Markbass Mini CMD 121P - simplest of upgrades

[Chienmortbb]

[quote name='eddiehoffmann' timestamp='1491400945' post='3272737']
Unfortunately that's not the case. Even with the L-pad turned all the way down there's still a little bit of signal coming through the twitter. I can still hear its annoying noise and I can tell there's a little bit of signal being reproduced. Specially with fuzz. Fuzz and twitters are a match made in hell by satan himself.
[/quote]On the Basschat 1x12 Mk2 you can see how complex the crossover design is. That was to get the 12" and Compression Horn or tweeter to sound good together. You cannot just bump a tweeter in and expect good results. Unfortunately even many boutique makers cut corners (and I am not talking kickback cabinets here).

The reason you need a tweeter is that a 12`` speaker ends low frequencies everywhere but mids and highs go straight down the middle. Go 45 degrees offline and you might as well be listening to a fart in a plastic bucket filled with foam.

[fftc]

[quote name='Chienmortbb' timestamp='1491575326' post='3274091'] Go 45 degrees offline and you might as well be listening to a fart in a plastic bucket filled with foam.
[/quote]

That is exactly the sound I'm after!

[eddiehoffmann]

[quote name='Chienmortbb' timestamp='1491575326' post='3274091']
On the Basschat 1x12 Mk2 you can see how complex the crossover design is. That was to get the 12" and Compression Horn or tweeter to sound good together. You cannot just bump a tweeter in and expect good results. Unfortunately even many boutique makers cut corners (and I am not talking kickback cabinets here).

The reason you need a tweeter is that a 12`` speaker ends low frequencies everywhere but mids and highs go straight down the middle. Go 45 degrees offline and you might as well be listening to a fart in a plastic bucket filled with foam.
[/quote]

Well... I never needed a tweter in a bass cab in more than 20 years playing. Always heard myself really well and always have been complimented on my tone. The only time I can't get a good rig sound like I want to is when there's a tweeter I can't get rid off.

[eddiehoffmann]

I'll open up the cab again tomorrow and get rid of it one way or another. Any advice other than telling me I need a tweeter is more than welcome.

[Muppet]

Well I had a look inside the cab. The speakon inputs are connected directly to the crossover. Red goes straight to the driver, Yellow labelled 'twr' goes to L Pad and blue goes from L Pad to the tweeter itself. It's dead easy to disconnect the tweeter obviously but wouldn't you want to bypass the crossover too, otherwise you've higher frrequencies being directed off in to nothing?

Edited April 7, 2017 by Muppet

[eddiehoffmann]

[quote name='Muppet' timestamp='1491593126' post='3274226']
Well I had a look inside the cab. The speakon inputs are connected directly to the crossover. Red goes straight to the driver, Yellow labelled 'twr' goes to L Pad and blue goes from L Pad to the tweeter itself. It's dead easy to disconnect the tweeter obviously but wouldn't you want to bypass the crossover too, otherwise you've higher frrequencies being directed off in to nothing?
[/quote]

That's what I thought too. Thanks for that man! I'll gladly leave anything above 5Khz to the keyboard players and guitarrists to have fun with

[dannybuoy]

Do you know what the crossover frequency actually is though?

[eddiehoffmann]

[quote name='dannybuoy' timestamp='1491609243' post='3274352']
Do you know what the crossover frequency actually is though?
[/quote]

It's 3.5Khz and obviously the 12" can reproduce frequencies higher than that. Besides, I think this rig (and other Markbass rigs I tried) can sound a bit boomy and running the combo without crossover I felt that problem was also solved.

Edited April 8, 2017 by eddiehoffmann

[Chienmortbb]

I am happy if you get what you want by disconnecting the tweeter. I give my advice freely, you can use it or ignore it as you feel fit.

3.5 KHz is fine from most 12" drivers but only on directly in front, 45 degrees either way loses 6dB and that is only 1/4 of the volume on axis. So people to the side I the room do not hear what you hear.

On the plus side the 3.5KHz crossover point is useless to counteract the "beaming" of the12". So it really does nothing for your sound.

[eddiehoffmann]

[quote name='Chienmortbb' timestamp='1491673492' post='3274726']
I am happy if you get what you want by disconnecting the tweeter. I give my advice freely, you can use it or ignore it as you feel fit.

