Tubes - where in the chain is best?

OK, so I'm back into the world of audio, and enjoying it immensely thus far!

I've retired my Polk RTA 12's and replaced them with a pair of Vantages and a Descent i sub! Holy smokes, I never heard half of what I'm hearing on my CD's now and I'm still using my old 100 watt Hafler DH200 power amp with my Hafler DH-110 preamp, and it doesn't sound all that bad! I also bought an Oppo DV 981-HD for DVD watching. What started this transition was when I "won" a 46" Samsung TV! The rest of the system, including CD player and cables are, well . . . . junk!

I have soooo many questions I really haven't a clue where to start. I have enjoyed searching through the posts on this site for ideas . . . BAT, Cary, Classe, Sunfire, Cardas, Nordos, PS Audio . . . it's endless! So many choices, so little time . . . and money.

Anyway, enough of that. Here's my first question. I have never listened to any tubed equipment, but the idea fascinates me. From a logical standpoint, I have a hard time seeing where having tubes in every piece (power amp, pre amp, CD player) makes much sense. Isn't that over kill? (I don't want to offend any total tube folks, should there be many out there.)

If you had to pick one piece of equipment to add tubes to your system, where would it be and why? I vote for the pre amp, but hey, what do I know, I've never even listened to a tube piece!!!!

I'll sit back and wait for discussion. Thanks in advance!

I'm not a tube guy but just for comparison:

Until about six months ago, I used DH500 for my main amp. I now have a Musical Fidelity A5 Integrated amp (solid state). It is an improvement

In this same series, Musical Fidelity puts tubes in the output stage of their CD player, and feeds that to the SS amp. This configuration is what my audio store used to demo the Ascents back when I got them, and now use to demo Vantages. The Summits are in a different room powered by about $30k of Classe stuff.

Without doubt, a tube preamp is the way to go. I have an Audio Research LS25 MkII driving a s/s power amp. The preamp is deathly quiet, even with my ears right up against the Summit panel. There are plenty of switching options including the all important HT bypass. So while my system is orientated for 2 channel listening, at the flick of a switch on my preamp, I can enable my low cost surround receiver and DVD player (Pioneer brand) and voila - HT sound!

Advantages of a tube preamp include lower running costs and the ability to select a high power s/s power amp to drive my Summits. I saved more money by buying my preamp new and my first power amp used. I currently have a brand new Mark Levinson power amp, but that's another story...

edwinr said:

Without doubt, a tube preamp is the way to go. I have an Audio Research LS25 MkII driving a s/s power amp. The preamp is deathly quiet, even with my ears right up against the Summit panel. There are plenty of switching options including the all important HT bypass. So while my system is orientated for 2 channel listening, at the flick of a switch on my preamp, I can enable my low cost surround receiver and DVD player (Pioneer brand) and viola - HT sound!

Advantages of a tube preamp include lower running costs and the ability to select a high power s/s power amp to drive my Summits. I saved more money by buying my preamp new and my first power amp used. I currently have a brand new Mark Levinson power amp, but that's another story...

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I agree. I have a CAT Ultimate and an ARC REF2, both driving Krell PA's. With top notch performance from both the combinations. Both dead quiet (from this point of view the CAT made great improvements compared to the early versions, even if it lose some of the "tubey" warmth).

greetz,
Fabio

Read my review of the

McIntosh MC275 on the Recommended Components forum (just amps for now). It's also become the choice of many Vantage and Summit owners (the ones who've discovered that ESL panels by themselves, do very nicely with a 100W amp.)

IMO, the amp (and speaker, of course) are most responsible for the sonic character of a system. The speaker for obvious reasons, and the amp because it's where the signal undergoes the most "processing", in the 'gain stages' where its strength is increased many fold and any attributes added or subtracted by the equipment are magnified.

Not to diminish the importance of the preamp -- a bad one can destroy an otherwise excellent system, but what distinguishes all the good ones is that they just disappear

Definately a tube preamp is the place to start. There are alot of reasonably priced, reliable and wonderful sounding products out there. Once you hear tubes in your system there is no going back.

