Acoustic B600H Problems

[jmansourdumas]

FYI. I bought a used B600H a few years ago. It suddenly had no sound. The circuit boards had multiple bad solder joints. I don't know if Acoustic Amplification increased their inspection of PCB's (assumiming they're getting them from China), or generally their Quality Control. As a technician, that's not an uncommon problem with electronics. The boards are mass produced and are soldered through wave soldering. Wave soldering - Wikipedia, the free encyclopedia

 

[BassmanPaul]

Ha ha ha ha I zinged MYSELF!!!!! Looks like I'M the SLOW GUY TODAY!
Thank you Bass Pounder... I think I better have more coffee......

it’s OK! I just liked a @RickenBoogie post from 2009!! I don’t think I was this thick when I was 69!!

 

[agedhorse]

FYI. I bought a used B600H a few years ago. It suddenly had no sound. The circuit boards had multiple bad solder joints. I don't know if Acoustic Amplification increased their inspection of PCB's (assumiming they're getting them from China), or generally their Quality Control. As a technician, that's not an uncommon problem with electronics. The boards are mass produced and are soldered through wave soldering. Wave soldering - Wikipedia, the free encyclopedia

There is nothing wrong with wave soldering, and in fact when it is done correctly produces far superior joints to hand soldering. My personal experience is less than one failure per million soldered joints wave soldered with lead-free solder. I challenge anybody in the world to hand solder with that reliability rate.

 

[B-string]

There is nothing wrong with wave soldering, and in fact when it is done correctly produces far superior joints to hand soldering. My personal experience is less than one failure per million soldered joints wave soldered with lead-free solder. I challenge anybody in the world to hand solder with that reliability rate.

I tried to avoid that post for fear of another "superior" point to point handwired debate. We need those "superior days" when QC departments were half the size of production to handle the failure rate.

 

[jmansourdumas]

There is nothing wrong with wave soldering, and in fact when it is done correctly produces far superior joints to hand soldering. My personal experience is less than one failure per million soldered joints wave soldered with lead-free solder. I challenge anybody in the world to hand solder with that reliability rate.

I agree with you: "There is nothing wrong with wave soldering, and in fact when it is done correctly produces far superior joints to hand soldering. Emphisis in bold. I was curious and did a Google search on wave soldering defects and there are several articles that I thought were really interesting. I guess it just depends who makes the boards.

 

[B-string]

The chances of improper hand soldering are much greater than faulty wave solder. That was one of the driving factors in the development of wave soldering.

 

[agedhorse]

Crappy soldering is crappy soldering no matter how it's done. My point was that with equal quality processes, wave soldering can produce better AND more consistent low defect joints over the long haul.

 

[agedhorse]

member: 131501"]How does your company choose what board manufacturer to use?

All PCB assembly is done in-house in the US. It's part of the built in the USA commitment the company stands behind.

 

[jmansourdumas]

All PCB assembly is done in-house in the US. It's part of the built in the USA commitment the company stands behind.

And that's why Mesa Engineering is at the top of the list. Thanks for responding to my threads.

 

[Kirk Bryant]

That's why he's the man! Except when he's a horse, and we all know a horse is a horse of course of course unless the horse is Agedhorse!

 

[agedhorse]

Wilbur???

 

[pauly3styx]

The B600H is designed for 4 or 2 ohm loads. Perhaps putting an 8 ohm load is messing with things. Always go with what is labeled on the amp IMO.

 

[agedhorse]

The B600H is designed for 4 or 2 ohm loads. Perhaps putting an 8 ohm load is messing with things. Always go with what is labeled on the amp IMO.

C'mon, this is just crap. This amp delivers ~300 watts into 8 ohms and will do so without any issues.

 

[BadExample]

it’s OK! I just liked a @RickenBoogie post from 2009!! I don’t think I was this thick when I was 69!!

You have to get a zombie in the head or it just keeps coming back.

 

[jmansourdumas]

C'mon, this is just crap. This amp delivers ~300 watts into 8 ohms and will do so without any issues.

I think this is correct: The voltage rails are +/- 75V. Ohm's law states that power is equal to the voltage squared divided by the resistance of the load (for instantaneous power). (75/sqrt(2) = 53.03 VMRS; 53.03^2/8 = 351.52 W). The equivalent DC voltage necessary to deliver 351.52 watts to an 8 ohm load would be 53.03 volts!

Acoustic Amplification didn't publish that. Nor did they give me any technical support when it crapped out on me and C10 on the negative low voltage rail blew it's top. The -24V rail feeds the protect circuit between the circuit breaker and the power switch. The caps were 85 deg C so I replaced them with 105 deg C Rubycon caps and also replaced both the 10,000 uf 80V caps, also with Rubycon. The amp works great now. So, I thought I'd find a matching speaker cabinet. I found a Acoustic B115 MKII 1 x 15 cabinet and was told the driver made a little noise. For $50+S/H , it was a pretty good deal. I thought it wouldn't be too much to find out the OEM driver used and I was told they didn't have that information available. Again, I was on my own. So, I measured the inside of the cabinet for alignment (Vb) and decided to replace the driver with an Eminence Kappalite 3015LF. Although the cabinet used vented slots instead of ports, I was able to calculate the volume for comparison. Sounds very nice. Tight mids and plenty of low end to around 40hz.

So, considering the budget I had to work with, it turned out OK.

 

[agedhorse]

Nice resolution.

Sometimes parts are intolerant of marginal circuit design, I have certainly seen applications where the ratings were unintentional exceeded, even on a short term or transitory basis.

 

[jmansourdumas]

Nice resolution.

Sometimes parts are intolerant of marginal circuit design, I have certainly seen applications where the ratings were unintentional exceeded, even on a short term or transitory basis.

I don't even know who designs Acoustic amps or speaker cabs. No real technical support. I wonder if they sub out the designers. You wouldn't know about the 15" driver in the B115 MKII 1x15" cabinet. I think it's an Eminence but the label indicates "B400 8ohm 450W25". I can't find info on that anywhere and Acoustic Amplification doesn't give it out. The backplate is flat (no bump) and the only marking is the label on the side of the magnet.

 

[agedhorse]

An OEM Eminence part, replacements should be available from Acoustic.

 

[jmansourdumas]

An OEM Eminence part, replacements should be available from Acoustic.

Nope. No cigar. Acoustic has, by far, the worst technical support. I realize that driver is probably an OEM Eminence (Kind of looks like a Kappa 15A-American Series). I worked at M&K Sound before Ken filed Chapter 7. (Evidently, someone was building counterfeit M&K product. (Invalid Link Removed)) I used to talk with McJerry @ Eminence. Great guy. He said it was probably an Eminence OEM driver. However, it is totally at the discretion of the OEM product manufacturer to support replacement/recone kits for their products. So, I'll never know but not a problem; that Kappalite 3015LF is an awesome replacement. Smooth mids. Doesn't quite achieve the 30.8hz of the fundamental of my B-String (F3 ≈ 50hz) Xmax 9.8mm / Xlim 17mm).