I have a volume problem with going from a Peavey M-2600 into Seismic Audio FL-15P cabs.
The power amp is says 4 ohm minimum 130w rms 4 ohms and the speakers are 8ohm power rating 400 watts.
Years ago I used the M-2600 to power my guitar rack system to two 4*10 cabs stereo...
EXTREME VOLUME!
Now if I go from a Roland FA-06 into a board that uses the M-2600 as the power source I have very little volume...I mean you hear it but no where near the Guitar rig volume.
Even if I go from the stereo outs on the FA-06 directly into the Stereo inputs on the M-2600 I get low volume.
Is the power amp not able to power the Seismic Audio Monitors?....The FA-15P's?
Am I doing something wrong?
Can I do something to fix this?
I'm lost....
I also tried going from the FA-06 into a Korg D-3200 Standalone Deck two channels for Stereo and put the Monitor outs into the ins of the M-2600 and went to the cabs....Sickly low volume...
I'm only a hobbyist and far from a pro...
I'm 61 and I do this for the fun....No Genius here...But I love music and wish to resolve my problem somehow....
Do any of you Guys have an IDEA?
Please help me out.......
Frank
The power amp is says 4 ohm minimum 130w rms 4 ohms and the speakers are 8ohm power rating 400 watts.
Years ago I used the M-2600 to power my guitar rack system to two 4*10 cabs stereo...
EXTREME VOLUME!
Now if I go from a Roland FA-06 into a board that uses the M-2600 as the power source I have very little volume...I mean you hear it but no where near the Guitar rig volume.
Even if I go from the stereo outs on the FA-06 directly into the Stereo inputs on the M-2600 I get low volume.
Is the power amp not able to power the Seismic Audio Monitors?....The FA-15P's?
Am I doing something wrong?
Can I do something to fix this?
I'm lost....
I also tried going from the FA-06 into a Korg D-3200 Standalone Deck two channels for Stereo and put the Monitor outs into the ins of the M-2600 and went to the cabs....Sickly low volume...
I'm only a hobbyist and far from a pro...
I'm 61 and I do this for the fun....No Genius here...But I love music and wish to resolve my problem somehow....
Do any of you Guys have an IDEA?
Please help me out.......
Frank
90w/ch isn't a lot of power but PA speakers are usually pretty efficient.. same as a guitar cab normally.
You have the gains on the PV cranked all the way up?
Known good 1/4 cables between the keyboard and amp?
Are the SA cabs new? These are not high quality but if somebody swapped in car audio drivers they will need hundreds of watts to make any SPL.
You have the gains on the PV cranked all the way up?
Known good 1/4 cables between the keyboard and amp?
Are the SA cabs new? These are not high quality but if somebody swapped in car audio drivers they will need hundreds of watts to make any SPL.
New cables all the way around.
Yes the monitors were cheap but new...
The reviews were pretty good also.
I was just hoping it was a mismatch of something that I could fix..
The gain on everything I have cranked..
If I were to do that with the old guitar rig it would have squealed and whined...I always turned that on with the gains off...Well all the way down..
I'm hoping to get this figured out so I can buy other things...
I might have to get a new power amp if I can't get this working..
Frank
Yes the monitors were cheap but new...
The reviews were pretty good also.
I was just hoping it was a mismatch of something that I could fix..
The gain on everything I have cranked..
If I were to do that with the old guitar rig it would have squealed and whined...I always turned that on with the gains off...Well all the way down..
I'm hoping to get this figured out so I can buy other things...
I might have to get a new power amp if I can't get this working..
Frank
These amps are ancient. I just bought one. It is pretty soft. Speakers are new too,cost $2.50 @ salvation army resale, so I don't know yet. First check is AC voltage on speaker at maximum volume. Use an analog AC voltmeter, 50 vac scale. 130 W 4 ohms is 22.8 vac. Not getting that, the amp is at fault. Yes 22.8 v, the speaker is at fault. Cheap DVM will lie on music, RMS DVM costs too much, averages over 2 seconds, and ignores oscillations over 7 khz. Analog Ac voltmeter go as low as $30 for imports. I like my Simpson 266-XLPM, 1986 and no e-caps to go bad.
These M-2600 are old. Mine is 90's. Possible sources of low volume are dried up input cap, dried up rail caps, or dried up coupler cap. The transistors & resistors don't typically age, but are subject to meltdown if they ever touch a shorted wire or driver.
You can also check the signal going into the M-2600 with a Y cable to ensure that is 2 vac.
Edit: I just checked my M2600 turned all the way up and it is putting out 3/4 vac on an 8 ohm speaker. times to order some caps and take the cover off. Back to monaural. The MMA-81502 I just put new rail caps in is a lot louder.
These M-2600 are old. Mine is 90's. Possible sources of low volume are dried up input cap, dried up rail caps, or dried up coupler cap. The transistors & resistors don't typically age, but are subject to meltdown if they ever touch a shorted wire or driver.
