Quote:
Originally Posted by omendelovitz /img/forum/go_quote.gif
Back to soldering: uncleaned solder mask is highly common these days, I've seen that kind of quality on even high end electronic DACs, portable amps by manufacturers other than Larocco (I speak from experience). It's an unfortunate reality in electronic manufacture these days. The good news is that uncleaned solder mask should not affect SQ, and that poor solder joints are more likely a strength risk than a SQ risk. I'm not defending Larry's quality or tactics, just providing some basic FYIs to people's questions/concerns.
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Disagree on two points...
- That's not solder mask...it's flux...
- ...and it is not really an "unfortunate reality" in electronic manufacture. What it is, precisely, is unmistakable evidence that every component on the board was hand-soldered (using rosin core flux solder). If the board we're soldered by machine (via SMT reflow process:
Reflow soldering - Wikipedia, the free encyclopedia), there would be no evidence of flux post-process.
Now, hand-soldering isn't necessarily a bad thing...and it likely has little impact on SQ...I do agree on that point. However, cleaning flux is fast and simple with a little solvent...and ultimately presents a more professional end-product to the customer (I believe this topic has been debated to death on another very respected amp on this very forum).
Also, I feel that the hand-soldering work performed on this PCB is not very professional looking...
- Many (almost all) of the SMT resistors have too much solder (resulting in large blobs of solder)
- Some of the joints have unsightly solder tails.
- At least one of the resistors pictured does not sit flush on the PCB (but at least appears to be securely soldered)
- Many of the unused pads are covered with solder...possible evidence that components were previously installed there and then removed, or maybe solder was just accidentally applied in these locations
- The solder on Q1 has all four legs on one side of the component bridged together. I'm sure these legs are supposed to be electrically connected anyway (per design), but this should be done on the PCB and not via this huge solder blob...it's amatuerish.
Again, impact to SQ? Yeah, probably minimal-to-none. But for a $500+ pocket amp that, let's face it, probably has no more than $50 worth of parts under the hood, I would expect better. Much better.
The following statement appears on the Larocco website:
Every aspect of the Diablo is enfused with precision and performance.
When I look at the solder job on this PCB, the above statement almost reads like false advertising.
Peace,
Graz