[MirandaX]

Quote:

Originally posted by kelly Then comes pre-amps. Purposefully introducing into the path of my signal what could only be called distortion.

I think there's two realistic arguments for tube preamps:

First, the job of an active preamp is basically voltage gain. Tubes are very linear, more so than most transistors. Practically, this means that volume transitions in music sound really good with tubes. (Transitions from soft parts to loud parts are handled with finesse, and the midrange emerges nicely.)

Second, good tube designs tend to require less (or no) global feedback. MG Head owners can attest that flipping the feedback switch on deadens the sound perceptibly. Feedback makes a difference.

 

[Audio-Me]

backhands kelly's logical side of his bran.

 

[Tuberoller]

Kelly,

I understand fully the conflict which you are having.If this audio thing were logical, there would be no need for sites such as this.Before I was an electronics tech I never thought about why tubes "sounded" better,they just did.When I took the job at an electronics repair shop as a teen I was then completely confused.How in the hell could a tube amp ever concievabley sound even as good as a solid state?Transistor gear was sooooo much easier to dignose and repair(generally) and had so many fewer parts in the signal path.If it were not for my boss,Mr Ambrose,who always told me that "you never know what's gonna feel good".I always understood this to be an attempt to get me to go to a strip club with him or partonize his favorite hooker,It was later in life that I learned to apply that bit of "advice" to daily exploits.

You make some very valid points,especially the point about the introduction of "distortion" into a signal path.You seem to have a knowledge far beyond any "newbie".You logical side is usually wrong about things which appeal to your senses.There are things that taste good which when you think logically think about what you are eating should make your stomach turn,but you simply proceed to chomp away because it "tastes" good.I think the same thing applies to audio and tube signals.The distortion you describe is more pleasing to your sense of hearing,generally,than a solid state signal is.


I think your fears about tube gear reliability are perhaps based on your admitted bias but also a lack of exposure.Most tubed gear users will attest to the reliability of that gear.I will say that tubed gear is a lot easier for a DIYer to fix or "tweak" than solid state.When a tube goes bad it's easy enough to diagnose and replace,it's another nightmare when something else is wrong.On most solid state gear even a small problem usually requires a trip to the tech.

I have long since stopped trying to figure out why tubes in the preamp stage seem to have the most effect on the sonics of an audio signal.I am enjoying myself far too much.

 

[kelly]

Do most preamps have a direct pass button? So that you could easily AB mic and micout tubiness?

To be honest, even the concept of a preamp bothers that logical side of me. It's like, "So let me get this straight... you want to pay $700 for a noisy switchbox to purposefully stick between the source and the amp?"

 

[shivohum]

Quote:

To be honest, even the concept of a preamp bothers that logical side of me.

Kelly, from what little I know of electronics, I hear that preamps often make systems sound much better because they help match impedances. Often if you put the source directly to the amp (we're not talking headphone amps here) then the source will have a difficult driving the amp. I hear that this is why people who use passive preamplifiers or no preamps at all in inappropriate systems will hear a thin sound with few dynamics (though I have no experience of this myself).

By the way, impedance matching is also supposed to be the main benefit of the SCE Harmonic Recovery System.

 

[pigmode]

Quote:

Originally posted by shivohum Kelly, from what little I know of electronics, I hear that preamps often make systems sound much better because they help match impedances. Often if you put the source directly to the amp (we're not talking headphone amps here) then the source will have a difficult driving the amp. I hear that this is why people who use passive preamplifiers or no preamps at all in inappropriate systems will hear a thin sound with few dynamics (though I have no experience of this myself). By the way, impedance matching is also supposed to be the main benefit of the SCE Harmonic Recovery System.

After the Melos broke, I ran my AH! 4000 cdp direct for a few weeks. The Ah! has a higher than standard output (2.5+v) so vol. levels were not a problem. Once the LW-1 passive was added to the equation, I quickly realized that the direct connection was adding a harsh edge from the upper-mids through the highs.

A good active linestage does more than color (tubify, if you will) the sound--one of it's principle functions is to boost the signal so as to increase dynamic range. The main argument for the passve approach is transparency. Passive preamp compatibility factors include amp sensitivity, cdp output, and IC length.

 

[tbabb]

Since your on the topic of non-headphone tube amps, here is my $.02.

There are some great sounding Vintage stuff out there. Take for example this gem I found.

1959 EICO HF-81 ($350 from private seller)
Quad EL-84s
Tube Rectified
Point-to-Point wiring

These can be had for as little as $100 on ebay if you don't mind doing refurbishing yourself. It's unbelivable that a 1959 Vintage AMP sounds as good as it does.

