SVT4PRO feels weaker.:FIXED bad cable

[JonathanD]

I love my amp, and I'm not looking to get a new one. But I have often thought that it doesn't put out as much power as it says it does. I can be riding the limiter and pushing "490" into each 210 can still not be heard unless I drop the low end and get a more flat tone. A couple people have said the same thing on other forums. Anyone have any experiance with this amp or other thoughts on it. Also, does anyone know how I can test to see what wattage it pushs.

 

one more thing, ah ah ah. Could someone direct me to a "how to change pre amp tubes" thread. Is it as simple as... Remove the cover, pull out old tubes, put in new tubes? With power amps there is Bias right, but not with preamp. I know not to touch them with my oily hands, I have gloves.

P.S. I plan to leave it plugged in to make sure they go in correctly;)

 

Jonathan

[Phil W]

I'm not very knowledgable about gear and tech issues. I'm sure you'l get better responses. From what I do know, though, the relationship between wattage and volume is not as straightforward as people believe.

[JonathanD]

I know what you mean Phil. The cabs have a lot to do with it, as does the gain level and the average signal level.

Maybe I should add that my power amp seems louder and is about the same wattage rating.

Jonathan

[jcadmus]

It may be the cabs you're using -- what are they?

 

It could also be the room(s)you're playing in. Is it a consistent issue, or does it vary from place to place?

[Big Daddy from Motown]

DO NOT change tubes with the amp plugged in or turned on.

That would be an excellent way to damage the tube and the amp.

 

Pre amp tubes can be simply removed and carefully replaced. No concerns about biasing.

 

You don't have to use gloves(that for halogen head light bulbs for your car)

 

Power is weird no matter how many times you explain it people just don't get it.

 

If you have a bass amp and you add another amp you have just added 3 DB, just a noticeable change, not twice as loud.

 

To be twice as loud you need 10 times as much power.

 

You cannot hear the difference between a 300 watt and a 400 watt amplifier.

 

I worked as a audio technician for years and every name brand amp I ever worked on (except for SVT tube amps) would produce it's rated output or more. Especially SWR amps by the way.

[getz out]

Tubes (especially preamp tubes) do not get hot enough to make hand oil a problem.

[JonathanD]

BDfM, I was joking about keeping it on:) and I understand that it takes 8-10 dB for most people to think its 2X as loud, and 3 dB takes 2X the watts, but something seems very off. I think my old TNT 150 would put this thing in the dirt.

 

Cabs, Eden D210XST and Ampeg BXT210M both at 4ohms and ran on each side in stereo.

Jonathan

[rumpelstiltskin.]

I can be riding the limiter and pushing "490" into each 210 can still not be heard unless I drop the low end and get a more flat tone.

 

you have answered your own question and do not even realize it!

 

you are trying to put a lot of low end into cabs that almost certainly can't reproduce the low end. so most of the power your amp is sourcing is being wasted and not turned into volume.

 

but supposing your cabs can reproduce the low end, you're still spending a lot of power on frequencies that require a lot of power in order to be heard. the result is that you're not using a lot of power on frequencies that *can* be heard, which means you *aren't* being heard.

 

if you like a really bassy tone that overpowers everything, there is no substitute for more and bigger cabinets.

 

robb.

[JonathanD]

Thanks robb.

I dont want to overpower at all, I want to lay at the bottom somtimes but still have presence. The eden 210XST is the lowest reaching Eden cab there is, at I think 32hz(-3) even if it is at 40 hz (-3) that is still a tone lower than any 810, 115, 215, 212, or 118 I know of for bass. Maybe I will give you a sound clip here shortly so you can hear what tone I am working at. I feel like there is no low end, The guitars have more lows than I do!!! when I wear ear plug I keep hearing bass notes that I;m not playing only to realize its the guitar player.(thats a whole different issue.)

Jonathan

[getz out]

Didn't you have issues with the Eden 210XST? Are you sure it is wired correctly? Sounds like it could be out of phase.

