[sikoniko]

let me correct my statement to say allow 2 channel balanced inputs.

[mariusconst]

Hi Marius,

No tuners planned.

james

Thanks James!
Marius

[James Tanner]

What do all of you feel a balanced input accomplishes from a performance standpoint?

james

[Bob Reynolds]

What do all of you feel a balanced input accomplishes from a performance standpoint?

james

Assuming the balanced input is implemented as a differential input, then common mode noise rejection is the typically cited advantage.

If you meant to ask about having balanced output on the CD player, then the reason I want it is so that I can run the signal into a balanced input on a preamp.

I currently use a Jensen output transformer to convert the unbalanced output of my Arcam FMJ CD23T player to balanced.

I will not buy a piece of gear that does not support balanced connections.

[James Tanner]

Hi Bob,

I guess I would like to know why you feel a balanced input on the preamp or a balanced output on the CD player is better than single ended other than the common-mode noise rejection. Or do you feel the common mode noise rejection in and of itself is a performance advantage?



james

[Phil A]

It could be better on long runs or if someone has RFI or EMI issues and I know people who live in the vicinity of broadcast towers and have real problems..  I can't imagine it making tons of difference in my particular situation.  I'm running balanced on all the channels of my SP1.7 into my 6BSST and 14BSST amps.  The 6B is a distance away (sits behind a couch) - perhaps just under 20 ft.  I make all my own interconnects so it is done for consistency.  The stuff I use for balanced or single ended is similar.  Since it is not a cost issue to me, if I have a choice, I'd go with balanced (obviosuly with a SP1.7 a balanced CD player is not an issue as it only has RCA ins) due to the potential for less problems and the fact the XLR is a better connection in my opinion than the RCA.

[Levi]

I hope this won't offend anyone.  I found this article from Balanced Audio Technology dot com website.  Please take this for our discussion purposes only.  Could it be marketing hype?  I have done A/B between unbalanced and fully balanced connection from input to output and I favored fully balanced connection.  I am sure a good RCA connection can be implemented but I preferred to be balanced.

What makes the balanced interface superior to a single-ended interface?

The superiority of the balanced interface comes from at least four areas:

   1. Connector quality. This one is probably the easiest to understand. Balanced XLR connectors use large diameter signal pins. They also are superior to the common RCA in that they provide a positive locking action. They incorporate properly designed strain relief as a feature. In the case of an RCA connector, the signal-carrying ground conductor also works as the strain relief - a situation far removed from ideal. Many of us have experienced broken RCA connectors when subjected to lateral forces - including the weight of some high-end interconnects. The high degree of mechanical and electrical integrity makes balanced XLR connectors the natural choice when signal integrity counts.

   2. Balanced interface noise immunity. When discussing different signal interfaces, it is important to evaluate their immunity to various noise sources. One group of these sources is represented by noise currents that flow between different chassis in a system (and between different parts of the same chassis, in fact). We shall call them ground noise sources. The second group includes various external sources that do not have a direct electrical connection to our system, but can affect it through their electromagnetic fields. Items commonly included in this category are various RF sources (radio stations, RF remote control transmitters, etc), magnetic fields (fields commonly found around large power transformers, power lines and home appliances), and electrostatic discharge events. Because of if its three-wire configuration, a balanced interface is substantially more immune to all of the above interference sources. By using balanced interconnects throughout our system, we, therefore, noticeably improve our signal integrity - our music signal is much less affected by extraneous noise.

   3. Internal power supply-gain stage interaction. It has been stated thousands of times before that the power supply has an enormous influence over the resulting sound of a product. With this in mind, we can take two different design approaches. One would be to put very high requirements on the power supply and then hope that it is up to the task. A second approach would be to simply minimize the demand on power supply performance from the start. Single-ended circuits put very high demands on the power supply's ability to keep up with signal-induced current fluctuations. Single-ended signals produce changes in gain stage current that must be accomodated in the power supply. Unless the power supply is capable of coping with large and fast current changes, it will constantly fall behind and the resulting sound will be degraded. Balanced circuits interface with their power supply in a "balanced" fashion. There are two gain stage currents present in the balanced circuit at any time. By the very nature of a balanced circuit, when signal appears at the input, these two currents will change in unison. One will increase, and the other one drop by the same amount. The resulting gain stage current change can be made almost infinitesimally small. In the ideal case, the power supply will not see ANY current fluctuation at all, and its job will become quite easy. This reduced demand not only makes power supply design far more efficient, it improves the performance of the power supply substantially.

