Burson Audio Buffer

Roger A. Modjeski · « **on:** 14 Nov 2007, 04:57 am »

Does anyone have or want or care to hear my opinion on this $300 device? Here's the link.

http://www.bursonaudio.com/Burson_Audio_Buffer.htm

There are serious flaws in his understanding of electronics.

ooheadsoo · « **Reply #1 on:** 14 Nov 2007, 05:23 am »

Yes, please.

jules · « **Reply #2 on:** 14 Nov 2007, 05:54 am »

Hmmm ... not sure on this one. If you're talking about a review of the product based on listening to it ... great. On the other hand, if you're talking about a critique of the designers ability to communicate what his product does, in their absence ... maybe not fair

jules

jeffreybehr · « **Reply #3 on:** 14 Nov 2007, 06:00 am »

Seems to me the intelligence and CARE of this person is exemplified by these obvious errors:
"... intergraded amp..."
"...between all component and..."
"We use only the best match component and..."

Doesn't he/she READ his/her own stuff?

And the implication that some of the line-level Voltage is 'wasted' by impedance mismatching at audio frequencies is laughable. My my...

Roger A. Modjeski · « **Reply #4 on:** 14 Nov 2007, 06:17 am »

Jules,

Does your response mean that you have one and like it?

To All reading this topic:

What I find interesting is that the premise of his product is to aid in impedance matching, yet it doesn't appear to do that at all. In fact, he argues for lower output impedances yet the examples he provides are all very low to start with. His examples show that different units from the same or different manufactures have different impedances and this is not a problem at all. I find it interesting that with all the talk about impedances he does not state either his input or output impedance.

In the little box to the right marked Technical Fact, he defined "Impedance Matching" yet he is not doing this at all. In most systems the output impedance of the source is very low (0 to 1K ohms) and the input impedance that it is driving is quite high (50 to 500K ohms). Those are far from equal.

Jeffrey,

Thanks for your eagle eye in proof reading. Both the article and the picture of the dripping RCA connectors do seem to imply that.

DSK · « **Reply #5 on:** 14 Nov 2007, 08:27 am »

That was why I started this topic ... http://www.audiocircle.com/index.php?topic=46765.0

I have no EE knowledge at all and was struggling to convince myself that it would be advantageous to add it to my system. In the end, because it was so cheap, had received favourable comments from modded SB owners, and had a 30 day risk free period, I decided to just go ahead and listen for myself.

I still don't really understand what it does or whether it really is impedance related or current & voltage swing related, or .... but it certainly did provide improvements in my system, despite going against my sensibilities by adding another component and pair of IC's in the signal path.

jman66 · « **Reply #6 on:** 15 Nov 2007, 02:52 pm »

DSK

Keep in mind that if you're using the volume control in the Squeezebox, it's one that is implemented in the digital domain. With the SB connected to a preamp, the volume of the SB should be set to max to ensure no bits are being lost.

sts9fan · « **Reply #7 on:** 15 Nov 2007, 03:15 pm »

I am borrowing one of these jobbies right now. I have yet to give it a good listen though. I am skeptical mainly because I don't want to add another link to the chain? I also think it may be added to some products just to increase the price.

DSK · « **Reply #8 on:** 15 Nov 2007, 09:07 pm »

Quote from: jman66 on 15 Nov 2007, 02:52 pm

DSK

Keep in mind that if you're using the volume control in the Squeezebox, it's one that is implemented in the digital domain. With the SB connected to a preamp, the volume of the SB should be set to max to ensure no bits are being lost.

Yes, I understand that. I use the pre-amp stepped attenuator at 10 o'clock (approx 1 o'clock when the Buffer is not installed) and this enables me to keep the SB volume control up near maximum, whilst achieving sufficient maximum volume on even the quietest recordings and maintaining remote volume control at the same time (no remote volume control on the pre-amp). Best of both worlds.

EDIT: The SB volume control needs to be kept above 16 (out of 40 max) on FW15, or approx 40 (out of max 100) for FW versions after 15 to eliminate any attenuator related sonic degredations. I always keep it above 30 (using FW15).

