Crate Blue Voodoo

[Ewizard]

While the SLM ( Crates parent Company ) is a USA based company, many things were made in other countries. I don't believe mine was a USA-made amp. Mine was the second rendition of it with plain text ( not the splashed text of the original release ). The mirror in the back was literally a piece of mylar stapled to the back panel. The tube glow was just 6volt light bulbs with a rubber cover to give them the orange glow.

The parts inside the amp were of decent quality, but the pots were the cheap PCB mounted 16mm type that had press-on knobs. As for the heater issue I had, it appears to be a bad trace & cold solder all in one. I eventually had to hotwire it. It was good all the way up to the little bulbs, but somewhere between them and the tube, it was intermittent. The amplifier all-in-all was good but just didn't have " IT ". When I converted it to a more JCM-800 it was certainly more fun, but it just wasn't either of those amps at that point.

I came across a couple of others over the years and got to play them, and it just reaffirmed my reason for offloading it. They had a sound, it just wasn't the one I had in my head. Looking back on the amplifier circuit, I can say that it was an original enough design. SLM really tried to make something that was along the vein of a Mesa with cascaded gain stages biased hot and cold. The issue I think was the tone control was at the end of the circuit, which made it less functional. They used vactrols for channel switching which stole some tone I think. The amp was also very bright and noisy. To control the gain they had to use lots of interstage grid leaks and grid stoppers. And they used an especially small coupling cap ( a .001 ) between the first stage and the second stage to control the bass. The cascading gain was clever, but I think what led to the fizzy, bee's in a can sound, was using two stages in a row with fairly high plate resistor values. Most amps do cold, hot, cold, etc. for gain staging. The BV went cold, hot, hot, cold and the two hot stages in a row really brought the beans to the distortion factory. There was a vactrol on each side of the distortion channel, so there were two opportunities to rob tone with the things. Between the noise ( lots of hiss ) and less than stellar channel switching design, it just isn't a top-tier amp.

 

[Ewizard]

In most amps, the area that is most often skimped on is the capacitors. Most amps made in foreign countries MUST conform to CE, RoHS, and other governing organizations and certifications in order to be sold worldwide as they are. So the design itself is usually over-engineered actually. Where the problems arise is where the pennies can be pinched. The most expensive small parts in an amp are capacitors. If you can save two dollars by going with cheaper parts, why wouldn't you? Especially when you can save $2 for every amp over thousands of amplifiers! Even a few cents can make a huge difference over thousands of amps.

Another big issue for modern production amps is the solder used. Leaded solder is now banned in almost all production. Lead-free solder is not as good as your run-of-the-mill Kester 44 Flux-core Pb solder. PCB parts that are wave, or flow soldered, can't use Pb solder. Lead-free solder is more prone to cold solder joints and vibration related failures.

PCB is inferior to turret board and PTP for that reason alone. When a PCB amp is working, they are no different, until something breaks. And they are more prone to breaking. That's all, nothing more, nothing less. $$$ is the determining factor in that difference. Hand-made PTP amps cost lots more to make. Amps like Two Rock which utilize PCB construction upset me a bit. They charge a premium price for something that can become problematic in the future. Mesa for example has gotten a lot of flack from their PCB designs. It's no wonder why amp repair technicians love working on older amps, because you can actually work on them.

 

[Top-L]

I watched a repair vid on youtube on this amp and it didnt look any worse than mid 90s pv quality. Actually liked the sound too!

Being honest, when that amp came out i wanted one! But i was almost literally a starving college student. Marty friedman endorsement! Purple! Whats not to like!?

When ppl started calling it blue doo doo., i figured that was just some clever word play, not any indication of its actual quality.

If i could find one that i was sure didnt need every capacitor replaced i would buy it.

 

[ErikH]

While the SLM ( Crates parent Company ) is a USA based company, many things were made in other countries. I don't believe mine was a USA-made amp. Mine was the second rendition of it with plain text ( not the splashed text of the original release ). The mirror in the back was literally a piece of mylar stapled to the back panel. The tube glow was just 6volt light bulbs with a rubber cover to give them the orange glow.

Mine was a first year. Got it straight from the SLM rep for the store I worked at then. Had the same mylar stapled on the back panel and the bulbs. A cool look for sure. Sounded good when it worked but damn, it was not reliable.

