noise/hum question about the sp-404sx

[forest]

It's probably circuit noise. The headphone out probably has its own circuitry, the line out usually is jacked on the whole shit, so, circuit noise. Do you use the 404 way close to the energy on the wall? This can cause circuit noise too.

Grounding it could help, someone certainly had already solved this and the answer is on some forum somewhere lol.

Oh, I just remembered. I don't know how is the energy service in your country and how stuff is made on your houses, but here in Brazil this is usually very poorly made. I do not understand much about it, but when energy comes and it's not properly grounded and balanced it will make music equipment hum.

[zindan]

i noticed that for the different values displayed on the bpm/value it makes different levels of hum or slightly different sound??? why???? wtf is this shit bruh i don't like this

why doesn't it hum with ext source? why doesn't it hum when no value is shown?

someone smart explain this and fix it pls PLS

[Sharris]

Hmmm...... I wasn't tryin to exaggerate when stating my sx is crystal clear.... If I turn the volume up really high I guess I can hear a little air....white noise maybe? But it's really minor.

Even when I make beats in other samplers, EVERYTHING ends up on my 404sx. & when listening to the beat prior to putting the sx in the signal chain, it sounds the same.

I HAVE noticed that my beats are a lot quieter than other people's beats. If the sx is at the end of the signal chain, since it has a low noise floor I can only get my beats so loud (at least I think that's the issue).

What you guys are talkin about sounds like there's something wrong with your unit.

[zindan]

BUMP

someone PLEASE HELP

[forest]

I HAVE noticed that my beats are a lot quieter than other people's beats. If the sx is at the end of the signal chain, since it has a low noise floor I can only get my beats so loud (at least I think that's the issue).

What you guys are talkin about sounds like there's something wrong with your unit.

Ungrounded circuitry hums, that is a fact. If I'm not monstrously wrong, Sharris' 404 has minus "natural" volume gain and that makes the hum and white-noise less noticeable.

i noticed that for the different values displayed on the bpm/value it makes different levels of hum or slightly different sound??? why???? wtf is this shit bruh i don't like this

When you change the display numbers, you change the energy passing through since more lights on need more resistors and shit being "active". The energy running through the positive and the negative side on the circuitry will be different and it will affect the hum for sure, nothing really weird here.

why doesn't it hum with ext source? why doesn't it hum when no value is shown?

Maybe they have something designed to just cut the signal when not is showing up? Very common too. Is this hum something like a p10 cable plugged on an amp? You know, when you touch the point of your finger on the other end, makes a hum too. That's ungrounded noise, since you aren't grounded - and sometimes if your house electricity isn't grounded and you are barefoot the shit will give you a significant electrical shock. - My point is, there is some component running loose there lol.

Maybe the broken one is Sharris' 404, since a bunch of people already talked about it online but sorry, Zendan, I didn't find anything on my 30 minutes research here. What you can do is open that, clean it with circuitry cleaner and put some circuitry lubricant (I don't know the English words for both of these). Also, again, check if your stuff is grounded and maybe try to test yours with a different power supply.

[zindan]

Ungrounded circuitry hums, that is a fact. If I'm not monstrously wrong, Sharris' 404 has minus "natural" volume gain and that makes the hum and white-noise less noticeable.

i noticed that for the different values displayed on the bpm/value it makes different levels of hum or slightly different sound??? why???? wtf is this shit bruh i don't like this

When you change the display numbers, you change the energy passing through since more lights on need more resistors and shit being "active". The energy running through the positive and the negative side on the circuitry will be different and it will affect the hum for sure, nothing really weird here.

why doesn't it hum with ext source? why doesn't it hum when no value is shown?

Maybe they have something designed to just cut the signal when not is showing up? Very common too. Is this hum something like a p10 cable plugged on an amp? You know, when you touch the point of your finger on the other end, makes a hum too. That's ungrounded noise, since you aren't grounded - and sometimes if your house electricity isn't grounded and you are barefoot the shit will give you a significant electrical shock. - My point is, there is some component running loose there lol.