[yourlord]

I only played through a SVT4Pro once back in 2000 when I was on the market for my current rig. The SVT4Pro I tested was running into an 810 cab and would almost blow you off your feet.

 

That's all I have to offer.

 

 

EDIT: getz has a very good point. If this is the same cab you had that torn speaker in, and you wired it backwards, the speakers would be canceling each other out. Especially in the low end.

[alexclaber]

Didn't you have issues with the Eden 210XST? Are you sure it is wired correctly? Sounds like it could be out of phase.

 

Indeed.

 

Alex

[JonathanD]

Yes, I thought about this also, so I put a very lowered pitch(.5HZ) into the cab and watched the speakers moce, they move togehter. Also I ahve played this with the AMpeg 410HLF and BXT210M with the same results. I feel like I have tried all the room ideas I ave heard here. I did try standing about 40 feet away from the band last night and things did sound a lot more balanced. I have the cabs stacked so the Eden is vertical and the ampeg is on top in the horizontal plane. I will try tilting the ampeg back while on the Eden and setting my amp on the side and see if that helps any. Thanks, Jonathan

AMP

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[JonathanD]

In retrospect, it didn't always use to be this way. I am going to change the tubes and see what happens, and I am going to change strings agains soon(shouldnt mattter, but it is like a little happy birthday to me) and I am going to shorten the 15 foot cables I use to go from the amp to the cabs. I will have to order some speakons today nad get on that. I forget the formula, but I know that even 12 guage cables lose something at distance. Also, when power cables lay over themselves does that cause any interferance?

Jonathan

[getz out]

so I put a very lowered pitch(.5HZ) into the cab and watched the speakers moce, they move togehter.

 

0.5 Hertz? I am sure you made a whale cry somewhere. I am not even going to ask how you managed that.

 

How how do you know "it didn't always use to be this way"? I thought you just received that Eden 210XST.

[JonathanD]

Getz76,

Before I traded in the 410 for the 210 it seemed to be doing the same thing. The speakers were not moving in the cab and I could crank it in a 8X10 room and not shake things in the room. Where as with my old beat up TNT150 I could rattle something without pushing it. That is of course an exageration, but it hopefully gets across the idea.

 

 

 

.5HZ can easily be accomplished by using Logic and slowing the pitch and speed of something down untill it is rediculously low. .5 is what the program said it was going down to.

 

I couldnt hear anything, but the speakers move back and forths slowly.

Jonathan

[getz out]

Before I traded in the 410 for the 210 it seemed to be doing the same thing. The speakers were not moving in the cab and I could crank it in a 8X10 room and not shake things in the room. Where as with my old beat up TNT150 I could rattle something without pushing it. That is of course an exageration, but it hopefully gets across the idea.

 

I confused. I thought you said "it didn't always use to be this way", but now you are suggesting that it was this way. Which way is it and which was was it? The way it was or the way it is?

 

.5HZ can easily be accomplished by using Logic and slowing the pitch and speed of something down untill it is rediculously low. .5 is what the program said it was going down to.

 

I couldnt hear anything, but the speakers move back and forths slowly.

 

I understand how to reproduce such a thing, but I was wondering how you got it into the cabinet. Using what amplifier... and why would you do such a thing. Grab an alkaline battery next time, it's a lot easier to deal with and safer for your woofers.

[JonathanD]

Sorry about the confusion. I feel like I noticed this around last august. In retrospect, This may be one of the reasons I traded in the 410. Besides looking for something more compact and lighter I played a D210XST at a music store through an SVT4 (not mine) an the disparity was huge. The 210 and a bigger bottom without being loose and muddy.

 

It is possible, even probable that this is in my head. Ya know, I haven't checked the bridge stereo switch in a long time, maybe I hit it at some point... but i don't think this would be the symptom. And that switch is really far back there. Now that I am thinking about the back of the amp maybe should take a look at its set up and see if I have something amiss in the effects loop/crossover sections.