 

[Ewizard]

Mesa, huh? So is a Dual Rec like the Hot Rod Deluxe of high-gain amps?

If you look at a Mesa DR schematic and a Crate BV schematic, there are obvious differences. But when it comes to the brass tacks, the BV is a loose interpretation of a mesa. The major difference is the tone stack placement. In a Mesa, the tone stack is in between the first and second stages of gain. The BV has it at the end of the gain stages. There are a couple of other differences, but tit for tat, they are nearly the same idea, just rearranged.

I am not saying it is actually a Mesa, it just drew some inspiration from them. The BV does have what is essentially an original design, but let's be real, it had a target to hit.

 

[Top-L]

Mesa for example has gotten a lot of flack from their PCB designs. It's no wonder why amp repair technicians love working on older amps, because you can actually work on them.

This reminds me of an episode of "all amp/guitar techs are clowns" that happened about 15 years ago.

There was a supposed "amp technician" operating out of the back of a studio in Baltimore. Supposed good reputation. He was youngish guy, millenial, in his early 30s. (In retrospect probably not enough time for someone to develop the chops to really know what they are doing.)

I had bought a used JSX head six months prior that had developed buzzing in the power section. (I suspect it had started when previous owner unloaded it, but it got worse.)

Took it to the "amp tech" to diagnose and fix. Paid the bench fee ($150 if I remember). He said he fixed it after a week, but wasn't there when I went to pick it up. So I get it back home its doing the same damn thing. Another trip down town.... Sit down with him again to show him the symptoms.

He said "these are (eww) Peavey amps.. you don't expect them to be quiet? Its a high gain amp, expect it to have some noise." And he nice-guyed me out of the store with some pseudo promise that if a real problem developed, he would apply the bench fee to fixing it."

So I did some research on the web, at the time knew nothing about amp repair. Found some early videos online of amp noise and decided it was probably bad capacitors. Called PV and they were kind enough to put together an order for all the power caps ($60) and sent me a schematic. Told me which caps needed to be replaced.

I have alot of soldering experience, so a couple hours later, I replaced those caps and the amp went from a buzzing mess to DEAD QUIET.

The moral of this story?

The attitude of some amp techs that "PCB amps are an inferior waste of time", is a shield they can hide behind when they don't really know what's going on.

I would guess 98% of amps that someone wants repaired are PCB amps. Hopefully that "amp tech" figured this out the hard way and went back to being a barrista.

There are alot of advantages of PCB, namely that if you can read a schematic, everything is exactly where you expect it to be. I would not have been as confident in the repair if it was a "vaunted P2P" design.

 

[formula73]

This reminds me of an episode of "all amp/guitar techs are clowns" that happened about 15 years ago.

There was a supposed "amp technician" operating out of the back of a studio in Baltimore. Supposed good reputation. He was youngish guy, millenial, in his early 30s. (In retrospect probably not enough time for someone to develop the chops to really know what they are doing.)

I had bought a used JSX head six months prior that had developed buzzing in the power section. (I suspect it had started when previous owner unloaded it, but it got worse.)

Took it to the "amp tech" to diagnose and fix. Paid the bench fee ($150 if I remember). He said he fixed it after a week, but wasn't there when I went to pick it up. So I get it back home its doing the same damn thing. Another trip down town.... Sit down with him again to show him the symptoms.

He said "these are (eww) Peavey amps.. you don't expect them to be quiet? Its a high gain amp, expect it to have some noise." And he nice-guyed me out of the store with some pseudo promise that if a real problem developed, he would apply the bench fee to fixing it."

So I did some research on the web, at the time knew nothing about amp repair. Found some early videos online of amp noise and decided it was probably bad capacitors. Called PV and they were kind enough to put together an order for all the power caps ($60) and sent me a schematic. Told me which caps needed to be replaced.

I have alot of soldering experience, so a couple hours later, I replaced those caps and the amp went from a buzzing mess to DEAD QUIET.

The moral of this story?

The attitude of some amp techs that "PCB amps are an inferior waste of time", is a shield they can hide behind when they don't really know what's going on.

I would guess 98% of amps that someone wants repaired are PCB amps. Hopefully that "amp tech" figured this out the hard way and went back to being a barrista.

