Won't preamps become obsolete?

the question posed has many legs: quality of gain control in the CD player; impedence matching between the CD and the amp(s); whether or not you also run analog sources such as tuner, vinyl, tape, etc. There are a growing number of components trying to address these needs. Some are doing a better job then others. Some separate DAC's now sport some pretty good volume controls which will mate well with virtually all power amps ... however then you also need a good transport. Furthermore you need to address the usage issue ... do you also need a good A to D converter for the aforementioned analog sources? So far there aren't many made and even those that are out there aren't as advanced as the one box CD/Pre-amp units available. [unless they're modded] Total the cost of separates versus one or two box units and balance that against what you're getting out to see if you're on the right path. Then there is the spousal acceptance factor ...

jyprez...for about 350.00,you can send the 10a back to cj. and get the 10b upgrade.i did it last year and there is a significant resolution difference.the power supply is heftier also.

the question posed has many legs: quality of gain control in the CD player; impedence matching between the CD and the amp(s); whether or not you also run analog sources such as tuner, vinyl, tape, etc. There are a growing number of components trying to address these needs. Some are doing a better job then others. Some separate DAC's now sport some pretty good volume controls which will mate well with virtually all power amps ... however then you also need a good transport. Furthermore you need to address the usage issue ... do you also need a good A to D converter for the aforementioned analog sources? So far there aren't many made and even those that are out there aren't as advanced as the one box CD/Pre-amp units available. [unless they're modded] Total the cost of separates versus one or two box units and balance that against what you're getting out to see if you're on the right path. Then there is the spousal acceptance factor ...

Hi all:
I just put together the the DIYhifi tvc kit that uses the S&B transformers and I can report that they are very good. Especially at lower volumes. Specs and price for one at this site. A good value I think.

http://www.diyhifisupply.com/diy_kits/django.htm

There is also some good info a the S&B site above.

Bombaywalla...Thanks for the very interesting info. I can understand the advantage of a transformer for a passive preamp, where impedance matching can be a problem. Also, the ability to provide a little gain is nice.

Except for the impedance issue a resistor ladder "if done correctly" should be as good or better. The info shows good frequency response, but nothing about distortion. No idea of price either.

Eldartford,

You are correct in assuming that a TVC is a multitap audio xformer. If done correctly they provide excellent sound today. Xformer technology has come a long way since the days you remember & really excellent sound can be had at a reasonable price. Personally I have heard a very inexpensive passive TVC from Antique Sound Labs (when I was in Atlanta listening to single driver speakers. You did make a post on that thread - it's the last one) & it was quite impressive. Basically, it had no sound! Plus, there was really no loss of high freq. content that I could tell in the 3-4 hrs I listened to that system. I believe that ASL wind their own xformers in-house (China).
Other TVCs made by Stevens & Billington are supposed to be excellent. You can check the freq. response of the same at their website: http://www.stevens-billington.co.uk/page102.htm
I know that it is each to his own but do not under-estimate the sonic performance of a TVC until you have actually heard one! Stellar sonic results are very much possible today. You'll be surprised.
I also know that these days a # of tube amps (both manuf & DIY) use a lot of coupling xformers in them with excellent results. I *think* Art Audio is one such brand & there is a highly regarded DIY personality (Art Loetsch?) who uses coupling xformers in his designs.
IMHO. FWIW.

Blptwp...What is a TVC? I am guessing that it is a multitap audio transformer. I don't understand your comment about superiority vs a resistor divider. It was a great step forward when interstage transformers went away, and here you are puting a transformer back into the circuit! Transformers have limited frequency response, and if they include core material (like iron) they create distortion. Power amp output transformers have extra windings applied to grids of the output tubes as many dB feedback to correct these transformer deficiencies.

Sounds like the preamp, or for that matter the amp or speaker (possibly the extra ICs), doesn't have flat frequency response. (If the preamp is capacitively coupled, the input impedance (Z) of the amp may be too low.)

In otherwards, it is possible that one is compensating, sonically, for the other component(s).

Steve
SAS Audio Labs

I don't think so. The reason are several fold, of which two are:

1) Separating the first stage from the following stages relieves the problem of frequency dependent feedback through the power supply. This lessens sonic interactions between stages, resulting in better, more lively, sound quality.