3.5 KHz is fine from most 12" drivers but only on directly in front, 45 degrees either way loses 6dB and that is only 1/4 of the volume on axis. So people to the side I the room do not hear what you hear.

On the plus side the 3.5KHz crossover point is useless to counteract the "beaming" of the12". So it really does nothing for your sound.
[/quote]

I used a tweeterless Barefaced Super 12 for two years and thought the tone and dispersion of that cab were amazing. I also used a pair of Eden EX112s (also tweeterless but with the whizzer cone) and even thought they didn't handle as much power and low end as the Barefaced I never had a problem with dispersion in all sorts of weird positions in relation to the rig.

I imagine a full range system will reproduce more frequencies and maybe have more clarity and dispersion, but that's not what a bass guitar should sound to my ears.

Edited April 8, 2017 by eddiehoffmann

[Muppet]

I'd be interested to see how you take the crossover out of the loop. To be honest, I'm going to leave it. I've bypassed the tweeter in the combo (so amp>driver) but I can put up with just using the L Pad on the extension cab.

Another unrelated thing I found is that the driver in the Italian made cab is exactly the same as in the Indonesian made combo. I was led to believe that these were different.

[eddiehoffmann]

[quote name='Muppet' timestamp='1491722083' post='3274921']
I'd be interested to see how you take the crossover out of the loop. To be honest, I'm going to leave it. I've bypassed the tweeter in the combo (so amp>driver) but I can put up with just using the L Pad on the extension cab.

Another unrelated thing I found is that the driver in the Italian made cab is exactly the same as in the Indonesian made combo. I was led to believe that these were different.
[/quote]

What confused me before is that all the wires were bundled together with cable ties and I wasn't quite sure what was what and to which connector it was going to inside the cab. Once I got rid of the cable ties it was easy to isolate the two wires (red and black) that I needed to connect the input connectors directly to the speaker. I used cable ties again to tidy up the unused wires that are stil connecting the L-pad and the tweeter but no longer in my circuit and job done. The 12" does sound different and, to my ears, better in full range mode.

[gsgbass]

[quote name='Lozz196' timestamp='1373760935' post='2141450']
I`ve never worried about the sound from the tweeter, but I would like a control for it the same as the NY121 cab has.
[/quote]

A tweeter control on the Mini CMD 121P would be a nice touch.

[Muppet]

[quote name='eddiehoffmann' timestamp='1491727297' post='3274988']


What confused me before is that all the wires were bundled together with cable ties and I wasn't quite sure what was what and to which connector it was going to inside the cab. Once I got rid of the cable ties it was easy to isolate the two wires (red and black) that I needed to connect the input connectors directly to the speaker. I used cable ties again to tidy up the unused wires that are stil connecting the L-pad and the tweeter but no longer in my circuit and job done. The 12" does sound different and, to my ears, better in full range mode.
[/quote]

How did you connect the red and black to the input?

[Chienmortbb]

[quote name='fftc' timestamp='1491576986' post='3274108']


That is exactly the sound I'm after!
[/quote]Not often someone makes me laugh in here but that tickles me.

[Beer of the Bass]

[quote name='Chienmortbb' timestamp='1491818773' post='3275528']
Not often someone makes me laugh in here but that tickles me.
[/quote]

Well, Dusty Hill did once describe his bass sound as "a rhino farting into a trash can"!

[Dood]

[quote name='Beedster' timestamp='1272907586' post='826689']
I'm never quite sure how [i]badly designed crossovers and[/i] tweeters[i] that aren't fit for purpose[/i] got into bass cabs anyway?
[/quote]

Added a bit

I think the biggest problem with tweeters in bass cabinets is that the design used to include them is the very thing that makes us want to exclude them, if that makes sense. Poor designs where the woofer's high frequency falls off before it reaches the low frequency content of the tweeter leaves a massive hole in the sound. A notch in the frequency spectrum if you will. With these frequencies missing, you often get the effect that the sound is coming from two different sources rather than one cohesive output. The crossover on the tweeter has to be sufficiently high so that low frequencies are limited as they can damage the cheaper units often used in bass combo amps. That often widens the gulf between what the woofer is offering and what the tweeter is now capable of reproducing.

Now, add in to the mix a nice set of flats that have been gigged to death or a passive bass with the tone control dialled back and lets face it, the tweeter is only getting what's left over in it's frequency range: A bit of clack and a fair amount of hiss from the power amplifier.

