Thank you All! Have it all connected and working PERFECT!!!
connecting mono amps to pre amp
Newbie here. I'm 56 and this past year and a half, I've gotten back into 2 channel. Various amps/pre amps and receivers. I would like to know how to properly connect (2) Mcintosh 2120's to a Mcintosh MA 6100. Have several mac pieces as well as others. But seems Mac is kind of like BMW/Mercedes -European cars with the fact of over engineering or over features, for a lack of better words. Can someone shed some light here with regards to the MONO bloc connection on these? Thank You in advance!!
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Yes, you understood correctly. When each of the amps is used in mono mode, and each amp is connected to just one 8 ohm speaker, you would use the 16 ohm tap (also referred to as the 16 ohm terminal). As mentioned earlier, be sure to also connect a wire between that 16 ohm tap and the 16 ohm tap for the other channel of the same amp. That is explained in the manual Tony (Tls49) linked to earlier. In mono mode the 16 ohm tap in effect becomes an 8 ohm tap, and the 8 ohm tap in effect becomes a 4 ohm tap, and the 4 ohm tap in effect becomes a 2 ohm tap, and the 2 ohm tap in effect becomes a 1 ohm tap. Regards, -- Al |
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Yes, as I said previously: The switch on the rear of the 2120 that selects between stereo and mono should be set to mono, as has been said.The fact that you are using two power amps in mono mode (one for each speaker), rather than a single stereo power amp, has nothing to do with how the 6100’s mode selector switch should be set. The 6100’s mode selector switch should be operated no differently than if you were using a single stereo amp, or the 6100’s built-in stereo power amp, to power the two speakers. Regards, -- Al |
The Mono(L+R) position of the switch will send the sum of the signals for the two channels (which is normally what is considered to constitute a "true mono" signal) into both speakers. But as can be seen in this photo it appears that other positions of the switch (the two left-most positions) are available that would play one channel through both speakers. Regards, -- Al |
yes, I actually have two tube amps that are paired up with a mac c 26 that are bi-amping a set of paradigms. sounds really good. Just looking at some options with the ma 6100 and the two 2120's. as mentioned in my user name I have some other pieces, sound craftsmen, nikko, marantz, kenwood. and a couple of pioneer spec pieces, still looking for a couple of other spec pieces to finish up that rack of stuff, My wife thinks I'm NUTS!!! buat as I told her I'm home more often since the Harley, and vette are gone. anyway, i really enjot the 2 channel stuff! |
That’s a good suggestion, Mb1, assuming as you say that the speakers can be biamped. To clarify, however, when the OP’s amp is used in mono mode it is not bridged. The two channels are paralleled, as I mentioned, via their output autoformers. That is of course different than bridging. And depending on the specific design the result could very conceivably be no sonic downside, in contrast to the downside that is often attributed to bridging. Regards, -- Al |
Not to confuse you, but since you already own both amps, you may want to try a vertical biamp. (I'm assuming your speakers have 2 pairs of binding posts). For the most part, people feel that bridging a stereo amp degrades sound quality. How much will vary from system to system. A vertical biamp will allow you to use both amps unbridged and avoid any power differences that usually come up with horizontal biamping. If you want more info, have a look at this. http://vandersteen.com/audio-perfectionist-journal Personally, I think APJ is the best reference on high end audio ever written. There's an incredable amount of useful information in it. |
The switch on the rear of the 2120 that selects between stereo and mono should be set to mono, as has been said. The mode selector switch on the front panel of the 6100 should be set to stereo, assuming you are listening to a stereo recording. Setting it to mono would result in both speakers putting out the same sound, corresponding to the sum of the two channels of the recording. Assuming you are playing a stereo recording, what you want is for the left speaker to play the left channel of the recording and the right speaker to play the right channel of the recording. No damage would result, though, regardless of which of those positions the switch is set to, and regardless of whether a stereo or a mono recording is being played. The result would just be that the sound and the imaging would not be right, if you were to play a stereo recording in mono mode. If you are playing a mono recording though, it would be preferable to set the mode selector switch on the front panel of the 6100 to mono, although it might not make much difference if you leave it in stereo. Regards, -- Al |
