Mackie Thump 12i 2-Way Active Speaker

[agreen96]

Hello I bought a used "Mackie TH-12A Active Sound Reinforcement Loudspeaker" about 3 months ago from a local music shop and have been using it during band practice (~1x a week for 2 hours) for my vocals.

Basically, my mic goes through a separate pre-amp (API 512c) for easier volume control and then goes into the Mackie input. The mackie volume was always at 12 o'clock and the preceding pramp volume was similar so I wasn't doing anything crazy.

- It was in good condition when I bought it and I haven't had any issue until last practice where:
1. The bass in the output is practically gone (sounds like a high-pass filter is on and all the EQ controls have always been @ 12 o'clock)
2. The audio starts going in and out
3. There is a strong fuzziness that makes it sound like a radio

#1 and #3 occur at any volume levels
#2 doesn't occur until the input sound reaches some volume threshold.

I have tried several different microphones and cables but the issue persists. (Also persists going directly into the Mackie from the mic and skipping the separate preamp)

I took it back to the shop and of course it is out of warranty but the guy out front (who wasn't a repair tech but offered to give a quick look) said he didn't think anything was wrong which I thought was strange because it is clearly not working properly.
I would have to pay some minimum amount to have a tech even look at it at all so I want to gather some information before I make a decision.

Here is the speaker in action in it's current state:
#1 -

#2 -

#3 -

From video #1 I believe the horn speaker is fine and the issue might be the woofer.

I have never done any repair or diagnosing of audio equipment before so I am not really sure though.

I did a search on these forums for any posts related to Mackie's and I saw this one https://audiokarma.org/forums/index.php?threads/mackie-thump-15.662238/#post-8827528 where GordonW's comment seemed to describe what my woofer appears to be during quite accurately.

I reckon this means that this is probably not an issue w/ the electronics and just the woofer needs to be reconed or entirely replaced?

If it matters I see in the manual (https://www.manualslib.com/manual/258442/Mackie-Th-12a.html) that it has:
- 100W HF and 300W LF power amplifiers (peak)
- 12" low-frequency woofer
- 1" high-frequency compression driver
- Flat frequency response (-10 dB, 57 Gz to 20 kHz)
- 24 dB/octave crossover at 3 kHz
- Low-frequency over-excursion protection

If anybody has any insights on what the issue could be, I would very much appreciate it.

Thank you

*Edit 2023-07-23 5:26PM EDT: The model listed on my receipt was wrong and I just noticed after looking on the speaker itself. It is not a Mackie 12i but is a 12A, I updated the information above to be correct

 

[Dswankey]

If it were me I would go straight to the source as Mackie is still in business and it looks like they have a good support section on their site

Tech support request | MACKIE

mackie.com

MACKIE

Mackie products have been making music across a wide-range of applications since our founding in Woodinville, WA in 1988.

mackie.com

 

[MuseChaser]

I second the recommendation to contact Mackie; their support is generally pretty good.

A couple questions, just to rule some possibly obvious stuff..

When you tried plugging the mic directly into the Mackie powered speaker, did you plug it into the appropriate input (a mic level input, and not a line/instrument level input)? Microphones output a much weaker signal, and require more preamplification.

Are you using a dynamic mic or a condensor that requires phantom power?

When you used the external API preamp, was gain-staging managed well, meaning was the trim and/or gain set on the API for a strong signal but with adequate headroom before distotion, prior to sending the signal to the Mackie? I ask because of the statement regarding all levels set at "12 o'clock... nothing out of the ordinary"... which would usually be out of the ordinary. Is there an metering present on the API or the Mackie? If so, make sure you're getting close to full scale w/out any "red" indications on your preamp, and then advance the volume on your speaker as required.

In the last video, when you repeatedly cranked the volume on the Mackie up to full scale, that should have created absolutely ear-killing volume. Either something is drastically wrong with Mackie, or you're feeding it a very weak signal, possibly into the wrong input.

What did the clerk at the store do to test it and proclaim that it seemed to be working ok?

 

[agreen96]

Ah I should have thought of that, I created a help ticket on Mackie's site.

I believe I plugged it into the appropriate input; there is only one input available. As for whether plugging a mic in directly is supported usecase, I believe it is as shown in the diagram below which was extracted from the manual.

I have tested with a Sennheiser E935 Dynamic Vocal Microphone and also a Sennheiser MD 421-II with the same issue. The shop clerk also tried with his own mic and had the same issue. I do not think phantom power is the issue.

The dimensions of our practice space are: 8'8" x 15'10" x 9'4" (Width x Depth x Height) so everybody is pretty close.

The API preamp has a meter and the Mackie has a red LED that turns on when the signal is too strong.

I will be honest I probably was not paying enough attention to making sure I was pushing it too far because I was (wrongly) trying to make sure it could be heard with the drums, bass, and both guitars in the space. When I did quick vocal checks before practice began I don't think I was in the red with the API or Mackie but I probably reached higher volumes when I was shouting during actual practice.

Also I should mention that sometimes the screeching feedback thing would occur since the mackie output is in the direction of the mic itself (because we have so little room to work with). Could just one of those occurrences have killed the woofer?

Do you think it would be correct to say that I should've gotten something more powerful to reach the levels needed?

Also, the model listed on my receipt was wrong and I just noticed after looking on the speaker itself. It is not a Mackie 12i but is a 12A, I updated the information above to be correct

Also, it is possible to edit the title for this post? I have the wrong Mackie model listed in it. I cannot locate the edit button for the title.

 

[MuseChaser]

I can't make it out in your pics (resolution too low), but I'm guessing that button in the top right of the panel is a switch between mic and line level. Make sure it's set correctly.

Edit: How could the clerk have "had the same issue," but also stated that the speaker was working correctly?

 

[agreen96]

The top right button is to enable/disable the EQ dials. There is no switch between mic and line level. This speaker worked greater for a couple months during band practice.

For some reason he didn't understand that the bass was almost completely gone during his tests and the audio didn't start going in and out until he got loud enough where the overloaded LED came on so he thought I was just putting too much in earlier when this is not the case.