@georgehifi
As I've indicated multiple times, the amp is not being bridged!
Regards,
-- Al
As I've indicated multiple times, the amp is not being bridged!
Regards,
-- Al
What does an impedance-matching issue "sound" like?
I recently added a 2nd Luxman MQ-88uSE to my 2 channel system, bridged to mono so I am running a Luxman to each of my 6ohm Volti Rivals.
The SE version of this Luxman amp only has single speaker taps which output 25Wpc to 6 ohms, and 20Wpc to 4 ohms and 8 ohms (from the manual). I used a jumper between each of the "positive" taps so I am not sure what the bridged output is to the 6 ohm Rivals.
Now what I am hearing is definitely more power and presence in the sound, better bass, as well as improved separation. BUT occasionally I am hearing what sounds like a bit of breakup deep in the mix of some songs. Like the whole channel isn’t breaking up, but suddenly a rhythm guitar part sounds noisy like it’s being played through an AM radio or something. On some songs, the entire mix may sound reduced in scale and less dynamic.
I am not sure if my ears are playing tricks on me, or if I’m crazy, or if there could be something happening in the pairing of these amps and speakers that is bad for the equipment and sound. I realize this is a complicated issue because one amp is brand new and the other is broken in, and they are both tube amps., So chasing down the culprit could get messy.
Is it possible there are impedance issues at play here? What would that sound like?
The SE version of this Luxman amp only has single speaker taps which output 25Wpc to 6 ohms, and 20Wpc to 4 ohms and 8 ohms (from the manual). I used a jumper between each of the "positive" taps so I am not sure what the bridged output is to the 6 ohm Rivals.
Now what I am hearing is definitely more power and presence in the sound, better bass, as well as improved separation. BUT occasionally I am hearing what sounds like a bit of breakup deep in the mix of some songs. Like the whole channel isn’t breaking up, but suddenly a rhythm guitar part sounds noisy like it’s being played through an AM radio or something. On some songs, the entire mix may sound reduced in scale and less dynamic.
I am not sure if my ears are playing tricks on me, or if I’m crazy, or if there could be something happening in the pairing of these amps and speakers that is bad for the equipment and sound. I realize this is a complicated issue because one amp is brand new and the other is broken in, and they are both tube amps., So chasing down the culprit could get messy.
Is it possible there are impedance issues at play here? What would that sound like?
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- 38 posts total
@almarg Ooops sorry, just saw what he said in the first sentence. added a 2nd Luxman MQ-88uSE to my 2 channel system, bridged to mono so I am running a Luxman to each of my 6ohm Volti Rivals In any case that phase/impedance load around 100hz is nothing that tube amps want to be seeing. https://www.stereophile.com/images/617Voltifig1.jpg Change the amps if you want to keep the speakers. or visa versa Cheers George |
Thanks guys, this is all a little confusing to me as both the speaker mfg and the dealer who sold me on running 2 Luxmans said there would be no issues. 95% of the time this sounds amazing, and I do hear the benefits of a more powerful sound and better separation between channels. But that fuzzy sound in some of the midrange on some material is what brought all this up. Hate to think that I'm stuck with these amps now if all I've done is decrease the quality of my sound. Also regarding tube amps and the Rivals, they are voiced with Border Patrol SET amps which are used to demo the speakers at all the shows, etc. So I don't think tubes are the issue, but it's the 3 ohms into a 6 ohm speaker part that has me concerned. |
So I don’t think tubes are the issue, but it’s the 3 ohmsThat 3ohms at 110hz with -50’ phase angle at 75hz to me is an issue, especially with SE tubes, this is where all the amps power is needed for bass repoduction. I find it hard to believe a speaker manufacturer would voice a speaker with this kind of load graph with "feeble" SE Border Patrol amps, that are probably good amps with the right speaker, easier loads than this.. Cheers George |
- 38 posts total