You're welcome, 2channeladdicted. Just be sure to keep in mind the following statement in the 2120's manual: Should the MODE SWITCH be left in the STEREO position and the output transformers be strapped for a monophonic load, one channel will attempt to drive the other and cause circulating currents and overheating. Be certain that the MC 2120 is never operated in the stereo mode with the outputs connected for monophonic operations.Regards, -- Al |
Thank you all!!! You guys are a plethora of knowledge! never have had the opportunity to utilize mono application in my younger years,,,,LOL. have a couple of tube amps that I'm using with a mac c26, but using those to bi -amp a set of paradigms so a little different than trying to do the MONO thing. Thanks again! |
Thanks, Tony (Tls49). As you realize, my comment and the one by Mb1audio02 did not address the connections between the amps and the speakers, since they were not asked about by the OP. The manual you linked to indicates that for mono use the two channels on each of the amplifiers are paralleled, so what you stated in the last paragraph of your first post is correct with respect to the speaker connections. It should also be noted, though, that the tap which should generally be used (assuming the speaker’s nominal impedance rating is reasonably accurate, which of course is not always the case) corresponds to the nominal speaker impedance multiplied by two. In other words the paralleling of the channels results in what is designated as the 16 ohm tap becoming an 8 ohm tap, and what is designated as the 8 ohm tap becoming a 4 ohm tap, etc. I would expect, though, that connecting the speaker to the appropriate right channel terminals and jumpering the right channel tap that is used to the corresponding left channel tap would work equally well. Best regards, -- Al |
"then you would bridge the common/negative on the speaker terminals" No, use "COM" terminal on left channel output to speaker negative, then if your speaker is 8 ohms, connect "16" terminal on left channel to speaker positive. Also, connect a jumper from "16" terminal on the left channel to the "16" terminal on the right channel. Not sure why manual shows 2 speakers connected in mono operation, however I’m reading the instructions for my comment. |
the two 2120's can be run as mono i believe as stated in the owners manual with using the right channel only and then bridging the common? last question when bridging the common on the amp you are using for the left channel speaker you would also bridge the common on the right channel amp you are using for the right speaker? In the 2120 manual it shows using 2 speakers with only one amp in MONO. Sorry to sound so confusing but just want to make sure nothing gets FRIED!!! |
so If I under stand this correctly the left out of the 6100 will go to the right on one of the 2120's and the right out will go to the right of the other 2120. then you would bridge the common/negative on the speaker terminals. In addition on the front of the 6100 the mode position would be in the MONO setting that states (MONO) L + R . Is that correct? and MANY thanks! |
In addition to Al’s comment and hopefully he will verify or correct if I am not. After looking at the MC2120 manual here, http://www.berners.ch/McIntosh/Downloads/MC2120_own.pdf You actually connect the speaker to the left channel output of the 2120 for mono operation. Negative of the speaker to the "COM" terminal on the amp and positive of the speaker to the appropriate impedance number tap with a jumper from that tap to the same impedance number tap on the right channel output. |
What mb1audio02 said is correct, although given your response what he said may not have been worded as clearly as it might have been. You would connect an interconnect between the right channel input of the right channel amp and the right channel "preamp" jack of the 6100. You would connect an interconnect between the right channel input of the left channel amp and the left channel "preamp" jack of the 6100. The left channel input of each amp would be left unconnected. You would set the rear panel switch on both amps to mono, as you indicated. Regards, -- Al |
I'm trying to connect (2) 2120 power amps and run them as MONO the Ma 6100 has only 1 set of pr amp jacks. and 1 set of power amp jacks, The 2120's have a left and right gain on the front and stated in the manual that if you run the amps as mono to the RIGHT only as it is designed to run as mono. and to switch the button on the back of the amp to mono. |