   4. Many of us believe that symmetry is good. Balanced gain stages are inherently symmetrical. Little wonder then that many famous designers reached for balanced circuits long before the word "balanced" was used in high-end audio. As long as forty to fifty years ago, when all stereo components contained nothing but RCA connectors, many now classic designs were already completely balanced internally. To work with the RCA interface (the only one available at the time), one input of the balanced circuit was simply grounded. Why would designers use fully balanced internal circuits with RCA jacks for interfaces? The answer is that, even then, many designers believed in the inherent superiority of balanced designs.

Why should I consider buying a balanced component if I have a single-ended system?

There is a growing volume of evidence that a balanced interface offers superior sound quality. More and more companies are adapting it. The balanced interface is becoming the de facto standard for high-end electronics (witness the proliferation of XLR connections on digital converters, power amplifiers, etc.). Today, Balanced Audio Technology's equipment is perfectly compatible with your single-ended system and will most likely yield higher performance than a corresponding single-ended alternative. Tomorrow, if you add a balanced source, preamplifier or power amplifier, your system can take advantage of the benefits of fully balanced signal handling.

Can I easily hook up my single-ended components (i.e. ones with RCA jacks) to Balanced Audio Technology's electronics?

Yes. All Balanced Audio Technology products are designed to work flawlessly with any mix of balanced and single-ended components. Balanced Audio Technology manufactures custom high-quality balanced-to-single-ended adapters for just this purpose. Each adapter is made with a machined virgin Teflon mating shell that connects an XLR front half to a Teflon-insulated RCA jack. Just plug the adapter into the back-panel XLR connection on BAT electronics and you can use the high quality single-ended cable of your choice. No external active converter is required to make this connection. In addition, products such as our VK-3i, VK-20, VK-30, VK-40 and VK-D5 already offer RCA jacks on the back-panel for a direct connection to any single-ended component.

Is there going to be any performance degradation in using a mixed balanced/single-ended system?

No. All BAT electronics will work perfectly with any mix of components. However, moving to a fully balanced system will bring additional musical enjoyment.

I've heard that not all units that have XLR jacks are truly balanced components? Can you explain this?

Yes. There are many products on the market that add XLR connectors to an internal single-ended circuit. Such designs, while sporting XLR connectors, don't process the signal in balanced form. It is fair to call such units "pseudo-balanced". Unfortunately, this fact is usually not stated accurately in the company literature for these products.

What differences are heard when moving to a balanced system from a single-ended system?

We have conducted an extensive comparison of Balanced Audio Technology systems operating in both balanced and single-ended modes. The same external components were used as well as the same manufacturer's cables. Consistently, the balanced connection yielded a superior sense of air, more three-dimensional images, and a more clearly defined soundstage. The music was infused with greater life and energy.

[James Tanner]

Something else to consider is how the Balanced circuit is accomplished - Transformer, IC or Discrete circuits.

james

[Bob Reynolds]

Hi Bob,

I guess I would like to know why you feel a balanced input on the preamp or a balanced output on the CD player is better than single ended other than the common-mode noise rejection. Or do you feel the common mode noise rejection in and of itself is a performance advantage?

james

Hi James,

Yes, I do feel that the CMRR of a balance connection is a performance advantage. Doesn't the "pro audio" industry feel the same? All the pro gear seems to have either XLR or TRS connections. I assume there's a good reason for this.

Sonically, I much prefer running the 7B-SST balanced instead of unbalanced. In fact, switching from unbalanced to balanced has made me a convert. There is more ambient information and sense of air. I noticed the same effect after installing the Jensen output transformer on my CD player, though to a lesser degree.

I agree with the comment from the BAT literature that the XLR connector is superior to the RCA. It's really a shame that we've been stuck with the RCA connector in consumer electronics. Even though at audio frequencies it is not supposed to make a difference the impedance matching of a 110 ohm STP cable with an XLR connector should be an advantage.

Balanced cables are typically shielded whereas many "audiophile" unbalanced cables are not shielded. Why spend many many dollars on power conditioners, when the interconnection cables aren't shielded and act like antennas?

With the advent of home theater more folks are installing subwoofers into their systems. The subwoofer by necessity is typically a relatively long distance from the electronics. Running balanced connections to a sub can avoid the fairly common subwoofer hum problem.

-- Bob

[Bob Reynolds]

Something else to consider is how the Balanced circuit is accomplished - Transformer, IC or Discrete circuits.

james

Agreed. There seems to be two shcools of thought on how to best implement a balanced input: passive transformer or active circuit. The transformer school claims substantially better CMRR across the audio band compared to active circuits. They also claim that active circuits are much less expensive to implement. That would probably be the dual opamp IC solution James is referring to.