Speaking of quiet, or should I say noise, the demo pair of Vantages that I had in my home until my current Vantages showed up, BOTH have a low wowowowowow noise coming from the 8" woofer. It is very noticable to me when the system is in "sleep mode", so much so that I have to unplug them if I am laying on the couch in front of them beacuse it irritates me.

Is this the way it is with Vantages/Summits? I'll have to check next time I'm at my dealer.

By the way, I have to return the Vantages after about 25 hours on them for a replacement pair. Believe it or not one of the panels goes out if it's touched or torqued ever so lightly. The sound comes back on as soon as you let it go. I have seen people move these speakers around by the panel without a hitch. Of course I am not doing that now, but moving them from the base, which on carpet is a challenge. That's another topic all together.

"IMO, the amp (and speaker, of course) are most responsible for the sonic character of a system. The speaker for obvious reasons, and the amp because it's where the signal undergoes the most "processing", in the 'gain stages' where its strength is increased many fold and any attributes added or subtracted by the equipment are magnified".

I'm confused here. This is why I thought the pre amp may be the most important in the chain, more so then the power amp, since the power amp, assuming it's doing its job correctly, is magniying what the pre amp is sending it. So if the pre amp is not up to speed, the power amp is just magifying a bad sound.

Either way, it seems that thus far the vote is for a SS power amp and a tubed pre amp. Sound right? No pun intended.

PS: I'm still testing how to make these posts, so please hang in there until I figure it out.

If you've never listened to valve electronics then you should start! You might not even like them!

A valve preamp is certainly a less heavy-handed approach - valve preamp into a solid state amp is what I use - i'm running a Copland CTA-305 into a Classé CA-101.

I've found that a valve amp will give you more of that valve character, but with quite a few drawbacks as well. A valve preamp will give a little less of that valve magic, but without (or much less anyway) the drawbacks.

music again said:

"IMO, the amp (and speaker, of course) are most responsible for the sonic character of a system. The speaker for obvious reasons, and the amp because it's where the signal undergoes the most "processing", in the 'gain stages' where its strength is increased many fold and any attributes added or subtracted by the equipment are magnified".

I'm confused here. This is why I thought the pre amp may be the most important in the chain, more so then the power amp, since the power amp, assuming it's doing its job correctly, is magniying what the pre amp is sending it. So if the pre amp is not up to speed, the power amp is just magifying a bad sound.

Either way, it seems that thus far the vote is for a SS power amp and a tubed pre amp. Sound right? No pun intended.

PS: I'm still testing how to make these posts, so please hang in there until I figure it out.

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I concur. My observations and discussions with many other enthusiasts is that the pre-amp holds the key to unlocking the magic within your system. IMO, next to the speakers and quality of the recording/source, the pre-amp will make a bigger impact than the amp. However, I don't want to make a lot of broad and sweeping statements. Surely, a good amp can improve the experience dramatically and a poorly designed amp can give you all kinds of headaches, especially if you are driving electrostatic speakers.

Make no mistake, the pre-amp counts. When I was at Richard's (dreamer's) house we compared his home-built, passive pre-amp, to his other unit (can't remember what he had at the time and he uses a Krell now) but the 'cheapo/ghetto' passive pre-amp actually sounded very good compared to his SS counterpart.

Erik

music again said:

OK, so I'm back into the world of audio, and enjoying it immensely thus far!

I've retired my Polk RTA 12's and replaced them with a pair of Vantages and a Descent i sub! Holy smokes, I never heard half of what I'm hearing on my CD's now and I'm still using my old 100 watt Hafler DH200 power amp with my Hafler DH-110 preamp, and it doesn't sound all that bad! I also bought an Oppo DV 981-HD for DVD watching. What started this transition was when I "won" a 46" Samsung TV! The rest of the system, including CD player and cables are, well . . . . junk!

I have soooo many questions I really haven't a clue where to start. I have enjoyed searching through the posts on this site for ideas . . . BAT, Cary, Classe, Sunfire, Cardas, Nordos, PS Audio . . . it's endless! So many choices, so little time . . . and money.

