 watt can be extremely loud. So, he has sort of a "perfect storm", of amp power, pre amp gain and high efficiency speakers that together are most certainly a problem for him.
Robert C. Lang
> he has sort of a "perfect storm", of amp power, pre amp gain and high efficiency speakers
Except the problem allegedly happened with two preamps, one active and one passive. What are the odds of that? (Please write to Sphile, TAS and the entire industry about its erroneous use of "passive preamp. Thanks.)
And for the record the problem presented definitely was altered once the dubious nature of the initial question was pointed out.
They're 98 db, I see. That's new.
Now, sometimes volume controls or attenuators don't have fine enough gradations. That's completely different, as I said, from "they're always too loud," or "the speakers sound thin."
Over and out.
Beginning with your first "shot from the hip" post,"What the hell is wrong with your preamp?", you have not once offered a sliver of positive input. Not a whit. Not a fragment.
Robert C. Lang
Edits: 01/11/09
I'm learning a lot from this, well trying to. I would think my pre and amp would be a good match for each other considering they are the same manufacturer. What I should do is talk to someone at Canary Audio, or at least send off an e-mail.
I initially posted here to get an idea of a good speaker for my amp, I was looking at the Vandersteen as there are a couple on Audiogon, or something similar. But I did point out the problem I have with the system being so loud while barely turning up the volume control. Again, I can turn the level down, it still sounds ok, but I'm sure I'm not getting the best from the amp if I can't turn the volume control past the 10 o'clock position and that's my goal, to get the most out of the amp.
The sound was never really veiled or thin until I tried the inline attenuators, and I tried them at the amp output and the pre out, it was basically the same result, poor sound.
I know I need better speakers regardless, I have close to 10k wrapped up in the amp, preamp, TT and cart as well as the phono pre. The speakers I've had for several years and they are basically a 4 or $500.00 speaker. They do rock and play music fairly well but I know I can do much better.
I don't even remember now if I originally asked if a less sensitive speaker is what I need. Should I be looking at sensitivity, input voltages, impedance, a combination? I am planning to do some more auditioning this weekend but ideally in home would be preferred. That being said I didn't want to buy new and pay full price but if I do find something that works and sounds great I'll go for it. My initial budget was in the 2k range but if I need to up that I will.
Again, thanks for all info, it's been very interesting...
Brian
I agree that since your amp and pre are from the same manufacturer there should be no compatibility problems, so focusing on the speakers makes sense, especially since you want to upgrade anyway.
****I don't even remember now if I originally asked if a less sensitive speaker is what I need.****
I believe this is the key and this is why both Ozzy and I questioned the intial spekaer sensitivity spec that was provided. The Vandersteen 2C would, for sure, would be more compatible in your system from a *sensitivity*, because it is speced (86db) at about 10 db less than your current speakers and it might even be less sensitive still. BUT it is recommended that the Vandersteen have an amplifier of a minimum of about 60 watts. That could present an audible problem for your amp.
I realize that home audition of speakers is tough for you because of your remote location. BUT I would *never* commit to a pair of new speakers without a home audition. You may need to work out a deal where you can buy the speakers with an ion clad money back guarantee. Or check out a manufacturer like Ohm Acoustics which have built their busines on the home trial model.
Robert C. Lang
Robert, I decided on a used pair of Proac Response 2.5, made an offer that was accepted, which are also 86dB but are rated for 20w amps. I have heard a pair in the past though with SS gear and thought they sounded great. From what I've read the Proacs work great with tube gear so I'll know next week sometime how these sound in my system. This will be my first true HiFi speaker so I'm excited but also know these are fairly old speakers and hopefully I won't get the upgrade bug even if I really like them.
I do appreciate all the help from you and the others, this is why I love the Audio Asylum, always lots of good advice and information though sometimes too much, but that's good. Thanks again and I'll post on how the Proacs sound after I give them a good listen.
Brian
Congratulations! I certainly would be interested in how it turns out for you. Keep us posted.
Robert C. Lang
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