A premium cabinet with no expense spared on crossover design and components offers a marked difference in clarity, quality of tone and cohesiveness between the tweeter and woofer outputs.

So, to sum up, yes in many cases, I can't see the point in just throwing off the shelf components in to a bass cabinet. A big thumbs up to the companies who are doing it right.

[stevie]

Well said, Dood. However, the companies that are doing it right are a lot rarer than you might think. One, maybe two boutique companies, I'd say. The others talk the talk and make extravagant claims, but have exactly the same attitude as Markbass.

I think the fact that you can improve a bass cabinet from one of the industry's prestige manufacturers by taking out one of the drivers speaks volumes about the products that we bass players are being served up nowadays.

Still, these manufacturers want to stay in business, and why should they spend money on the internals when bass players continue to give their products rave reviews? Cost cutting doesn't seem to have done Markbass any harm.

[eddiehoffmann]

[quote name='Muppet' timestamp='1491800446' post='3275384']
How did you connect the red and black to the input?
[/quote]

From the plate with all the spade connectors on the back... There's a pair with 'input' written on it and another one with 'ground' ( I think it's abbreviated) written just bellow it. Red wire on INPUT, black wire on GROUND and then red wire connects to the speaker where you can see a little red dot right next to the spade connector. Black wire on the remaining one on the speaker.

[eddiehoffmann]

[quote name='stevie' timestamp='1491825323' post='3275600']
Well said, Dood. However, the companies that are doing it right are a lot rarer than you might think. One, maybe two boutique companies, I'd say. The others talk the talk and make extravagant claims, but have exactly the same attitude as Markbass.

I think the fact that you can improve a bass cabinet from one of the industry's prestige manufacturers by taking out one of the drivers speaks volumes about the products that we bass players are being served up nowadays.

Still, these manufacturers want to stay in business, and why should they spend money on the internals when bass players continue to give their products rave reviews? Cost cutting doesn't seem to have done Markbass any harm.
[/quote]

I would be really interested to know which boutique companies you think are doing it right. I still don't want any tweeters, properly done or otherwise, anywhere near my cabs, but I'm curious to know what are these companies and how the differ from companies such as Markbass, Aguilar... Please note I'm not being sarcastic. I'm literally just curious about it.

Edited April 10, 2017 by eddiehoffmann

[eddiehoffmann]

[quote name='Beer of the Bass' timestamp='1491819358' post='3275537']
Well, Dusty Hill did once describe his bass sound as "a rhino farting into a trash can"!
[/quote]

My tone goes from purring kitty to wild boar on heat. That's pretty much the range of it

Edited April 10, 2017 by eddiehoffmann

[stevie]

[quote name='eddiehoffmann' timestamp='1491840655' post='3275791']
I would be really interested to know which boutique companies you think are doing it right. I still don't want any tweeters, properly done or otherwise, anywhere near my cabs, but I'm curious to know what are these companies and how the differ from companies such as Markbass, Aguilar... Please note I'm not being sarcastic. I'm literally just curious about it.
[/quote]

If I were to name names, the fanboys would be on me like a ton of bricks, especially as I can't claim to have have examined every bass cab on the market. So I'll have to pass on that one. But there's nothing to stop anyone posting a photo of the interior of their cabinets if they think the manufacturer has done a great job.

[FHB]

Does this mod make the amp sound more like the 121H? Honestly much preferred the 121H, definitely had more detail in the sound when I tried it out @ Andertons. No idea how it sounds with a loud drummer, sax and guitarist, but it felt more defined than the P. The only thing is... as lovely as they sound, Markbass definitely are things to buy used... And I can't find any 121Hs for sale...!

[yorks5stringer]

There were a couple in the classifieds here about 4 weeks ago...

[Johan]

Found this post and realy thought it was the answer to my problems. In my case it was a bad instrument cable witch i found out later on. I did do the conversion and connected the amp directly to the 12” speaker. My impression Of this conversion was that the speaker ended up sounding dull and lacking all of its ”hifi” brilliance. Posters on this forum says, that the 12” speaker is very capable to produce the high frequencies without the piezo horn. I dont agree. In my case the horn was not broken. The only reason for disconnecting the filter and horn, in my opinion, is if the horn really is broken and producing bad noice, but it wont be as good and clear playing as with the original setup. My opinion only. The conversion was easy to do and undo.

/ Johan