Hey gearspace friends,

I purchased a 2nd hand pair of MM5X from a guy in France for my mastering studio and I have some questions.
I brought them home and tested them for some time but the sound is kinda weird in the low end and the mids feel phasey. I told the guy and he told me that he always had a dip in the 100hz - 200hz range in 2 rooms he used these same speakers. I mesured them with Room EQ Wizard and even if i see some of my big room modes in the results I clearly see some weird behavior in the low end and i don't understand since a lot of people seem to be hapy with them, praising how it's easy to work in the low end for mastering. I don't know whats is the exact problem but the sound feels phasey and not solid on the low end. I'm reaching out to you for some help, how could i test what's exactly wrong with them please? I have some multimeters and beginner soldering skills and i would do anything to make them sound better but i just don't know how to do it.
I included some measurements and the REW file to show you how they measure in my room, but since the guy told me he had the same issue in 2 of his rooms the problem doesn't see to be room dependant.

Since these are 2nd hand, first thing that I would do is to make sure that you don't have a reverse polarity.

Check the positive and the negative wires between the speakers and the amplifier if they are crossed, then open terminal connector on the back of the speakers and make sure the positive and negative wires for each driver are not crossed.

As Razik said :

If you are using them single amplified and stereo, be sure that you have the wires between positive top to bottom plugs and negative top to bottom plugs, at the back, connected.
It's easy to loose one woofer/side with those wires.

I use those speakers for 10+ years and i like them.
I have change the tweeter and tweeter's resistor. I use them bi-amp with 2x500W monoblocks amps per side. They are super fast, and precise.
Everytime a client comes to my room, he is asking if I have subs somewhere.

I hope that helps.

Ok, I get it for the cables between amplifier and speakers but what do you mean to check if wires are not “crossed” in the terminal connector please?

Edit: I attached pic of the terminal connector of each speaker.

How do you bi-amp them ? I saw passive speakers with multiple inputs connectors on the back but on the MM5X there are only a pair for one amp (on mines at least)

Woaw!
Mine have 4 plugs each with jumpers that you remove to biamp.
Bottom for woofer top for mid+high.

It could be 2 wires inside. Have a look and put a plate with a speakon NL4.

Make sure positive (+) from the amp goes to positive (+) or red on the speaker. It should be the same for both speakers.

It does, I attached pics on my answer with terminal connector opened too.

The wires on the terminal connector look good. What kind of amplifier are you using?

Tyler owner here too, for the past 8 years. I'm sorry to hear this. It does seem like there's something goofy going on. I just wanted to encourage you... sorry about the troubles.

Interesting that you are having 3 wires going out of the connector.
Could be a different filter type than mine.
It seems that the tweeter's resistor, i can be wrong, is right there instead of between the tweeter and the filter.
Easier to tune/tweek, maybe

Hypex NC502MP, but I tested an another amplifier and it was the same thing.

Thank you ! I suspect there is something going wrong too because owners seem to be very happy with them! I correct them with Dirac Live for now and they sound really nice with the correction but the amount of correction applied is insane and especially on the low end ������

It could be the case but wouldn’t it be strange to reduce the load with a resistor before the sound gets filtered? I might say something really dumb but it’s not logical for me.

I'd be checking that the polarity of the wiring is correct at the drivers themselves too. Driver replacement is perhaps the most common repair to monitors and a potential source of errors.

It might be worth getting in touch with Tyler or having a service manual as drivers are sometimes intentionally wired with reverse polarity to account for phase shift in the crossover network. Ideally that's done at the crossover to avoid confusion, but you never know !

I sent him a message.
I talked with the previous owner and he told me that no modifications were done on the speakers or whatsoever.

Edit: I attached pics of the woofer wiring, everything seems fine, both of them are wired like this.

I know it's a weird test but it's the only way i could show you what's going on in real life situation.
I recorded a sample of some music which is bass and sub heavy (Hippie Sabotage - Get Out My Own Way) with a measurement mic, first you hear the speakers corrected with Dirac with nice solid bass and then you hear the speakers without correction, the sound becomes honky in a weird way and the bass is really hollow, I put back Dirac on after that for easy A/B. Don't know if it could help some of you to know what's going on but i try my best haha.
(mp3 because of gearspace file size limit)

If the speakers sound good after you applied Dirac Live room correction, it is possible that you don't have phase shift problem, but it could the placement of the speakers in the room and the acoustic treatments. However, if Dirac Live is working for you, there is nothing wrong with that.

Dirac saves me for now but I can’t get out of my head that there’s something wrong. Previous owner confirmed that he had the same feeling in 2 different rooms (and the solution for him was also Dirac). It’s doing a great job for correcting what’s wrong but the drivers are really solicited to get bass at a good level, and I’m afraid that I get good frequency response at the cost of distortion.
Dirac is a solution but isn’t it strange that the stock sound of a big speaker like this is really thin and honky? I really get the same feeling as when you’re recording a kick drum and the 2 mics are out of phase, the bass gets lost and the sound is thin.

Hey, if you have MM5X, could you share measurements of them in your room please? As we can see on my measurement, the low end region is on average 10db lower than the rest, it could be helping to see how it compares to yours.
Again, i'm asking this because there have been 3 rooms of diffenret geometry tested with same results.

Thanks