Burmester 911 mk3

[microstrip]

Hi ,

A simple RCA to XLR adapter will not increase the impedance of the amplifier - normally it will short or connect the inverting phase of the input to ground with a low value resistor and use the non-inverting phase as RCA input.

AFAIK only an attenuator or a transformer can increase the input impedance.

 

[AudioExplorations]

Hi ,

A simple RCA to XLR adapter will not increase the impedance of the amplifier - normally it will short or connect the inverting phase of the input to ground with a low value resistor and use the non-inverting phase as RCA input.

AFAIK only an attenuator or a transformer can increase the input impedance.

It seems to be that since Burmester publish their input impedance specs as 23k unbalanced and 2k balanced, using the supplied adapter would result in these specs. I assumed that a live inverted phase pin would be recognized by the amp and that this activates additional circuitry resulting in a tougher load to drive. Perhaps I am over simplifying? Can anyone clarify?

 

[LL21]

At the risk of incurring the wrath of my wife - Gryphon blonde, Burmester brunette.

Oh brother...there are just too many ways this thread can go seriously wrong here. So let me just stop you there, Gary... Are you saying they are equally good...just taste? If so, how are they different? To be honest, i was expecting their sonic character to be more similar than different...incredibly powerful, effortless beyond effortless, transparent, extended...and slightly sweet in the treble, mids.

 

[LL21]

Hi ,

A simple RCA to XLR adapter will not increase the impedance of the amplifier - normally it will short or connect the inverting phase of the input to ground with a low value resistor and use the non-inverting phase as RCA input.

AFAIK only an attenuator or a transformer can increase the input impedance.

FWIW, Gryphon also is balanced only...and they also provide Neutrik RCA-XLR adaptors...but recommend permanent solutions...which i have now done by reterminating my ICs between the GAT and the Colosseum - RCA to XLR using Xhadow XLRs.

 

[garylkoh]

It seems to be that since Burmester publish their input impedance specs as 23k unbalanced and 2k balanced, using the supplied adapter would result in these specs. I assumed that a live inverted phase pin would be recognized by the amp and that this activates additional circuitry resulting in a tougher load to drive. Perhaps I am over simplifying? Can anyone clarify?

No, there is no active circuitry involved. The input is a differential input.

The Burmester RCA to male XLR adapters short pin 2 to ground, and connects pin 3 to the "hot" pin of the RCA - because Burmester (like many European amps) take pin 3 +ve and pin 2 -ve.

If you use a Cardas adapter or any other US-made adapter, you will short pin 3 to ground and connect the hot pin of the RCA to pin 2 - resulting in an amp that inverts phase. Because the 911 is a differential amp, you can just reverse the speaker terminals, and it "should be OK". Some have claimed to hear the difference, others claim to hear no difference. I think that it boils down to the comparison of the sound of the Burmester RCA-XLR adapter vs the Cardas adapter. A properly balanced differential power amplifier should sound identical whether a signal is connected to pin 2 or pin 3.

 

[AudioExplorations]

Thanks Gary! Does using a XLR-RCA adapter increase the input impedance to the published unbalanced spec?

 

[FrantzM]

Oh brother...there are just too many ways this thread can go seriously wrong here. So let me just stop you there, Gary... Are you saying they are equally good...just taste? If so, how are they different? To be honest, i was expecting their sonic character to be more similar than different...incredibly powerful, effortless beyond effortless, transparent, extended...and slightly sweet in the treble, mids.

I heard a Gryphon many years ago and don't remember much about it ... What you are describing is what I have experienced from Burmester. In that they remind me of another european stereo amp the Dar Tzeel .. I prefer the 911 ... other may not .. The sound is similar but IME the 911 sound "bigger",more dynamic, if that makes sense ... Could be becasue of power but overall there is abigness a dynamic bloom in the 911 that belies its relative output of 180 w/chat 8 ohm and about 300 in 4... The Burmester are as neutral as they come: their character is almost non-existent what is left is music with all the dynamics and bigness (if the score calls for it) of real music... They also drive most speakers with surprising ease ... I have never heard a 911 clip... I have seen the MBL 101 put some great amplifiers to their knees but the 911 acquitted itself quite well of this herculean task ... I think i really lke this amp and it's been that good for sooo long .. Worth repeating this ad infinitum

 

[garylkoh]

Thanks Gary! Does using a XLR-RCA adapter increase the input impedance to the published unbalanced spec?

No, which is why I am confused by the published specs. If it was two different inputs, one RCA and another XLR, Burmester could put in an additional buffer to raise the impedance of the RCA inputs. However, if it's just using an adapter RCA should be exactly half the input impedance of XLR.

 

[LL21]

I heard a Gryphon many years ago and don't remember much about it ... What you are describing is what I have experienced from Burmester. In that they remind me of another european stereo amp the Dar Tzeel .. I prefer the 911 ... other may not .. The sound is similar but IME the 911 sound "bigger",more dynamic, if that makes sense ... Could be becasue of power but overall there is abigness a dynamic bloom in the 911 that belies its relative output of 180 w/chat 8 ohm and about 300 in 4... The Burmester are as neutral as they come: their character is almost non-existent what is left is music with all the dynamics and bigness (if the score calls for it) of real music... They also drive most speakers with surprising ease ... I have never heard a 911 clip... I have seen the MBL 101 put some great amplifiers to their knees but the 911 acquitted itself quite well of this herculean task ... I think i really lke this amp and it's been that good for sooo long .. Worth repeating this ad infinitum

Thanks...although we all have different ears and different tastes...it seems that Burmester does have something akin to the Gryphon. This also seems corroborated by Joeinid (above) who is deciding amongst amps at the moment...and the 3 he is selecting from include CJ Premier 350, DTZL and the soon-to-arrive Burmester 911 MkIII monos.