2) Hum and noise are reduced without compromising the integrity of the design.

Steve
SAS Audio Labs

Further to my comments regarding volume control and transformer volume control (TVC). I like to add that I have the same TVC as in the Bent Audio passive box, but as built-in in my tubed phono stage, custom made by Kevin Carter of K&K Audio. I don't have a linestage. In my phono stage, I have a set of output for vinyl and another set for CD. The output for CDP goes directly to the TVC, so it's like a passive linestage without gain. Eventhough I don't listen to CD, I have this CD output just in case I get a CDP later. I have tried a CDP in this set up, it has more than enough gain. Most CDP have output of 2 volts. For my phono stage, it has 65dB gain, my cartridge is the Koetsu Rosewood Signiture with 0.6 dB and I have more than enough gain. Let me tell you, the dynamics is unbelievable with TVC. Standard volume control is resistor based, which suppresses high frequencies, bass and dynamics, TVC dosen't do that at all. I have numerous phono stages in the last 20 years and this is the best of them all.

Why is it that each and everytime I bypass the preamplifier the sound becomes thin and sterile. It is true that there seems less "garbage" in the sound (less noise, less distortion), but there is also loss of bloom and spaciousness, which to me are very important omissions.

I have gone this route and in the end a good Preamp is the way to go.

No they will never go away.

And Viynl is comming back huge.

I don't think so. Even when the technology gets to the point that power supplies are quiet enough so they don't require isolation in seperate boxes,I suspect preamps will endure because of the gadget aspect of another neat looking box on the rack and the commissions to the persons who sell them.

If we look onto many amps made today,
They already have a neccessary preamplification especially ones with differential input stages.
To have a few dB larger sencitivity may have an extra pre-drive stage.
In reality it's piece of cake to make from power amp an integrated one and build the volume controll after the drive or pre-drive stage so the issue with impedance matching will go away for good.
The minimalistic line preamps suchas McCormack TLC, RLD or Micro Line Drive will not become obsolete as they're just buffers with unity gain and extra inputs with input selector. To have integrated monoblocks is not so convenient anyway. They provide the minimal path for the signal interface.

Most volume controls in amps and CDP are of low quality volume control which really restrict dynamics and sound quality. If you are thinking going direct from source to amp, you need a very high quality volume control. I listen to vinyl only and I have a phono stage with a pair of transformer volume control (TVC) which is arguably the best kind of volume control. Some audiophiles use TVC in a passive box for their CDP. Most CDPs have digital volume control, which is the worst thing you can have. In any preamp, whether it's active or passive, volume control is extremely critcal, it could act as the bottle-neck for the whole system. TVC is expensive, but is really worth the money considering it control the sound level of your system, which could be many times the money of your volume control.

Aside from the discussion whether active, or passive, or no preamp can work better, may I mention another way to enhance signal transfer? Although I am a fan of the $350 EVS Ultimate Attenuators from tweakaudio.com, I have found that there is a way to improve passive or active preamp, or even no preamp (Ultimate Attenuators.)
Placing the SCE Harmonic Recovery System active box (no controls to adjust) between the CD source and the amplification seems to greatly enhance the CD listening experience.

"though passive pre's add nothing to the signal-they sound waayy tooo threadbare ..."

My experience does not support the statement above.
My cdp has a volume control, but I still prefer the Placette Passive linestage in the chain. The Placette replaced a $6k tube preamp in my system.

I think Bigkidz is right about the importance of matching and the quality of the volume control. These are two of the reasons the Placette performs so well.

Lots of good responses BUT it all depends on the matching of the CDP preamp and input on the amp. It also depends on the quality of the volume control in the CDP. The Shanling mentioned above had a poor volume control even in my highly modded one. It also depends on the preamp too. With some of the higher priced CDPs that have better volume controls, you will need a pretty good preamp to beat them running direct. I would not run an Audio Aero Cap MKII into many low end preamps an expect better sound than running it direct but maybe into higher preamps but this becomes a law of diminishing returns.