 

 

As far as getting the .5 into the cab I don't know what an amp can do. I used my SPA1600 to do it. maybe it was just putting overtones through... still slow enough to see.

BTW thanks for the battery idea... I'm guessing you use a 9 volt?

That may prove handy some day.

[_Sweet Willie_]

What kind of bass do you have?

 

Is it active or passive electronics?

 

If it's active, change your batter(ies). A dying battery can cause both distorted sound and lower volume.

 

Also, what are the settings on your bass? Do you have the volume turned all the way up? Please do. And zero out your EQ (if an active preamp is in the bass) while you troubleshoot this problem.

 

Peace.

--Dub $$

 

[JonathanD]

Schecter elite5 Active everything full up.

G&L tribute L2500 everything full up.

I will check the batteries anyway, but I dont think that is it because I still get the clip light for the preamp to hit as per usual.

 

thanks though...

Now to do laundry(have to go to the LandROmat), then to do check the back.

 

What kind of bass do you have?

 

Is it active or passive electronics?

 

If it's active, change your batter(ies). A dying battery can cause both distorted sound and lower volume.

 

Also, what are the settings on your bass? Do you have the volume turned all the way up? Please do. And zero out your EQ (if an active preamp is in the bass) while you troubleshoot this problem.

 

Peace.

--Dub $$

[getz out]

As far as getting the .5 into the cab I don't know what an amp can do. I used my SPA1600 to do it. maybe it was just putting overtones through...

 

I bet, since your power amp has a 20Hz to 20kHz response (+/- 0.5dB).

[jcadmus]

Okay, odd thought here, but are you sure the CABs are not out of phase with one another?

 

I know you said the speakers in the Eden cab are in phase.

 

[alexclaber]

Schecter elite5 Active everything full up.

G&L tribute L2500 everything full up.

 

Do you really mean all the knobs to max?

 

Alex

[JonathanD]

Okay, odd thought here, but are you sure the CABs are not out of phase with one another?

 

I know you said the speakers in the Eden cab are in phase.

 

I don't know, How would I test this. I guess tis possible since I wired the cables!!! I guess I could listen to them separately. Any suggestions.

[JonathanD]

Schecter elite5 Active everything full up.

G&L tribute L2500 everything full up.

 

Do you really mean all the knobs to max?

 

Alex

 

Yes, its about the only way I can make sure that they are in the same place for each test. its not a bad sound either.

Jonathan

[getz out]

Any suggestions.

 

Based on your responses to this thread, I would suggest you take the cabinets and amp to someone who has a clue on how to identify any problems.

[yourlord]

I don't know, How would I test this. I guess tis possible since I wired the cables!!! I guess I could listen to them separately. Any suggestions.

 

Whatever you used to generate that .5Hz sine wave will work through the amp, Just feed it a very low frequency signal (3-5Hz)and watch the drivers in both cabs.. if they move in opposite directions then they are out of phase.. All drivers should move in unison.

[Rocky McDougall]

What getz76 said !

[...]

Also I ahve played this with the AMpeg 410HLF and BXT210M with the same results.

 

Did you mean running the .5Hz tone through them and watching the speakers move or did you mean that setup doesn't give you enough low end/volume?

 

I can't stand the Ampeg HLF cabs because they have way too much booty. If you're not getting the desired effect from that head and a 410HLF cab there is something seriously wrong in your basic setup. An SVT4 Pro + 410HLF can destroy a building.

[...]

I don't know, How would I test this. I guess tis possible since I wired the cables!!! I guess I could listen to them separately. Any suggestions.

 

Whatever you used to generate that .5Hz sine wave will work through the amp, Just feed it a very low frequency signal (3-5Hz)and watch the drivers in both cabs.. if they move in opposite directions then they are out of phase.. All drivers should move in unison.

 

What he said.