Anyway, enough of that. Here's my first question. I have never listened to any tubed equipment, but the idea fascinates me. From a logical standpoint, I have a hard time seeing where having tubes in every piece (power amp, pre amp, CD player) makes much sense. Isn't that over kill? (I don't want to offend any total tube folks, should there be many out there.)

If you had to pick one piece of equipment to add tubes to your system, where would it be and why? I vote for the pre amp, but hey, what do I know, I've never even listened to a tube piece!!!!

I'll sit back and wait for discussion. Thanks in advance!

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To answer some of questions:

No, I don't know anyone that injects tubes all over the place. Most of the big companies that make high end CD players, don't have many that include a tube output stage. Some companies make tube buffers and other, smaller, outfits modify CD players so they have tubes at the output stage.

Most folks use tube pre-amps, or maybe tube amps. In general, tube stuff is pricey and the tubes need to be replaced every now and again (that isn't cheap). If you put a lot of hours on your system and use it for HT, all tube equipment may not be the way to go.

That said, I am sure there are some individuals that have tubes up the wazoo. But if you have never listened to equipment that contains tubes, you might want to start out 'small' and go with a nice tube pre-amp and see if you like it. Naturally you can A/B a good SS pre-amp against a nice tube pre-amp and see if there's a big difference.

IMO, the type of music you listen to makes a bit of difference here. If you like Rock and Pop music, some say that the tube equipment lacks 'punch.' However, if Jazz, Classical, or songs with lots of mid-range vocals (Krall, Barber) etc, then tubes might be the way to go. But, again, it's all very subjective.

The earlier in the signal chain the better, IMO. A tube pre amp will give around 70% of that tube magic but to get the remaining 30% you'll need a tube amp also. I am totally resold on tube amps as I was a SS amp guy for 15 years or so until a return to tubes 2-3 years ago. I recently added a tube DAC and am looking for a tube phono stage to finish off my electronics for a long time. Speakers are the final element, maybe Quad 2805s or 2905s.

Lots of people think the preamp

music again said:

"IMO, the amp (and speaker, of course) are most responsible for the sonic character of a system. The speaker for obvious reasons, and the amp because it's where the signal undergoes the most "processing", in the 'gain stages' where its strength is increased many fold and any attributes added or subtracted by the equipment are magnified".

I'm confused here. This is why I thought the pre amp may be the most important in the chain, more so then the power amp, since the power amp, assuming it's doing its job correctly, is magniying what the pre amp is sending it. So if the pre amp is not up to speed, the power amp is just magifying a bad sound.

Click to expand...

is the heart of a system, but as I said, if it's doing its job, a preamp should just disappear sonically. The preamp is basically a traffic director, switching between sources. It also provides recording outputs, but unless it has tone controls or a phonostage, it's not doing any signal processing per se. And precious little amplifying, other than to configure (impedance-wise) the signal to drive the amp's input impedance and driver stages. That is the reason for the popularity of the "linestage" preamp among purists, often not even powered, just a selector switch and an attenuator.

The amp on the other hand boosts the signal's strength by (typically) handing it off back and forth between pairs of power transistors or power tubes, each time re-copying the signal (so to speak) at a higher power. How faithfully the signal is preserved at each one of these re-copying (gain) stages determines what comes out the other end.

It's at the instant when a pair of power tubes or transistors hand the signal back and forth that all the weirdness or goodness happens. Transistors turn on and off very fast, and if their push/pull circuit(s) are not carefully designed, some of the signal (particularly low level and harmonic information) can literally get lost in that crack, leading to what some perceive as a kind of hardness or glare. Tubes turn on and off (comparatively) slowly. There's some overlap. So no chance for anything to get lost, however, if they do it too slowly (and if they don't couple properly to a distortion free output transformer) you get a bloated, schmaltzy sound that some people find pleasant (not true of all tube amps, and certainly not mine!)

But make no mistake, amps and speakers are where it's at, and the notion that it's possible to warm up a SS amp by placing a clean, quiet tube preamp ahead of it is pure, unadulterated bullpucky, in my ever-so-humble opinion :bowdown:

I want to thank everyone for their input thus far. I am all EARS!
It's back to the drawing board on my thoughts about tube power amp or pre amp. The good news is that I can spend thousands of dollars in my head thinking about what to do, without actually handing over my credit card to anyone!

