Crate Music - Page 9 - Recent Questions, Troubleshooting & Support

This is a warm up issue and can probably best be found by using circuit cooler on suspected components.

Other possible problems may be a bad solder joint or cracked circuit board.

Candle the board with a bright light to look for cracks.

Bad solder joints take experience to spot, but pay particular attention where panel mounted volume controls solder to the circuit board. Looking for the little ring around the solder menicus takes a sharp eye and good lighting. Resolder any suspected bad joints.

Crate FlexWave... | Answered on Jul 30, 2010

The sound circuit on your system is like this:
1 = on guitar : pickup - signal potentiometer - signal tone potentiometer - plug. Simple test : plug the guitar in another amplifier to test it.
2 = on your amplifier : plug - preamplifier - volume control - reverb system - final amplifier. Since you get a good volume otherwise then the problem is before the final amplifier. Start by checking the cable with an ohmmeter for breaks and replace it if necessary.To test the rest you must dismantle it and access the components: start by shorting the potentiometer (center plot/signal input to the signal output) - the volume should go to the max. Then check that the preamp is working by touching the input wire - the brum should be clearly audible. Finally check the power source, the voltage on one of its power rails might be down and the preamp might not be powered.

Crate FlexWave... | Answered on Jul 29, 2010

150 watts should be easily handled by four Peavey speakers in the connection you described.. If the Peavey's are 8 ohms, then your total load was 8 ohms for the series/parallel arrangement which is well within the 2 ohm drive capability of the Crate according to specs.

I question if you really mean the speakers were in series? This requires a special cable to do this. Now if you mean they were "daisy chained" like the amp went to one speaker and another cable connected that speaker to another, then you REALLY had ALL speakers in parallel electrically which would be at the 2 ohm low limit of the amp... In either case, with only 1/4 of the 150 Watts to each, the speakers should NOT have been damaged. The amp MAY have been damaged. Try each speaker individually at a REASONABLE level to test.

If you plug into the effects loop out jack,OFTEN the connection to the internal power amp is broken so you might have to arrange a special cable as a wye to go back into the power amp as well as your external amp. In any case pwere ALL interconnected amps, etc from the same power source/receptacle for system safety.

Crate FlexWave... | Answered on Jul 16, 2010

Hi. use this link to check for the schematics.


take care.

Crate FlexWave... | Answered on May 31, 2010

I can't be sure for the result at your area, but I have to tell you that whenever I rebuild speakers at technicians in Greece (that's my country), the results were not very good. They always worked but after some working period started to make strange noices. Especially if you are a mucisian and the amplifier is yourself, replace them.

In case of a problem or clarification, don't hesitate to post me a reply.
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Crate FlexWave... | Answered on May 10, 2010

if they are square cement power resistors they are probably 3-5 watt 300-500 ohm .... are there colored stripes on the resistors? those are probably grounding resistors, they usually are installed too close to the board, get real hot a bunch of times and then crack the solder welds. when you replace them bring up the height and make space under the resistor to keep it off of the board and put a little drop of silcone underneath to hold them in place.

Crate FlexWave... | Answered on May 08, 2010

When you are changing the DSP effect on the fly, static or noise is NORMAL !!! The DSP is changing the data and having to recalculate on the fly and doesn't mute itself while doing so which results in "garbage sounds out".

The bypass setting should NOT get any tone UNLESS you have feedback going on. If your guitar can "hear" the speakers in the amp, the strings can vibrate and get feedback going.

Unplug the guitar and see if high freq tone is still there on bypass. If the tone is in the musical range, then there is a problem if nothing is plugged in. If it is a VERY weak, very high frequency tone, this may be the digitizing noise from the DSP. On bypass, the audio is likely to still go through the DSP, just not be modified by it.

Crate FlexWave... | Answered on May 03, 2010

Power light means very little. If unit has a preamp output, plug a set of headphones into it and see if you can hear anythin going through. (it will be weak). If you can, the power amp section is bad. Take in for service.

Crate Music | Answered on Mar 29, 2010

NEVER use switch cleaner such as DeOxit on pots !!!!!

I have used CRC226 available at Home Depot electrical dept.

I SUSPECT that the resistance element in that pot is cracked. This is common if the knob sustained a hit. Replacing the pot is the only cure if the element is cracked.

Reviewing the schematic, ALL audio passes through the wiper on the HIGH tone pots. If the wiper is intermittent, so will be the sound.

If your unit is solid state amp, the pot looks like a 10K ohm LINEAR taper.
If you have a tube type, then the pot is a 250K ohm LINEAR.

Note that the other tone pots in the units are AUDIO tapers, but the high is a linear taper.

Get repair parts from either or

Crate Music | Answered on Mar 23, 2010

Looking over the schematic I see all sorts of poor design. The reverb is driven by IC TL072 chip and the output is received by the same.

This chip is supplied with +/- 15.5 volts UNREGULATED which is stupid! If you get a power surge, the IC will be destroyed. Myself I would put at least a shunt Zener regulator on these voltages. Use a 100 ohm resistor in series and Zeners to ground for both the plus an minus 15.5 lines.