You can also check the signal going into the M-2600 with a Y cable to ensure that is 2 vac.
Edit: I just checked my M2600 turned all the way up and it is putting out 3/4 vac on an 8 ohm speaker. times to order some caps and take the cover off. Back to monaural. The MMA-81502 I just put new rail caps in is a lot louder.
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Thanks for the advice....
I'm gonna take the Peavey to a guy in Waycross Ga.. He is a very brilliant Old Man..Audio his whole life and Loves a challenge like this...
I'll have him check out the 2600...
I will also continue to troubleshoot as was stated also...
I am going to also look into if I can increase the output level on my FA-06....I'm sure there is..
I might just order a new Power Amp also...
I'll get an 8ohm to match as stated above.
Any recommendations for a great budget Power Amp?
Thanks again for the replies..
Frank
I'm gonna take the Peavey to a guy in Waycross Ga.. He is a very brilliant Old Man..Audio his whole life and Loves a challenge like this...
I'll have him check out the 2600...
I will also continue to troubleshoot as was stated also...
I am going to also look into if I can increase the output level on my FA-06....I'm sure there is..
I might just order a new Power Amp also...
I'll get an 8ohm to match as stated above.
Any recommendations for a great budget Power Amp?
Thanks again for the replies..
Frank
Four 4700 uf @ 63v rail caps and two 2.2 uf @50NP input is <$20. Throw in six 22 uf @25 v for $3 and you have changed all the rubber sealed caps. Use safety glasses, solder splashes.
The device holding M-2600 to .1% HD instead of .03% of the CS800s is probably the TL074 op amps. Converting to ST33079 would probably push the HD down, but these may require 33 pf bypass capacitors around the feedback resistor to not oscillate. Peavey used NJM4560 or 4580 in the cs800s, but these are duals, not quads.
For new amps the pros on groupdiy.com were recommending hypex, nordacoustics uk and bryston. Who makes half decent power amps these days?
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M-2600 has only heat sinks, transformers two pairs output transistors for 140 w/ch 4 ohms. But with a cleaner more modern quad op amp than TL074, the .1% HD limitation should go away. drivers & VAS aren't that different, 30 mhz MJE15031/32. What I like about M-2600 for home use, no fan.
BTW if you want to work hard, was a CS800s on ebay yesterday for parts or repair, $30 & freight. Might be as simple as the 47 uf cap that shorted & burned a .160 ma fuse in my first unit. That unit was stolen, but the $204 replacement worked at arrival. Replaced 200 VDC mains caps and that 47 uf cap already. CS800s is a good amp for my performance ambitions, but I'd rather have a 140 w/ch amp without fan in my music room.
Older Cs-800 rev X can be a bargain with .03% HD but the 70 lb weight runs the shipping charge up. Can't be shipped by USPS. CS800 Rev A, B, C, are hissy at low volumes, need the 1980 741 op amp replaced by something quiet like a OPA604. Even a TL071 would be quieter.
On repairing your M2600 amp, electrolytic capacitors look like model railroad oil tanks. All except the NP have one terminal labeled "-' which has to be marked on the board before you pull them. Backwards, they explode. They are marked with size and voltage, as I quoted before. You replace 25 with 22, 5000 with 4700. I use the long service life caps, >3000 hours, from newark & digikey, as I don't want to do this 4 times as I did on my ST70 with TV parts store caps. The 4700 will be a "snap in " aluminum electrolytic, on a different page than the leaded small ones.
You'll need a soldering iron, I like parts-express vari-temp. I like the $3 PE solder sucker bulb. I like safety or reading glasses from dollartree. family dollar has needle nose plies. diagonal cutters are better from the fishing dept of a discount store, walmart or meijers. You need rosin core solder, 26 to 30 gauge. Newark or digikey have some, haven't tried PE's yet. You need a 6 way screwdriver. maybe a slip joint plier to hold nuts. That is it. Soldering tutorial on jameco.
Safety tip, don't use 2 hands if the unit has been recently been on. >24 volts across your heart can stop it. Touch no metal >10 vdc to speaker ground. Wear no jewelry on hands or neck, 1 vdc @ 30 amps through a ring can burn your flesh to charcoal.
BTW if you want to work hard, was a CS800s on ebay yesterday for parts or repair, $30 & freight. Might be as simple as the 47 uf cap that shorted & burned a .160 ma fuse in my first unit. That unit was stolen, but the $204 replacement worked at arrival. Replaced 200 VDC mains caps and that 47 uf cap already. CS800s is a good amp for my performance ambitions, but I'd rather have a 140 w/ch amp without fan in my music room.
Older Cs-800 rev X can be a bargain with .03% HD but the 70 lb weight runs the shipping charge up. Can't be shipped by USPS. CS800 Rev A, B, C, are hissy at low volumes, need the 1980 741 op amp replaced by something quiet like a OPA604. Even a TL071 would be quieter.