Oh come on Vvrinc, I mean, I'm a big vinyl fan and have listened to almost nothing but since returning to it 6 months ago (just bought a Plinius M14 phono stage here on A'gon). My kids think my turntable is cool too but they are still downloading their audiofiles (pun intended) and we must all acknowledge that vinyl is gradually fading away as very little new stuff is released and vinylphiles prefer to search for the dwindling stock of old .... but I don't want to derail my own thread from the basic question I asked (and thanks to many above for your perspectives). As noted, I need a preamp because I will alway have vinyl but can't ignore the reality of cd. I asked about the future of preamps because I'm concerned if I lay out some big bucks for one,(looking at an ARC LS16mk2), it won't be a good investment as many people are turning to alternatives. What is a good longer term investment for $2K used?

Forgive me, but, "vinyl wanes..."

I think the interest in vinyl and associated gear is greater now than it was before CDs came out. Even my kids, who were both born after 1980, are gaga over the 12-inch-spinners. For digital they are into that MP3 thingy but each has a turntable which they use when at home.

i agree with sugarbrie...

another reason for removing the pre is often a $$$ issue.

you cant get a decent new pre for less than $2500 to $3000 new or $1000-$1500 used.

though passive pre's add nothing to the signal-they sound waayy tooo threadbare for my taste and lack in dynamics /bloom/bass/and body

a interesting observation is there are alot more quality amp manufactures than pre-amp manufactures- ( most companies make a great amp but when it comes to preamps they suffer in comparison to the best pre-amp units such as...bat,audible illusions,Audio research(older ARC),pse hl-1, and cat)

Years ago pre-amps included tone contols. In the future they may include room controls. Multi-channel may expidite this.

More than 20 years ago I scapped the preamp in favor of an outboard phono section (PS Audio) fed into a Matrix multichannel decoder (Lafayette SQ W) which was probably the best matrix decoder ever. It provided source switching, gain, and volume control. Eventually I tried out a moving coil pickup, so I had to get a preamp for that.

Today I have a SS processor (Rotel 1066) and the old PS Audio phono section is back in action with a MM phono pickup, (rarely used).

So, in summary, I think that preamps are usually a bunch of unnecessary circuitry that the signal needs to go through. Less is more.

If we look a couple of decades back the preamp was only meant to be for RIAA phono preamplification.
The line sources such as tuners and tape decks were connected directly to the amplifier that is nowdays integrated ones.

There is the SCE Harmonic Recovery System, an active black box with no buttons or knobs, to place between the CD source, and the amp(s) which will improve the quality of signal transmission. It is much cheaper than any preamp, going used on Audiogon in the $250 range, and allows for those who prefer a direct connection, but feel that lack of preamp is failing to optimize the sound reproduction.
I use in each of my systems, both with, and without a preamp stage, and it improves the sound, as a good tweak should.

Even when comparing the sound of a stock Sony SACD player I find the sound more involving and dynamic when run through an active preamp such as my Aesthetix.

A while back I had both the Shanling and Lindemann CD players. I experimented with direct out (both transistor and tube buffer) on the Shanling, only to prefer using it’s output into my pre.

With the Lindemann, I ran it’s output into my Aesthetix Callisto and a top notch passive unit, with everyone preferring the sound of the active. This same experiment was performed a couple of years ago with a Sony SCD1 and a Levinson two piece unit with similar results. In all cases the added dynamics, control and bandwidth of the active pre (Aesthetix and / or Audio Research Ref 2 Mk 2) were the preferred combo over driving the amps directly.

Audiophiles will always have a pre-amp since they will laways use vinyl as their primary music source! : )

I listen to vinyl on a Linn LP12 and to digital on a TEAC VRDS T1 / Apogee DA1000E. My amps are Shanling SP-80 monoblocs with built-in electronic volume control. I could run CD playback straight to the amplifiers but I choose not to because there is an optimal amp volume setting ( -30dB ). So I put everything through the Klyne preamp and use its volume control, and feel I am getting the best that way.

So for me, running without a preamp is an option if you have only one source which is not vinyl, and if your volume control is excellent at all levels. For other systems, preamps will remain useful.

If you listen to vinyl you must have a preamp. Try hooking your turntable right up to the amp (LOL)!

I've never owned a preamp, and don't see one in my system any time soon.

With a few rare exceptions, intrernal volume controls are lacking in the bloom of analog. I do have a preamp fro you with built-in MM/MC phono. Check out my ad BVaudio P1

My preamp is the most important component in my system. It takes what is otherwise just sound and brings it to life..