First thing check those 15.5 volt... the plus is on C23 pos term and the neg is on C24 neg term.

They have a 1 meg resistor to ground from pin 3 of the chip to bias the + input of the chip. This is TOO big as the input leakage current can be too much. I would reduce this resistor to 220K and increase C22 to 0.0047 mfd.

Check the DC voltage at pin 1 of the chip (IC1). It should be VERY near zero.

The output buffer for the reverb has better design. Check for zero volts or very near it on pin 7 of the chip. Be careful not to short to pin 7 which is pos 15.5.

If either of the above tests show a voltage over 0.5 volts from ground, replace the TL072 chip as it is likely fried by power surge..

Since there is high voltage (320 volts) use great caution when working on this amp.

Crate Music | Answered on Mar 15, 2010

Perhaps you have a bad capacitor on your volume control?

You can get an ESR meter and test your exposed isolation caps for leakage? The have to be removed so unplug the unit if you are gonna do any work inside the cabinet.

Also, try a shorter or higher quality guitar cable. This will cut impedance between the pickups and the amp.

Good luck and be careful!

Crate FlexWave... | Answered on Mar 08, 2010

You have a broken solder joint. You'll have to disassemble the amp enough to get at the soldered side of the circuit board that the controls are mounted to and touch up any suspect solder joints. Just be sure to resolder only the joints that were originally soldered or need to be soldered. Hope this helps.

Crate FlexWave... | Answered on Mar 08, 2010

Check for bad tube... it HAPPENS that brand new ones fail... USUALLY if they last 50 hours, they will last for the expected life. The bad tube would likely NOT be the main power tubes, as the amp would still run on one cylinder...

Crate Music | Answered on Feb 02, 2010

I can understand your confusion... and a lot depends how you are going to use this. There are some caveats regarding the connections,
If you use the 1/4 outputs on the GSP, there is a speaker modeling like function that is NOT available, that IS available IF you use the XLR outputs.
The STP is an "Insert Snake" which is not really what you want as it is intended to send and receive (audio going both directions in the cable.
If you want that speaker function, then you should get two XLR to 1/4 TRS cables and go from the XLR's on the GSP to the Left and Right inputs on the back of the Crate. Your audio or guitar then is connected to the GSP guitar input.
If you connect the guitar to the crate and then use the STP, Plug the TRS single connector into the Left/Mono/send/rtn on the Crate. The Send cable of the Y should go to the Send jack on the back of the GSP and the return should go to the left return jack of the GSP. This connection I would NOT recommend as it will be noisier and you will lose the stereo effect capabiltiy since the effect is inserted as a mono.

I believe you would be happier with using the XLR's to carry left and right to the Crate and run your inout to the GSP. In short, you have the wrong cable to do the best job.

Crate Music | Answered on Jan 31, 2010

Do you happen to have another speaker that you could hook up to speaker output? This would bypass the amps internal speaker and lf you get sound from that setup, it would mean either a jack failure or possible internal speaker problems. Please let me know.

Crate Music | Answered on Jan 24, 2010

you have either a failing fuse or a failing power transformer. take out the screws on the top of the amp, leave the handle in tact and pull out the chasis. look at your fuse to see if it is in its holder correctly, and see if the fuse is burnt. the correct fuse values will be printed on the circuit board. if the fuse looks good then, it may be the power tranny going south.

Crate FlexWave... | Answered on Jan 21, 2010

its a crate. 60% of all crate amplifiers go back on defects. take the top screws out and slide out the chasis, look at the fuse and determine if its toast. if the fuse is good, get a new amp. if the fuse is bad replace it and you should be good. the circuit board will have the correct fuse to be used printed on the board.

Crate FlexWave... | Answered on Jan 21, 2010

did you change out the fuse? could be a tranny going south. if you change the fuse and you still get no power, then you have a fried power transformer. they are relatively easy to replace. look on ebay . get the numbers off of the existing one and start web searching. something will come up. if not email me on my contacts tab in my website we can troubleshoot. you should see the custom blue voodoo i built and gave to my little brother.

Crate Blackheart... | Answered on Jan 21, 2010

Do you have electronics experience? Inspect the amp for broken or cold solder joints and any burned components. Check to see if the fuse blew and that the output IC's or transistors (not sure what Crate used in these) are not bad. Check your speaker wire as well.

Crate FlexWave... | Answered on Jan 16, 2010

You can reach the limiting IRRESPECTIVE of where the volume control is set when you have a guitar or other source that has HIGH output.

Guitars that have battery in them with internal amplifiers are an example of a high output guitar. Plain inductive pickups may require the volume control to be set at say 70% to reach limiting.

Please NOTE that the volume control is NOT linear, but is an "audio taper".

Limiting means you are probably driving it too hard. Many learn the hard way when speakers and thee power amp fail.

When the cone is driven too far beyond the pole pieces of the magnet, then the IMPEDANCE of the speaker becomes relatively low and can damage the power amp. The limiter tries to prevent this by sensing the current and or voltage and will back off the gain internally. This causes distortion when it happens.

Crate Music | Answered on Dec 14, 2009

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