On repairing your M2600 amp, electrolytic capacitors look like model railroad oil tanks. All except the NP have one terminal labeled "-' which has to be marked on the board before you pull them. Backwards, they explode. They are marked with size and voltage, as I quoted before. You replace 25 with 22, 5000 with 4700. I use the long service life caps, >3000 hours, from newark & digikey, as I don't want to do this 4 times as I did on my ST70 with TV parts store caps. The 4700 will be a "snap in " aluminum electrolytic, on a different page than the leaded small ones.
You'll need a soldering iron, I like parts-express vari-temp. I like the $3 PE solder sucker bulb. I like safety or reading glasses from dollartree. family dollar has needle nose plies. diagonal cutters are better from the fishing dept of a discount store, walmart or meijers. You need rosin core solder, 26 to 30 gauge. Newark or digikey have some, haven't tried PE's yet. You need a 6 way screwdriver. maybe a slip joint plier to hold nuts. That is it. Soldering tutorial on jameco.
Safety tip, don't use 2 hands if the unit has been recently been on. >24 volts across your heart can stop it. Touch no metal >10 vdc to speaker ground. Wear no jewelry on hands or neck, 1 vdc @ 30 amps through a ring can burn your flesh to charcoal.
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Well, I increased the output of the FA-06 from 0 to +12db...
It works great...
I think all along it was the output of the FA wasn't enough...
Now it is.
And as Indianajo said........Quiet....
Plenty loud enough now in my little cool *** Home Studio.....
Thanks to all!
Man I have a MILLION questions!
LOL
Frank
Also Indianajo...
I'd love to do those upgrades to my PV if you talk me through it....
My email is in my profile....Would be cool....A little extra volume with a solid quiet PA
Frank
It works great...
I think all along it was the output of the FA wasn't enough...
Now it is.
And as Indianajo said........Quiet....
Plenty loud enough now in my little cool *** Home Studio.....
Thanks to all!
Man I have a MILLION questions!
LOL
Frank
Also Indianajo...
I'd love to do those upgrades to my PV if you talk me through it....
My email is in my profile....Would be cool....A little extra volume with a solid quiet PA
Frank
If your M-2600 produces enough voltage as it is, new capacitors won't help it. It is my M-2600 that is not putting out enough voltage.
One has to have really good speakers to tell the difference between .1% HD and .03% HD. Right now, after the burglary, I'm making do with vile speakers from the charity resale shop. I don't propose you start of changing the TL074 as your first electronic project. Changing a soldered in DIP IC requires fine soldering skills. Not the job for a beginner.
Picking up an analog voltmeter with 20 vac or 50 vac scale would be useful for determining in future whether your amp has a problem or not. They are about $30. $30 DVM won't do, they are only accurate on AC at 50 or 60 hz.
I arrived at the voltage 22.8 VAC as nominal full power into 4 ohms, by the formula V=sqrt(P*Z) where Z is speaker impedance, 4 or 8 ohms. P was 130 W from the Peavey spec sheet..
As the M-2600 is rated 75 watts into 8 ohms, sqrt 600 is 24.5 volts, the maximum that could be expected from an in spec unit on 8 ohm speaker.
Old amps that won't put out rated voltage on the speaker quite frequently have dried up electrolytic capacitors. These are sealed with rubber, and the water vaporizes after some years when the rubber cracks.
Be careful to not short the speaker leads while testing full output voltage with the probes, that would blow up the M-2600 output transistors. It is not protected against shorts, it is a budget amp.
Happy listening.
One has to have really good speakers to tell the difference between .1% HD and .03% HD. Right now, after the burglary, I'm making do with vile speakers from the charity resale shop. I don't propose you start of changing the TL074 as your first electronic project. Changing a soldered in DIP IC requires fine soldering skills. Not the job for a beginner.
Picking up an analog voltmeter with 20 vac or 50 vac scale would be useful for determining in future whether your amp has a problem or not. They are about $30. $30 DVM won't do, they are only accurate on AC at 50 or 60 hz.
I arrived at the voltage 22.8 VAC as nominal full power into 4 ohms, by the formula V=sqrt(P*Z) where Z is speaker impedance, 4 or 8 ohms. P was 130 W from the Peavey spec sheet..
As the M-2600 is rated 75 watts into 8 ohms, sqrt 600 is 24.5 volts, the maximum that could be expected from an in spec unit on 8 ohm speaker.
Old amps that won't put out rated voltage on the speaker quite frequently have dried up electrolytic capacitors. These are sealed with rubber, and the water vaporizes after some years when the rubber cracks.
Be careful to not short the speaker leads while testing full output voltage with the probes, that would blow up the M-2600 output transistors. It is not protected against shorts, it is a budget amp.
Happy listening.
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