Supposedly this device addresses this issue:

http://www.thatcorp.com/1200desc.html

-- Bob

[James Tanner]

Hi Bob,

Yes I am familiar with THAT Corporation.

Transformers as you say have a very high CM rejection rate but they tend to suffer from overload at the bass end. IC's like THAT Corp are also very good at rejection but our test have found that IC's do not handle high voltage swings as well as discrete operational amplifiers.

james

[Bob Reynolds]

Hi James,

Like most engineering endeavers, various balanced input/output circuit designs have trade-offs. I certainly have no qualms with Bryston's implementation and I was sure that you guys researched the alternatives and selected an approach that you feel has the least downside.

It's Bryston's sound engineering approach and analog design expertise that has me waiting for their CD player before replacing my Arcam player.

-- Bob

[JeffMO]

I realize that you can't satisfy everyone, but I will miss HDCD decoding in the Bryston player.

Me too.  

I just hope it has XLR output to match with my BAT (Balanced Audio Technology) preamp.

Again, me too as I'm using a BAT VK-40 preamp.

[nicolasb]

I guess I would like to know why you feel a balanced input on the preamp or a balanced output on the CD player is better than single ended other than the common-mode noise rejection. Or do you feel the common mode noise rejection in and of itself is a performance advantage?

Are you suggesting that noise reduction is somehow undesirable?

(scratches head)

If you want another reason, how about the elimination of ground loops? It's a matter of isolation, really: single-ended connections use the same conductor both as part of the signal path (for the return of the current) and as the cable shielding; XLR connections have one conductor for the current return path and another separate one for the shielding. It makes sense to keep the whole of the signal circuit separate from, and inside, the shielding layer.

[James Tanner]

Hi nicolasb,

No as a matter of fact I and Bryston have been a big advocate of using balanced lines since our first products 40 years ago.

I was interested in the comments because I have had customers before indicate they used single ended because it was a more 'pure' connection.

Some feel that the 'sending' and 'receiving' circuitry required for Balanced lines in fact adds complexity (more electronic circuitry or transformers) to the signal path.

james

[nico75r6]

Hi James.

You said that you are an advocate of balanced connections. What is the reason they have not been implemented in the new B100 SST?

I have another question for you. Since you agreed high resolution format are a dead issue, why you want to implement SACD decoding in the new CDP? Don't you think this will affect the price or the quality in redbook reproduction?

Nicola

[James Tanner]

Hi Nicola,

We use Class A discrete Balanced circuits in our produts so the 'realestate' you need to impliment it is farly large. In an integrated where space is at a premium it is a bit more difficult to do.

With the integrateds the preamp and power amp are in the same chassis so the connections between them are hardwired so the adavantages of using long lengths of balanced cables in a system are not as much an issue of course. Also the cost of doing discrete circuits is part of the consideration.

As for balanced inputs,  if the Source is close - as they usually are - then  the advantages of common mode noise reduction by using balanced lines is not as important.

As for SACD we may rethink that. It is possible given the digital circuit we will be using so we felt we could offer it without a downside. We will see.

james


james

[brutbros]

I would like to strongly suggest that the new Bryston cd player include the ability to playback SACD.  I would be looking to replace my sony xa777es with a high-quality two-channel CD/Sacd unit (no need for a multi-channel sacd player anymore as I bought a universal player).  I became very excited when i heard in this thread that the new Bryston player would include Sacd.  This player is now at the top of my list to match my sp 1.7.  I would, however, only consider the Bryston if the player did indeed feature SACD playback.  While sony may have abandoned its baby, SACD is still the high resolution format of choice for many audiophile jazz and classical labels.

[nico75r6]

Thanks for your your answer James.

I asked about the reason you didn't put in the balanced connections in the B100 because the acclaimed Meridian G08 CDP sounds *** A LOT *** different when it is connected into a balanced input than with standard RCA.

I do not know the reason behind this but everyone tried it said it's like  listening to two different CDP. The G08 works a lot better with the balanced connections and I do not think this should happen.

I thought this could be with the Bryston CDP too so I was afraid not having balanced connections on my B100 SST I love so much. As signal cable I use standard Bryston RCA 1m cables.

Nicola

[James Tanner]

Hi Nicola,

That is a little strange that the Meridian would sound  that much different with the Balanced out. Balanced circuits typically add about 6dB of gain.

Is it possible the extra 6dB volume is 'seducing' the listener into thinking it is better?

james