Atmasphere preamps are balanced and now have a remote option. Or maybe look into the Modwright 36.5
30 responses Add your response
If you are interested in trying the Veritas' with a SS pre, I can recommend the Wyred 4 Sound STP-PRE.
It has (2) xlr-outs, and (2) SE-outs....(2) xlr-in, and (3?) SE-ins
Works very well with Berkeley Audio Alpha Dac II > W4S SX-500 monos> Magnepan 1.7
...very transparent, low-noise, with a beautiful soundstage,
and a mid-range that is the best I have had with the Maggie 1.7...just overall good synergy with front>pre and amps
I have not tried a balanced tube-pre with this set-up, but will demo one someday, to see if I can get the same transparent, balanced, quiet background of the STP-Pre, with some of the vocal and mid-range magic of my tubed head-phone amp (Decware CS2+, with Senn650 and Beyer t-90 headphones....
Tried the Berkeley Dac 2 direct into the amps....Liked the W4S pre better....no loss(or no perceived loss) of resolution, and better soundstage and mid-range
I have limited experience with other combos, but thought this might be another option, and a good match for the Veritas'
good reviews on the STP-Pre also
If you're not absolutely set upon spending a lot of money, the Emotiva XSP-1 preamp is fully differentially balanced and comes with a nice remote control. It has received rave reviews from all who have tested/listened to it. And it comes with a 5-year warranty to boot!
You can view the unit and it's specs. here:
Owned a Balanced Audio Technology VK51se Preamp. All Balanced inputs AND outputs. No built in Phono stage however. Excellent sounding Preamp IMHO. All tube. One single chassis. You could probably snap one up here on A-gon for around 3 grand. And they are remote controlled as well. Very smooth sounding, unbelievable midrange texture and colors, solid bass performance. Audio Research is also a brand to seriously consider.
One reason for going with balanced operation is the effect that this has on the interconnects used, rather than just the fact that the amp might have a balanced input.
There is a standard for balanced operation that has been around for decades. It is there so that you can reliably and repeatably set up a system, with expectation for good results, regardless of the length or cost of the cables used.
IOW if the standard is used, the cables in the system cease to have significant effect on the sound of the system.
Here is the standard:
1) Pin 1 is ground. (pin 2 in the US is non-inverting, in Europe it is inverting)
2) The signal shall occur between pin 2 and pin 3 of the XLR. Ground is ignored!
3) The output impedance of the source shall be low enough that driving a low impedance can be done without change in frequency response or distortion. 'Low impedance' is typically less than 2Kohms.
If any of these rules are ignored (which is common-place in high end audio) the result is that the cable will express some artifact, and the length will be a problem. A common myth is that there is no advantage to short balanced runs; the truth is that balanced operation is lower noise even if the cable is only 6 inches long.
The take-away here is that if you can hear a difference with the cables in your system there is a problem. Its very likely that of two cables being compared, one might sound better than the other; the simple fact is that neither is entirely correct. It is the balanced standard that allowed the record labels to do the job that they did back in the late 50s (often known as the Golden Age of Stereo), when exotic high-buck cables did not exist.
The funny thing is that to drive the cable correctly such that its artifact is controlled and prevented is not difficult nor more expensive! The main thing seems to be education on the part of designers who very much seem to me to simply not know about the standard.
This is why I put up my prior post. Of all the preamps mentioned, how many can drive a 2000 ohm load without loss of bass or an audible increase in distortion or overall loss of volume? Its true that many amps have a high input impedance where this might seem to not come into play, but like I said earlier, if you ignore the standard then welcome to audible differences between cables, something the balanced line system is supposed to prevent. I am indeed saying that you need the low output impedance even if you are not driving a low impedance load.
... I am indeed saying that you need the low output impedance even if you are not driving a low impedance load...So true, you want the signal to drop across the load, not the preamplifiers output circuit. Its a simple voltage divider rule. The lower the amplifier's input impedance becomes, the more important the pre amplifiers output impedance becomes(need it to be LOW).
