[nickspicks]

I've spent a lot of time listening to various systems with and without preamps, tube preamp, SS preamps and Digital gain structures ala Benchmark DAC-1 or Grace units.

Currently, i'm running ICEpower based amps and a tube preamp in front.
its a combo that I could not live w/o.  and the right preamp just brings it all to life.  So much is missing without one.

Recently, i spent some time with a Modwright 9.0 beta and was blown away by what I was missing w/o this in my system.

I run a symphonies+, which after some tube rolling has come into its own, but feel that the tubes in the front w/the digital amp in the back is a very nice sounding combination.

[Sound]

Good  thread.  I would like to add the question of whether having an SS pre-amp with a tube amp is ok to do (good sound quality etc) or is it better to use a tube pre with tube amps.  Is anyone out there using SS with tube amps?

Thanks

[JLM]

Typically tube amps have low damping factors compared to solid state amps which affects bass reproduction.  The result is loose/bloated bass.  Some vendors counter by simply filtering out deep bass.  

Naturally low powered amps (most are the tube variety) lack sufficient power to reproduce the much more energy intensive bass compared to other frequencies.  This is another good reason to filter out bass response from small tube amps.

Before solid state the ideal pairing was tube amps with (high efficiency) horn loaded speakers with compression drivers.  To do deep bass horns get very big (garage sized) so they just lived without, which suited the poor bass output of those little tube amps just fine.  Nowadays you can add a separate subwoofer powered by a solid state amp to handle the bottom 1 to 3 octaves to do the heavy lifting.

[nickspicks]

or you can buy Manley products.


w/the tube amp, personaly..I liked the "no preamp" option of a benchmark in front.

[Sound]

Tell me more about the Benchmark- I assume it's a DAC with volume control?  So I take a CD player and connect the DAC to it and use the DAC as a pre-amp?   If that's correct, is there as much slam as with a pre-amp? What I don't want is the SS front end to compromise the Tube sound in the rear.  

Also, my speakers have a built in ss amp for bass, so the tube amps work great with it.  Just trying to find more slam.  Currently I am using an old Sony NS555xe with volume control.  Sound is a bit dark, nice sound stage but I notice in very complicated string orchestra music things start to become smeared together and I am looking for that to open up and be more detailed.  I have also found I am listening at very loud levels to get more slam and I would like to find that in the system rather than in the volume.

Don't want to take over the thread but I think this does relate to the Pr-amp/no pre-amp question originaly posted.  Anyone with thoughts/recommendations would be appriciated.

Thanks

[nickspicks]

I thought it was pretty slammy.  
but there is no replacement for a world class preamp in any system, imo.

w/the benchmark, we were running that (yes, dac w/volume) directly feeding  a BAT vk60 amp.  the benchmark has balanced output, which is perfect.
IMO, while there was some punch, the BATT could not produce the volumes we  wanted for rock-n-roll stuff and it tended to strain a bit.  
I always thought there was something bright sounding.  it could have been the DAC or it could have been cables.  who knows.  at the time, we didn't have a preamp to play with.

now, we (my friend and I who share gear) have several preamps, the benchmark and a DAC60 to swap around.  He  is now running Monarchy 100's and i'm running a custome ICEpower setup and we both have tube preamps.  the DAC doesn't do much, but still sounds super sweet.

if slam is what you are after, then the Grace 902 is the one.  that is a DAC/headphone amp w/unbalaned output AND...a remote.  which is the clincher.  It is way more "solid" sounding than the Benchmark.  both are awesome units, but he Grace has some tight PUNCH that the benchmark does not have.

[avta]

Hello all:
I'm inclined to agree that the combination of a tubed pre and a ss amp offers sound that is superior to what I've heard in my system and a few others. I'm running an old Pass Aleph3 which is a pure class A amp., Norh aca 2b tubed pre and Magnepan 1.6's. I use computer based input from Exact Audio Copy and keep the flac files in an external drive. The sound quality is quite good considering the modest cost.

Guy

[nickspicks]

is there anything finer than "quite good for modest cost"
that is my goal, at all times.


i've got barely a grand into my system (speakers and cables not included) and its the best sounding setup i've had.  and i've spent 5x that much on seperates in the past.

[JLM]

Note that some power amps are basically composed of two gain sections, so in effect they are integrated amps without switching, tone, or volume controls/options.