JoshK · « **Reply #9 on:** 15 Nov 2007, 10:18 pm »

Quote from: Roger A. Modjeski on 14 Nov 2007, 06:17 am

In the little box to the right marked Technical Fact, he defined "Impedance Matching" yet he is not doing this at all. In most systems the output impedance of the source is very low (0 to 1K ohms) and the input impedance that it is driving is quite high (50 to 500K ohms). Those are far from equal.

That is pretty funny. I am not sure if everyone caught the irony in that statement. Oops, my CD player has a Zout of 1K and my amp a Zin of 100K, I guess I need a buffer to make these two impedances match.

TomW16 · « **Reply #10 on:** 15 Nov 2007, 11:16 pm »

In at least one Burson buffer review, the Zout was between 15-30 ohms.

Cheers,
Tom

Roger A. Modjeski · « **Reply #11 on:** 18 Nov 2007, 09:22 am »

It is unfortunate that the term "matched" is being mis-used. All too often the consumer asks the question "Will this component match the other components in my system?" The salesman says "Yes" because that's what the consumer wants to hear. He also knows that neither he or the average consumer has any idea what properties constitute a match. Matching impedances by making them the same is not desirable and we actually want a large mis-match at almost every connection in the system. The proper match is to have the component driving output impedance very low and the following input impedance very high. If the input impedance of the power amp is 25k-100K ohms it matters not if the driving impedance is 1 ohm or 1,000 ohms or anywhere in between. Burson quoting that Arcam players range from 47 to 150 ohms and that other players range from 15 to 300 ohms reveals no problem whatsoever. We should be happy they are all so low. These don't need buffering, they are fine as they are.

The following is a statement from his advertising.

Burson Audio buffer removes any impedance mismatching by acting as an isolation platform between any source components (CD, DVD, SACD player, Phono preamp, radio, or even IPod) and downstream amplification (preamp, intergraded amp, etc). Burson Audio Buffer is designed to Increase signal transmission efficiency between all component and unlock the potential of any system.

satfrat · « **Reply #12 on:** 18 Nov 2007, 10:38 pm »

I have a HTPC going directly into my Sunfire Theater Grand 4 processor via digital cable from my sound card. Would this Burson Audio Buffer be a benefitial addition and what could I expect from it? I really have no issues and love what i now have,,,, but I am curious. Hell I'm always curious.

Cheers,
Robin

PS, a closer look at this unit seems to show that it only takes IC's, not digital cables. Me thinks I just saved some money.

Roger A. Modjeski · « **Reply #13 on:** 21 Nov 2007, 11:52 pm »

Yes, it is just a buffer amp with 6 dB of gain for analog signals.

Orson Garnsey · « **Reply #14 on:** 22 Nov 2007, 09:59 pm »

Interesting topic. I have a couple of different buffers around; a DIY buffer based on 6922s and a Musical Fidelity X-10v3. They have their uses. For example, I use an attenuator (passively) that has constant input/output impedance of 25k/25k (unlike using pots passively). My amplifier has an input impedance of 33k; somewhat lower than average.

A good buffer (hi z-in low z-out, good S/N) DOES help with a setup like this. The frequency extremes are somewhat better defined, particularly treble. This said, those who buy a buffer without an understanding of technical specifications and related system matching are wasting money.

Roger A. Modjeski · « **Reply #15 on:** 29 Nov 2007, 07:12 am »

I agree, there are some instances where a buffer will help. The most obvious is driving long cables from a not so low output impedance.

As to matching impedances, let me re-iterate that we don't match impedance "numbers" and that is why I suggest we remove the word "matching" from our thinking on this subject. A low driving impedance is always preferable to prevent high frequency rolloff. The input impedance doesn't matter so much as it is usually much higher than the driving impedance. Surprisingly, a lower input impedance will reduce the amount of rolloff. One can calculate this very easily. The 3 dB down point will be F=1/6.28RC where the R is the output impedance of the source in parallel with the input impedance of the amplifier being driven and C is the cable capacitance in farads.

Let us remember we are just making voltage dividers that happen to have a capacitor across the lower resistor.