• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Tweeter Hiss on Markbass CMD1020p

Accostingwalrus

Accostingwalrus

Nov 26, 2018
8
5
Upstate NY
#1
Hey fam, I have a Markbass CMD1020p combo amp. Its a 2x10 with a piezo tweeter. There is a background hum/hiss that i believe is coming from the tweeter. If i turn down the high end the hiss goes away so its definitely tweeter. And its there when the amp is on but not plugged into a bass. The amp sounds soooooo good, the tone is so warm and when i turn up the volume the bass hugs my soul. But the background hiss gets a little annoying, which is why im asking if there is anyway to reduce the noise without turning down the high end (love me some slaps)
 
  • Like
Reactions: TrevorG
#3
That was a real fault of those combos. Those LeSon piezo tweeters don't really do anything useful to the sound. They start so high, far higher than any really useful low-treble that they just end up hissing and occasionally reproducing string squeak. They should have put compression drivers in those. My NY121 barely ever registers any sound out of its piezo tweeter.

There's no harm in dialling back the treble to stop that hiss. You might want to also look at your signal chain. Your bass might be hissing if it's active. My TRB1005j hisses quite a bit if I boost the onboard treble. My Laklands don't hiss nearly as much.
 
  • Like
Reactions: TrevorG
#5
Disconnect the tweeter; that always makes bass amps sound better (to me). I still have the tweeter connected on my Minimark and I don't recall there being too much (any, really) hiss from it.
 
#9
Here's my solution... Girlfriend's crocheted "granny squares" : )
MBCrochet.JPG
 
  • Like
Reactions: seamonkey
#10
What all the Markbass hiss complainers/whiners neglect to mention is you need be ear level right in front of tweeter. If you stand up or move slightly away you can't hear it. And of course when you actually play it's moot.

A lot of electronics have some high frequency noise home or Pro and if you have a teeter that has good output in that range you will hear some noise with ear up to tweeter in quiet room; So What!
We all know tweeters don't hiss?

Some tweeters with less output/response or Compression Horns [no real highs] may mask electronics noise/hiss somewhat.

If the Amp/Speaker combination sounds great when using it that's what counts and in this instance The Markbass amps/Speakers are quality sounding products and competitive with anything in there price range. There are other great amps out there maybe with technically better tweeters[to me many [not all] horns are not better; harsh and hard if not cut a lot]

I don't and never have heard any negative effects of P tweeter on overall sound in Markbass Cabinets.
I do notice with tone/EQ set for Slap and Pop you get the 'Ping' sound with Markbass when you pull, I have heard a lot RnB and Jazz players use that tone. Can get more conventional 'Pop' bring down Highs to flat and boost upper midrange [800 on Markbass.]
 
Last edited:
  • Like
Reactions: SJan3 and TN WOODMAN
#11
PS; If knowing your tweeter 'Hisses' is unbearable and annoy's you to no end. This may be best solution [easiest also]

"Unscrew the speaker and you get access to the 'crossover' such as it is. The first set of wires are labelled 'input'. Pull the spades off the connectors and attach them to the speaker and put the wires from the speaker on to the connectors on the crossover. It isolates the tweeter and the crossover and you get the amps full output to the speaker."

Then you will have A CMD 121, NY 121, CMD 102 Etc. Jeff Berlin Model:)
 
#13
BassmanPaul said:
Wow! You must be stuck at home with nothing to do 'cos of the Pandemic!!

The OP was last here on December 23 2019. The poster before you was last here on April 01 2020.

Zombie alert!
Click to expand...

:) Nah to pandemic homebody but Bored possibly. Just wanted a space/spot for those whom are bombarded with this Hissing tweeter stuff to have an alternative Point of View when Goggling. [Most recent I could find]

And give them a chance to see 'The Forest for the Tree's
 
  • Like
Reactions: BassmanPaul and SJan3
#14
Being a tad older 'n' you I don't hear any hiss unless I have my hearing aids on. :(

As you get older you'll hear less and less hiss. It's part of the damn misnamed 'Golden Years.' Rusty years would have been better! :rollno:

All high gain electronics, tube or transistor, produce hiss. it's the price we pay for that gain. I get zero hiss through the tweeters in my Acme B2s but then again I designed the tube preamp with just enough gain to drive my power amp fully.
 
  • Like
Reactions: SJan3 and NEBADON2000
#15
Also, it's pretty easy to damage those Le Son tweeters. I've seen many NY121s with dead Piezo Tweeters. They don't really fizzle out and smoke, they just stop working completely, and because they're isolated and Piezo, they don't seem to affect the load on the amplifier...

It didn't help that the amplifiers commonly feed those speakers had a treble control centred around 10k. That's incredibly high and invites misuse to the point where the amp will hiss gleefully into those piezos.

I used to see NY121s hit the used market and many had perfectly fine woofers and blown tweeters. Luckily mine still works - and I don't find it hissy - it's just really harsh and really don't positively contribute to the sound of the cabinet. Same thing with the Markbass tweeter "add-on" they had originally... It was basically a piezo tweeter in a box the size of a Rubik's Cube.
 
#16
Im Late I know, just my fifty cents, also coming from experience with a Markbass Alain Caron combo which is basically an active speaker with a bass Pre and hissing plus some experience with building speakers with high efficiency drivers including compression drivers.
Yes, horns don’t his, but these here sometimes do. That’s simply because something in the soundchain causes it, as the poster described it’s not the bass, same for me,
It will be either the power amp itself, as there are some designs out there which hiss too much, which gets kinda obvious when you try them running idle on a horn doing 115dB in 1 Watt. So it must be wither in the power amp itself - mine has a separate one for the tweeter, so that’s my suspect, or even the pre itself.
When turning down the highs helps it is the preamp, as you don’t do anything to the poweramp by adjusting EQs.
I like my amp, too, and this would not be an issue if I either play loud or let the tweeter tweet nicely to my kneecaps having standing plain and not angled on the floor, but that wasn’t the purpose in the first place.
Best solution would be (hint to myself) to get that to Markbass service and have it fixed.
As there is not a general problem with the amps as far as I know, this must be a hopefully rare exception of misfunction.
 

Latest posts

Top Bottom
Back