 

[garylkoh]

Oh brother...there are just too many ways this thread can go seriously wrong here. So let me just stop you there, Gary... Are you saying they are equally good...just taste? If so, how are they different? To be honest, i was expecting their sonic character to be more similar than different...incredibly powerful, effortless beyond effortless, transparent, extended...and slightly sweet in the treble, mids.

The Gryphon I thought was a little more elegant, the Burmester a little more rich. But neither will have a "sonic character" per so. They are both transparent. Micro-dynamics on the Gryphon was a touch better, macro-dynamics on the Burmester a touch better - but both amplifiers are effortless beyond effortless. I've heard both amplifiers on the Genesis 2jr - which has it's own built-in bass amplification, so neither of them would be stressed. On speakers with big woofers to move, it might be a different matter.

 

[microstrip]

No, which is why I am confused by the published specs. If it was two different inputs, one RCA and another XLR, Burmester could put in an additional buffer to raise the impedance of the RCA inputs. However, if it's just using an adapter RCA should be exactly half the input impedance of XLR.

It is why I asked Jeff.
I remember another strange input specification - the Cello Duet 350. It had a balanced input with an input impedance of 1Mohm in one phase and 5kohms in the other. The RCA input was the one with high impedance.

 

[garylkoh]

It is why I asked Jeff.
I remember another strange input specification - the Cello Duet 350. It had a balanced input with an input impedance of 1Mohm in one phase and 5kohms in the other. The RCA input was the one with high impedance.

That would be BAD. By the very definition of "balanced", both phases must have identical input impedance. So, with this definition, the Cello would be a differential amp, but not balanced.

 

[AudioExplorations]

No, which is why I am confused by the published specs. If it was two different inputs, one RCA and another XLR, Burmester could put in an additional buffer to raise the impedance of the RCA inputs. However, if it's just using an adapter RCA should be exactly half the input impedance of XLR.

So the adapter should halve the impedance? I will call them tomorrow and find out.

 

[LL21]

The Gryphon I thought was a little more elegant, the Burmester a little more rich. But neither will have a "sonic character" per so. They are both transparent. Micro-dynamics on the Gryphon was a touch better, macro-dynamics on the Burmester a touch better - but both amplifiers are effortless beyond effortless. I've heard both amplifiers on the Genesis 2jr - which has it's own built-in bass amplification, so neither of them would be stressed. On speakers with big woofers to move, it might be a different matter.

ahhhhh...thank you! Very interesting! I suspect both amps will drive big low impedance speakers well, based on Jeff Dorgay's review which i just read.

 

[joeinid]

The Gryphon I thought was a little more elegant, the Burmester a little more rich.

I like "rich", so I am sure I will be very happy.

 

[AudioExplorations]

So the adapter should halve the impedance? I will call them tomorrow and find out.

I just called Burmester and spoke to the engineer Herr Benedix, he was in a meeting with Dieter Burmester and took time to talk to me, great service!

He confirmed:

• when using the supplied Burmester XLR->RCA adapter at the amp end (with an RCA interlink) the amp would be seen as a 22 kOhm load (it is 1.8k Ohm without use of the adapter)
• when using a third party adapter at the source end (with an XLR cable) the amp would also be seen as a 22 kOhm load
• when using an adapter with opposite polarity (i.e. the US Cardas) you should ideally change the pinout so that it is running in correct phase. He also mentioned that some say it doesnt matter and that it may not be audible, and that the speaker cables can also be reversed (at the speaker end) to achieve the correct polarity.

 

[AudioExplorations]

On speakers with big woofers to move, it might be a different matter.

Like these?

 

[FrantzM]

Heard the 911 on thse very speakers .. Drive these heavenly .. For some reasons these speakers are rarely mentioned in discussions here.. I find them very similar in sound to Wilson top of the lines..
I also experienced, not merely a few auditions but almost weekly for several months heard the 911 at a friend he had the Duntech Sovereign. The 911 drove them with ease and aplomb...

 

[joeinid]

I just called Burmester and spoke to the engineer Herr Benedix, he was in a meeting with Dieter Burmester and took time to talk to me, great service!

He confirmed:

• when using the supplied Burmester XLR->RCA adapter at the amp end (with an RCA interlink) the amp would be seen as a 22 kOhm load (it is 1.8k Ohm without use of the adapter)
• when using a third party adapter at the source end (with an XLR cable) the amp would also be seen as a 22 kOhm load
• when using an adapter with opposite polarity (i.e. the US Cardas) you should ideally change the pinout so that it is running in correct phase. He also mentioned that some say it doesnt matter and that it may not be audible, and that the speaker cables can also be reversed (at the speaker end) to achieve the correct polarity.

Joost,

Wow! That is great service. Thank you for calling and confirming. When I had my Conrad Johnson ET-5 hooked up to my stereo 911mk3 I was not crazy about the pairing. As much as I loved the ET-5 with everything else, I was not feeling it with the 911.

Joe

 

[joeinid]

Heard the 911 on thse very speakers .. Drive these heavenly .. For some reasons these speakers are rarely mentioned in discussions here.. I find them very similar in sound to Wilson top of the lines..
I also experienced, not merely a few auditions but almost weekly for several months heard the 911 at a friend he had the Duntech Sovereign. The 911 drove them with ease and aplomb...

It really is amazing how well the 911's do on a variety of speakers. I still have not heard the 911 on my speakers yet so I guess I am in for a treat.