Manufacturers like Channel Island Audio offer passive pre-amps so they design amps with high gain (32 dB) versus the more typical 20 or 26 dB of gain.

[tanchiro58]

If you are interested in tube preamp I will introduce you to the brand new company, who build a tube preamp using one rectifier tube like 5U4 or U52 and two output 8233 tubes through two interstage transformers. This preamp has a lot of gain(36dB). It drives my monoblocs 300B with plenty of low bass, the 300B amps drive a pair of Von Schweikert VR1s + Hsu 10" sub.

[Steve]

Every audio system needs a certain amount of gain. This can be accomplished three different ways.

1) The CD player's op amp, acting like the preamplifier. Some have tube stages instead of an op amp.

2) The typical preamp is simply incorporated into the amplifier, called an integrated amp.

3) CD player, preamplifier, and basic amplifier

Notice all three actually have a preamplifier in the system. It is just a matter of where. However, each has it's own strengths and shortcomings.

I agree with nick and others that a tube pre does magic.

Hope this helps.

[jaspal kallar]

Yeah I definitely prefer an active preamp over the passives. Especially a tubed preamp. I've tried several class D amplifiers or regular ones with a tubed preamp. It just fleshs out more tone from the music IMHO.

All the passives I've heard sound flat when compared to a good tubed preamp.
I just can't get away from the presence of a decent tubed preamp. Too my ears it is more musically enjoyable. I've yet to hear any SS component that could take the place of what tubes are known for. I like the control of SS..this is why I prefer to use them as amplifiers in a system and let the tubed preamp supply the tone and body to the music.

 IMHO it's a compromise between two components to get the sound you want. You can't tweak a passive or SS preamp to your liking. ..What you hear is what you get. You can with a tubed preamp..just by changing tubes.

Hi,

I know you have a new "toy" (a TVC pre-amp). So has your opinion changed in any way?

  - jaspal.

[GHM]

Yeah I definitely prefer an active preamp over the passives. Especially a tubed preamp. I've tried several class D amplifiers or regular ones with a tubed preamp. It just fleshs out more tone from the music IMHO.

All the passives I've heard sound flat when compared to a good tubed preamp.
I just can't get away from the presence of a decent tubed preamp. Too my ears it is more musically enjoyable. I've yet to hear any SS component that could take the place of what tubes are known for. I like the control of SS..this is why I prefer to use them as amplifiers in a system and let the tubed preamp supply the tone and body to the music.

 IMHO it's a compromise between two components to get the sound you want. You can't tweak a passive or SS preamp to your liking. ..What you hear is what you get. You can with a tubed preamp..just by changing tubes.

Hi,

I know you have a new "toy" (a TVC pre-amp). So has your opinion changed in any way?

  - jaspal.

Yes for sure!! I still like actives but I truly enjoy the TVC. I hadn't heard a TVC when I posted those comments. You know how it goes with audio..It is a constant learning curve. I know now a passive can have great sound if setup properly.

Good listening

[TONEPUB]

What has always determined the active/passive question for me has been the source component(s).
I have a C-J CA200 in my living room which has a passive front end and with some gear it sounds
quite good, but due to buffering and impedance issues (partly from cables...) some components sound very lifeless.

Always best to experiment if you can!

I have reviewed quite a few components with this combination as an option, but my main system uses a tube preamp as well...

[Zero One]

Initially I ran my system which consists of gainclones (quite different from most around in many ways) and high efficiency full range speakers without a pre and I was pretty happy, but then I built one of these ( http://www.altronics.com.au/index.asp?area=item&id=K5502 ) with its associated power supply and about 25 mods.

Bottom line the system sound substantially better with the pre than without, lower levels of distortion (none) far better treble and very nice bass.

Recently is removed the pre to build it into its final case and had a listen out of curiosity, which just served to reaffirm my first impressions.

So by my reckoning the pre is a good thing, and this one by the way can be bought as a full kit, case and all, here is the link

http://www.altronics.com.au/index.asp?area=item&id=K5500

There are a few of these built now and I have yet to hear a complaint.

[Imperial]

Not using an active gainstage BEFORE the poweramp is something I believe ultimately will rob the
music of some dynamic resolution.
It also puts extra strain on your source.