My local ML dealer carries a lot of the names I keep seeing on these threads, such as Krell, Rotel, Sunfire, BAT, Cary Audio, Classe', Conrad Johnson, Kimber Kable, MIT, Panamax, TARA labs, and more. If I can't find a system from that list, something's wrong. Off course a lot of these brands are EXPENSIVE for sure. Right now, just getting my wife to agree to the Vantages and a Descent i was a major miracle! My goal for starters was to get the best "front end" I could afford and from what I hear, I think I made the right choice. Although HT is a consideration for the future, I listen to music 90% of the time. A little of everything really, from rock (SRV) and contemporary to jazz (love Jean-Luc Ponty) and classical and whatever you clasify Santana as.

I may start a new thread on suggestions for a logical future upgrade path. Right now I'm just enjoying the HUGE difference I'm experiencing just retiring the Polks and moving onto the ML's. What a difference! My wife even appreciates the difference, which may make it easier to upgrade. She could never listen to female vocals because of the top end. The ML's are so smooth and natural. I keep telling her she hasn't heard anything yet!

Thanks again!

edwinr said:

There are plenty of switching options including the all important HT bypass. So while my system is orientated for 2 channel listening, at the flick of a switch on my preamp, I can enable my low cost surround receiver and DVD player (Pioneer brand) and voila - HT sound!
.

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Newbie question here, but I too am looking at tube pre-amp. Can you explain how the HT bypass works? How do you connect it in your system? I assume you have a separate CD player connected to your preamp for 2ch music? Thanks

Preamp in my opinion.

I, too, am using a tube Pre (Modwright SWL 9.0SE), which has the Home Theater Bypass (HTB).

For pure two channel listening, I feed my source (CD player or Squeezebox into a Benchmark DAC-1) to the Modwright (HTB switched off) then to my Belles amp.

For home theater, my DVD player feeds an older Yamaha RX-V1000 receiver, which directly powers my center and (in-ceiling) surrounds, and also feeds an NHT Sub Two. I have the Yamaha Main (front) pre-outs going to my Modwright/Belles powered Summits. Thus, for watching DVD's, the Yamaha handles all the video and DSP processing, and is the SOLE volume control. With the HTB switch on, the Modwright volume control is inactive, and merely passes the front speaker signals thru to the Belles/Summits.

Another point to consider, especially if you watch a lot of DVD's, is whether the pre-amp HTB functions even when the pre-amp is turned off. The Modwright must be ON for the HTB to work, theoretically "burning" the vacuum tubes needlessly while watching video. I *think* some other Pre's leave the HTB active by default, even when powered off. That could theoretically prolong the life of the Pre's tubes, and also make it simpler for non-techies (e.g. wife, kids) to watch video when you aren't there.

sleepysurf said:

Another point to consider, especially if you watch a lot of DVD's, is whether the pre-amp HTB functions even when the pre-amp is turned off.

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So there is just a set or multiple sets of inputs on the back of the preamp that are for use with the HTB mode? Excellent point! I would watch a lot of DVD's or even just TV and there is no need for a fancy tube pre to be running for that. Also a good point for simplicity sake. Does anyone know of some Brands/Models that default to the HTB on when powered off? Sorry for getting off topic here.

+1 on being interested in a good tube preamp that has HTB w/o running the tubes. This sounds like a great way for me to sneak into the wonderful world of tubes. 98% of my listening is 2 channel and I may only watch one or two movies in an entire year! The rest of the time my wife is using it to watch soaps uke: What a waste of tubes that would be :duh:

It's so easy now to find a receiver with a jillion plugs on it for all the kids video games and whatever other sources I need but really the only one that matters to me is the two cables coming out of my CD player. So... to be the perfect preamp (IMO) it would need to have at least one set of XLR inputs, XLR outputs, and this 'passive' home theater bypass. Any of you know of said piece?

Thanks!!!

Preamp

I also favor tubes in the preamp !