I recently tried out a Manely Stingray Int Tube. About $2500 retail, and this little gem is every bit as clear, well defined soundstage, and with excellent bass and tremble extension.

More info and links

http://home.attbi.com/~tbabb/eico.html

- tb

 

[tbabb]

For those that are looking for tube kits, check out :

http://www.diyhifisupply.com/


Nice designs including Monoblocks, Integrated, and Pre-amps. Sweet prices too.


- tb

 

[Tuberoller]

While we are talkin' about old gear on the cheap,I picked up this gemhttp://www.imagestation.com/album/?id=4291937023 on ebay for $41.00.It works great and needed nothing but a power cord.I coud'nt believe I was the only bidder.this has an outstanding headamp and phonostage.I have been using it to power the Stax electrets posed on top of the amp,but I love the built in headamp.When I was a tech we dreaded seeing these come into the shop but soon figured out that they were way easy to fix.

 

[Trawlerman]

Am I alone in thinking that a nice system can be had by having a solid-state front end with tube amplification?


My current system consists:
Krell MD10/Studio DAC
Audiolab 8000Q Pre
2 x Tube Technology Genesis Monoblocks. Push Pull amplifiers with Gold Aero EL34 Output Tubes / Gold Aero ECC83 drivers. Running in AB Superlinear for around 100w max output.

driving Proac Response 1SC Miniature Monitors on Target R4 stands.




This system gives me all the smoothness of an all tube system yet doesn't have the fuzzy warmth that can sometimes invade the sound.
The 'take no prisoners' Krell/Audiolab frontend gives the drive/dynamics and sheer slam of an all solid-state system but without the slightly harsh sound that can sometimes goes hand-in-hand with them.

Best of both worlds? I like to think so. Whatever it is that I have, i'm certainly enjoying it

Warning! Gratuitous valve amp piccie

Sound As Ever

 

[Dusty Chalk]

No, I am one who believes that to really get the magic out of tubes, they need to be in the amplification stage.

And well done, not just "let's throw a tube somewhere in the signal path".

Perhaps the weekness in my system was the amplification stage, so just having a better one was the ticket.

But tuberoller knows what he's talking about, and I'm sure he has more experience than me, so I'm really just saying you gotta look at a lot of things. It might be a good rule of thumb, but if it's your only rule of thumb...well, just don't make it your only rule of thumb.

Just MHO based on what little experience I have.

 

[Trawlerman]

DustyChalk,

Just looked at your profile. I see you're using Spendor S3/5s.

I use a pair of Spendor SP3/1s along with a pair of Quad 77-10l's that were designed and manufactured by Spendor for the 77series from Quad in the mid/late-90s.

I can guess that they sound just sublime connected to a tube amp. My SP3/1s are pretty good on SS amps but turn into something else when fed by tubes. Must be something to do with their BBC heritage.




Sound As Ever

 

[pigmode]

Yeah, sometimes I think the most tube-sounding piece of equipment I have are my speakers (LS 3/5a). It also helps that Quicksilver amps have a rep for a strong tube sound, although the ones I have are a later SS rectified design that is supposed to trade off a little tube magic for increased dynamics.

 

[Tuberoller]

Hey KeVlaR and Dusty,

Great systems can be put together with a tube amp and solid state preamplification.In my experience however,I have found that the most cost and sonically effective means of achieving a tube signature is done in the preamp stage.I have a good friend who uses a Martin Logan Pre with a VTL tube amp and his system sounds very good.He had to do a lot of component swapping to acheive the synergy that makes this system shine,but listening to it makes his efforts seem well worthwhile.One combo I have never been able to get to work well is a passive pre and a tube amp.I recently borrowed an ASL passive and tried it with one of ASL's own amps and I was not impressed at all.This system never matched well with any loudspeaker I tried and I tried many.


I would say that component matching and careful auditioning is crucial when mixing transistors and tubes.there are some really aweful sounding systems out there that were put together without the essential component matching necessary with this type of system.I would add,that I think it is easier to match a tube pre with a solid state amp than vice versa.

 

[Dusty Chalk]

Quote:

Originally posted by KeVlaR Just looked at your profile. I see you're using Spendor S3/5s.

Yeah, but I'm also talking headphones (going from MF X-CANv2 to RKV). But yeah, could be. I think that (synergy) is more important than having tubes in the pre-amp vs. the power stage. MHO.