Considering the size of the powersupply on some preamps., and then thinking we can do without this in
the source-amp connection?
Its all an enigma you say? Well I believe it to be VERY STRANGE that not more sources AT LEAST have
the same size powersupply then as do some really good pre-amps... Then I would consider believing one
could do without the pre as a separate component...

I have yet to see a source components powersupplies approach most of the good preamps units...
I cant think of a single one actually, that really outdoes a preamp there... not a worldclass one anyway.

So I conclude that, really, we don't need active pre? Hike up the capacity in the source, and I'll consider becoming a believer...

Imperial

[ctviggen]

Well, the Proceed CDP's power supply is easily the equal of the Proceed Pre's power supply.  Now, whether these are "world class" or not, I don't know.  Plus, the size of the power supply has little, if any, correlation with the quality of the output.  A preamp's power supply is larger simply because it has more stuff to run.  A CDP (or a squeeze box) has fewer components and therefore needs a smaller power supply.  Judging quality of a preamp function (in a CDP/SB/Preamp/whatever) by the size of the power supply is not necessarily a good thing to do.  One could build an incredibly large, but very poor power supply.

[Imperial]

Well that is so.
There are some fine examples on the DAC/Pre combomachine market that has some real good results.
But, I still think that the powersupply issue will set things apart.

On a certain level, as you do mention, some sources will have an ample supply for the signal to ride on.
But as a rule of thumb... most sources do not have the powersupply that does make a preamp in most cases, a good addition to the signal chain.

Now, the actual physical size may vary on powersupplies, yes that is a point to be taken, granted.
But few sources will have a supply that is better than a preamp, say of equal price.

It may come down to personal liking, how one likes it to sound.
Some reviewers do go on quests for the shortest chain of components, and really do try to find a
source that will allow them to run sans preamp.

The best example I've read about so far must be the  Aurum Acoustics Integris CDP.
So there are maybe stuff out there that do give the pure preamp a run for the money that they may loose. I believe that Stello has a few good componets in this approximation as well, and in a More achievable pricerange for the consumer that wishes to do without a preamp.
Stello not being the only contender, of course. Lavry does have that little DA10, that also does have
volume ability, albeit the ergonomics being rather incredudible do-dippety to operate...
Its a very svelte component, but is sort of cheap, and will function well in a system without a preamp present, yes...

-----------------------------------
Sidestepping the issue slightly here...
I also think it is worth mentioning the issue of noise.
System synergy. What I mean by this is to know from whence the noise cometh.
Source should have a low to normal output, say 1,0 to 1,7volts.
The preamp should really be a goosemachine, giving out up to 12 volts P-P.
The poweramp should then be of the (needs 4 to 5 volts to achieve maximum output) variant.
This I believe to be of greater concern than the issue of preamp...
In many cases you just keep amplifying noise until your speakers sing the song of "The iceman cometh" and adds chills to yer sound...
---------------------------------------------------------------
I also like to put a tube in the chain somewhere. I must have my glow!

Imperial

[Imperial]

It is also worth mentioning that we do have an evolving industry.
That is also the fact with the reviewing industry.
When I started reading about audio components ca 1985-86 I believe it was, the
buzz was much more on integrating stuff into one box.
Then came the separate box solution.
Preamps and monoblocks and separate dacs and all started popping up into the 90's.

When Mark levinson released the 383, it all started to go backwards again...
Rowland also could be mentioned here. and B&O.

Its about trends really, and the evolution of the powersupply, and the advent of frontier technology.
The buzz these days is about the shortest signalpath, when IMHO it should be about grounding issues
and getting the groundingplanes to work for the best.

We have access these days to smaller and smaller components, IE buildingblocks of our gear.
The SMD approach is more and more accessible to the industry now, and the impact is felt, and seen on
the size of stuff that reproduce our main interest, music!!!
So really , I'm just waiting for the 3D SMD circuit. It does exist in some high-end gear already.
The Lyra Connoisseur 4.2 and the likes, they assemble gainstages in small "pods" that connect in 3D to the rest of the circuit.

This I believe is the way to go also for the circuitboards. Flat is out! 3D assembly is the new hype.
Today its, do we need the preamp?
Tomorrow it will be: Do we need the cable?
Its coming. You can bet your Lilly asses it is...  aa

Imperial

[audiosapiens]

You need a high-end tube preamplifier. You can make your own or you can buy one.


________________
Madisound Catalog by Speaker Components  -  Get the Madisound Catalog by Speaker Components, Inc.