...It is the balanced standard that allowed the record labels to do the job that they did back in the late 50s (often known as the Golden Age of Stereo), when exotic high-buck cables did not exist... So true again. Listen to an old Peter Paul and Mary record, like the very first one, fantastic.
Atmasphere is 100% correct, except that most high buck cables are not really made right, just expensive.
I don't think you'll get true balanced circuits all the way through for 1K. Maybe a buffered input that is balanced, but it eventually goes unbalance into the overall gain strage. Why? It cost twice, or more, as much to be fully balanced all the way through. A cheater plug that uses just PIN 2 referenced to ground is common. This is done all the time to accommodate those with XLR's.
Something to look out for if not already mentioned is that you need to be careful with inexpensive preamp claiming to be balanced. As Rower mentioned, many companies will install an XLR connector on the back of their unit an say it has "Balanced Connections" when in fact, it is simply a single ended input through an XLR connector to accomodate those with balanced cables. It is no different than a single ended RCA connection.
If you find a preamp you are interested in that claims to have balanced connections (regardless of price), be sure to verify exactly what type of connections they are.
I also wanted to add to the discussion of output impedance. It is true that the lower the output impedance, the better a preamp will drive most solid state or low input impedance amplifiers. Our Purity Audio Design preamps have been paired with Audio Power Labs amplifiers at shows with an input of 600 ohms and MBL amps with 5k ohms.
Another thing to consider is the gain of the preamp. To high (or even to low) of an output gain and you will not be able to realize the full potential of your system.
In regard to the different sound of cables I think much of this has to do with their construction and material. All cable companies will make claims but in the end, it is your system and ears that will tell you what is best.
In regard to the different sound of cables I think much of this has to do with their construction and material.
With regard to balanced operation, the statement is mostly false. However it is widely believed by many in high end audio. "Mostly" as in: as long as the cable has an adequate shield with a twisted pair within for the signal, then other construction details and materials will be rendered moot.
However as I mentioned before if the standards of the balanced line system are *not* observed then the above-quoted statement is true.
I've got a VAC preamp that is transformer coupled on the output, and one can switch inputs b/t single ended and balanced (I assume also using transformers). I am told that this is a fully balanced preamp. Does that really qualify? It is fully balanced on the ins and the outs, but I think it must be converted to SE while within the preamp (I'm guessing that). The output impedence is very very low, which is good.
How does splitting the signal (or combining a balanced signal) with an Xformer affect the sound relative to having the preamp use 2 seperate paths all the way through?
Again - I don't KNOW that this is teh way the VAC works, but I think it is..............
Seadogs1, if the preamp is internally balanced, you should be able to get an output from the preamp by driving pin 2 and pin 1, and also by driving *pin 3* and pin 1 (pin 1 being ground). If it is unresponsive on one of those inputs, say pin 3 for example, then the preamp has the connector for convenience only.
The exception would be if the preamp employs and input transformer, but such use is rare in high end audio, although it would not surprise me in the least to see some products that use them. As a result, if in doubt check with the manufacturer.
With respect to cables, yes, its possible. A lot depends on the design of the transformers. If they are designed to be loaded with the relatively high input impedances that are common in amplifiers today, you will retain the Common Mode Rejection numbers but otherwise the construction of the cable will have a big difference on the sound.
The balanced line system is designed to eliminate cable artifacts! So some output transformers are designed to drive a low impedance (600 ohms being the standard). If the transformer is driving this impedance you insure that the cable is not influencing the sound at all.
Electrocompaniet makes a couple of preamps that are fully balanced and have standard or optional (fancy) remote controls.
I have always loved the EC sound - the punch of SS combined with the smoothness of tube. For some, the looks (perspex and gold) can be a turnoff, but they now make optional silver faceplates.
It recently discontinued a couple of models and released a new preamp, so there may be some demos for sale at dealers.
Certainly worth a listen.