Maybe the broken one is Sharris' 404, since a bunch of people already talked about it online but sorry, Zendan, I didn't find anything on my 30 minutes research here. What you can do is open that, clean it with circuitry cleaner and put some circuitry lubricant (I don't know the English words for both of these). Also, again, check if your stuff is grounded and maybe try to test yours with a different power supply.

thank you for your help

[BlitzKrieger]

You guys. Embrace the humming!

[ghost bazz]

I recently recorded some beats into my 808 w my Sampletrak plugged into the mic input on my mixer... I think I did it initially because I wanted to throw the mic effects onto it... but damn, so much noise! I had someone tell me that they liked the VHS effect! I was like, “Oh? Yeah totally.”

[Sharris]

If I'm not monstrously wrong, Sharris' 404 has minus "natural" volume gain and that makes the hum and white-noise less noticeable.

When you say natural volume gain.....are you referring to the gain settings on the 404? Reading your reply I thought about it & I haven't messed with the gain setting on my sx since I got it......that would make so much sense..... I bet my gain setting is low & that's why I don't hear any white noise & why my beats are quiet.

I'm going to turn up the gain & hear what happens.

[forest]

I was just thinking about the circuitry part of the SP that amplifies the signal (I don't have the knowledge to say anything about that though lol), if something is worn out, the gain could suffer from it generating a weaker (on volume) signal.

Since you have a bunch of amazing sounding gear and the SP is at the end of your chain, I bet the signal gets there hot already, so, you demand little from the SP gain.

[Sharris]

Since you have a bunch of amazing sounding gear and the SP is at the end of your chain, I bet the signal gets there hot already, so, you demand little from the SP gain.

The input gain on my sx isn't really needed? I think that's what you mean......... when I make beats on the sx.... turntable/synth/instrument goes thru a DJ mixer, to a Yamaha mixer, to Analog Heat to the sx. So that would make sense, it's already comin in hot, no gain needed.

But what about output gain? I was thinking that would make the difference with boosting levels OUT of the sx.

[Crane]

Grounding it could help, someone certainly had already solved this and the answer is on some forum somewhere lol.

Here you go.

https://www.mpc-forums.com/viewtopic.php?f=26&t=185081

Replacing the cheap ass/mass produced capacitors should help for hum and as forest mentioned, check the grounding points, and test with both batteries and your power supply.

Also, the gain on the SX is only two settings 0db and -10db. The control knob is only adjusting the the monitoring not the recording gain. All input needs to be adjusted through the incoming machine, mixer etc, and balanced between the two settings of -10db or 0db.
The original 404 does have "input gain" which can be adjusted by the control knob. So for people coming from the 404, 303 etc expecting and thinking it works the same can be confusing.

I think this thread has two separate issues intertwined, one being hardware hum and one being hum from the wrong selection of 0db vs -10db and using the control knob as a false gain.

[zukken]

If anyone decides to go forward with replacing capacitors in an attempt to resolve this humming symptom here is a helpful trick for quickly removing the type of capacitors you'd be working with. It will give you more working space and keep nasty plastic-melting heat away from the connectors in the general area you'd likely be focusing on. Flux is your friend whenever you're soldering (Amtech NC-559 or any similar non-tacky flux should do the trick) but if you're using it make sure to clean up with 90% isopropyl and cotton swaps when you're done as it is *mildly* conductive and can cause weird symptoms.

https://www.youtube.com/watch?v=rEhYVyXYU9c

[zindan]

I recently recorded some beats into my 808 w my Sampletrak plugged into the mic input on my mixer... I think I did it initially because I wanted to throw the mic effects onto it... but damn, so much noise! I had someone tell me that they liked the VHS effect! I was like, “Oh? Yeah totally.”

gotta make sure you have the volume level of your mic in and the level of whatever you're inputting at good levels. if u got the mic in turned up too much and whatever you're sampling turned down too much, you're going to get a dick ton of noise