05' Ampeg Svt3-pro "Low Switch" Mud when DISengaged

[Travis_Bass]

I will start off my apologizing if this topic has been covered before, but I searched everywhere, and couldnt fine a direct answer to my problem. I run my Ampeg through a SVT-410hlf 4 ohm 500 wat Ported cabinet. I usually run with the Low switch pushed in, and sometimes one or both high switches pushed in too. My bass is set to 12:00, mid 2:30 and set to 4, trebel at 2:30 also. I have my gain at 7:00 ( 3/4) and master volume at 9:30 (10% power). I run tube gain at 12:00.

Problem: I get a very mid-heavy crap tone when I depress the Ultra Low switch (when it is disengaged). Is this normal? I have messed with the mids, and even cut the mids; tried everything. I find the Ultra Low switch cleans the tone up A LOT, and gets rid of the ringy mud tone. Now I have a few questions: Could this be caused by old / bad preamp tubes, or my bass (Ibanez SRA500 w/ Brand new Slinkies rounds)?

Thanks so much, this has been haunting me since day one.

[JimmyM]

can't remember how the ultra low switch works, whether it boosts lows or cuts highs, but when you disengage it, you absolutely should hear more mids.

[GMSweet]

You probably should grab a copy of the manual from the Ampeg site, but on the SVT3-Pro the Ultra Low does the following:

• +2.5dB @ 50hz
• -12dB @ 560hz
• +1.5dB @ 5khz

Basically, the button is a built in "smiley face" EQ. Depending on your bass and other components, this can help or hurt. My SVP-Pro is similar, but voiced differently (+3dB @ 40Hz, -12dB @ 500Hz). If the low button being engaged works for you, go with it. If you find yourself having a hard time being heard in a band situation, you may want to take it off, and then set the mid frequency selector to the second or third position (450hz or 800hz) and cut a bit less than 12dB out of the system.

I've never had the pleasure of running through a "real" full tube SVT, but I used to run my SVP-Pro into a PLX-2402 into a pair of 410HLFs and always ran the Ultra Low switch engaged. Depending on the room, I backed off the bass control to undo the bass boost.

I hope this helps,

Matt

[stiles72]

Originally Posted by Travis_Bass

Problem: I get a very mid-heavy crap tone when I depress the Ultra Low switch (when it is disengaged). Is this normal? I have messed with the mids, and even cut the mids; tried everything. I find the Ultra Low switch cleans the tone up A LOT, and gets rid of the ringy mud tone. .

Yes - very normal. As the manual info indicates, it bumps some lows, cuts some mids, and bumps some highs. That sound not be for everyone - hence why you hear a lot of folks say to not run the ultra lo engaed on Ampegs. I always use it on any that I run through. Even on the old SVT's and VR's, (probably the old B15's also) "Ultra Lo" is actually a cut @ 600hz rather than a low frequency boost. Just cleans things up a bit more.

[Travis_Bass]

it could be my bass that is making it sound bad, because ibanez basses are more mid / bassy than say a wal bass. Thanks for the help... I think the mud sound will go away in a live band setting.

[basswaggz]

I have the same setup, 3Pro & 410HLF. Now I use active Fenders but I also always leave my Ultra Lo feature engaged.

[Fuzzbass]

Originally Posted by basswaggz

I have the same setup, 3Pro & 410HLF. Now I use active Fenders but I also always leave my Ultra Lo feature engaged.

I've often used the Ultra Lo on the Ampeg gear I've owned. It can be especially useful with a mid-heavy bass and/or cabinet... but sometimes it's fun to engage Ultra Lo and then boost your favorite frequency on the Vari Mid.

[Travis_Bass]

Experimenting with the ultra low switch off, I noticed more clipping distortion coming from my amp. Ive posted about this before, and was concluded that it might be my eq. But no one has told me the preamp tubes are NOT part of the problem. This amp has been dropped (said the previous owner) and the tubes are original... and I can afford new tubes easily. Do you think new tubes would solve the clip distortion? I mean its not like im over pushing the amp, but any kind of bass or mid boost, makes the amp clip and sound bass when i dig into the strings.

[JimmyM]

Originally Posted by Travis_Bass

Experimenting with the ultra low switch off, I noticed more clipping distortion coming from my amp. Ive posted about this before, and was concluded that it might be my eq. But no one has told me the preamp tubes are NOT part of the problem. This amp has been dropped (said the previous owner) and the tubes are original... and I can afford new tubes easily. Do you think new tubes would solve the clip distortion? I mean its not like im over pushing the amp, but any kind of bass or mid boost, makes the amp clip and sound bass when i dig into the strings.

might be possible, but i think a more likely story would be that the mosfets need biasing.

[Travis_Bass]

Do you think that maybe I should take my amp into my music store and see what they say? The amp sounds great with the ultra low engaged, but loses its definition when depressed. Imagine going from a $500 pair of headphones, to a dollarstore radio. Not that extreme, but a loss of clean bass and highs.

[Travis_Bass]

Come to think of it, I think my amp is being normal. It sounds sort of like this clip
http://www.youtube.com/watch?v=Ysy4_...eature=related
Which can be used to sound awesome. I just didnt know it