There are alot of advantages of PCB, namely that if you can read a schematic, everything is exactly where you expect it to be. I would not have been as confident in the repair if it was a "vaunted P2P" design.

I emded up dumping a nice-sounding Framus Cobra because nobody could diagnose an intermittent volume drop issue. The 2 owners after me tried and continued to have the same issues…

 

[LLL]

This reminds me of an episode of "all amp/guitar techs are clowns" that happened about 15 years ago.

There was a supposed "amp technician" operating out of the back of a studio in Baltimore. Supposed good reputation. He was youngish guy, millenial, in his early 30s. (In retrospect probably not enough time for someone to develop the chops to really know what they are doing.)

I had bought a used JSX head six months prior that had developed buzzing in the power section. (I suspect it had started when previous owner unloaded it, but it got worse.)

Took it to the "amp tech" to diagnose and fix. Paid the bench fee ($150 if I remember). He said he fixed it after a week, but wasn't there when I went to pick it up. So I get it back home its doing the same damn thing. Another trip down town.... Sit down with him again to show him the symptoms.

He said "these are (eww) Peavey amps.. you don't expect them to be quiet? Its a high gain amp, expect it to have some noise." And he nice-guyed me out of the store with some pseudo promise that if a real problem developed, he would apply the bench fee to fixing it."

So I did some research on the web, at the time knew nothing about amp repair. Found some early videos online of amp noise and decided it was probably bad capacitors. Called PV and they were kind enough to put together an order for all the power caps ($60) and sent me a schematic. Told me which caps needed to be replaced.

I have alot of soldering experience, so a couple hours later, I replaced those caps and the amp went from a buzzing mess to DEAD QUIET.

The moral of this story?

The attitude of some amp techs that "PCB amps are an inferior waste of time", is a shield they can hide behind when they don't really know what's going on.

I would guess 98% of amps that someone wants repaired are PCB amps. Hopefully that "amp tech" figured this out the hard way and went back to being a barrista.

There are alot of advantages of PCB, namely that if you can read a schematic, everything is exactly where you expect it to be. I would not have been as confident in the repair if it was a "vaunted P2P" design.

The world is your oyster when you learn and then DIY.

And amps with turret boards (usually called "hand-wired") are much easier to work on than PCB.

 

[Top-L]

The world is your oyster when you learn and then DIY.

And amps with turret boards (usually called "hand-wired") are much easier to work on than PCB.

But, working on PCB.. not exactly hard, is it?

 

[ErikH]

But, working on PCB.. not exactly hard, is it?

As long as you don't overheat the solder pads and/or lift one. When that happens, then you need to bypass the trace to the next pad and put a wire between the two so there is connection. And usually when working on a PCB in an amp, you have to remove the thing to do anything with it when it comes to replacing the components. With a PTP / turret board amp, you simply remove the chassis and get to work. Everything is right there with easy access to work on. There are pros and cons to both but when it comes to simplicity of making changes/repair without removing darn near the entire amp from the chassis, PTP / turret board is the easier way to go.

 

[LLL]

But, working on PCB.. not exactly hard, is it?

Have to be more careful. could lift a trace. plus the components can be smaller in size. And many times have to get underneath the PCB to remove components; not so typically with turret board.

 

[formula73]

Interesting. Does it sound anything like a Dual Rectifier?

Not in the slightest.

 

[Ewizard]

I Need to correct myself. My memory failed me. The Mesa DR does not have its tone stack between the first and second gain stage. It is at the end of the gain stages but is cathode follower driven. There is a Mesa design that does have the tone stack in between the first and second stages though. In either case, this does mean that the BV is trying very hard still to replicate the Mesa DR. The major difference in light of this new data is that the tone stack of the BV does NOT have a cathode follower driven tone stack, while the Mesa DR does. This does create a significant difference in sound. I do not like cathode followers.

Again, there are other small differences that lead to the difference in sound, the most significant is still the tone stack design and how it is driven.

 

[Top-L]

So trying, but failing spectacularly?

https://www.youtube.com/watch?v=OLV3eGgI5F8

Watch the whole thing to the end where he demos it. I really like the sounds he's getting.

I can't say if this is better/worse than other usa tube amps from that era. But if I found one in great shape at a reasonable price I would check it out. OTH, for same price could probably get a Bugera with a warranty.