Point-to-Point wiring vs. PC Board . . .


I've recently bought a "boutique" quitar amp (a Carr Hammerhead), which features point-to-point wiring and other very high-end components. The improvement over my 4-year-old Marshall with a pc board is staggering!

Can I expect the same from stereo gear? If so, what are the names I should look for?
crazy4blues
Sean makes some very good points. I'd also like to add the following from the perspective of an electronics designer:

1. For power delivery, point-to-point wiring can generally carry more current with less voltage drop than a cheaply designed PCB. If a PCB makes use of wide, thick planes for power distribution, it can compete with point-to-point wiring up to the several 10s of amps range. Of course this adds to the cost of the PCB.
2. For low-level signals, a PCB is always preferable. Such signals don't carry much current and benefit from close mounting on a PCB. Surface mount circuits can also be made to be much higher performance than through-hole circuits due to the shorter trace lengths that are possible and, in the case of high-speed signals, the lower pin inductance of the parts. Stripline construction can be used to sandwich the sensitive signals between ground planes which further reduces noise pickup. As Sean said, the quality of the layout is critical. You can have the best circuit design in the world and a poor layout can ruin its performance. A good layout will produce repeatable results for each unit made.
3. PCBs can have much higher reliablility than point-to-point wiring. PTP wiring involves hand soldering, with results dependent on the soldering skills of the assembler. Automated PCB assembly techniques remove that variable from the equation.
4. Repair is generally easier with PCBs.
5. If labor is cheap, PTP can be a cheap construction method, otherwise PCBs are generally cheaper.

PTP wiring has its place, in the wiring of power supplies and the output stages of power amplifiers, but most other applications will be better served by using PCBs.

I have noticed that a lot of audio companies are behind the times when it comes to PCB layout techniques. Most are designed for minimum cost, rather than high performance. 2-layer boards without planes are common. My work involves high-speed digital design as well as high-resolution data acquisition systems and I rarely use less than 8 layers for a design (4 trace/4 plane). Simply incorporating a ground plane improves noise performance markedly.

So, back to your original question - the improved performance of your new amp is most likely due to the circuit design using premium components rather than the use of PTP wiring. Instead of looking for companies that use PTP wiring, I suggest you look for the ones that use multilayer PCB designs (with planes) and high quality passive components such as polypropylene or polystyrene caps and metal film resistors. This will give you a better indication of the skill level of the designer. Rowland and Meridian are good examples.
C4B's: I can't say that i've seen every piece of gear on the market, but i can say that out of those that i've seen, every single one of them can be improved upon with relative ease. Cost cutting in parts, poor design lay-out, redundant circuitry, etc... are all to be expected when i "lift the hood". Some products are simply designed and implimented in a more uniform manner than others, but even the better ones show their short-comings.

As far as what you like and what you expect out of a piece of gear and / or system, i have no idea. Personally, i prefer shorter signal paths and point to point wiring will give you that BUT you can also run into other problems using that approach. As such, it is not so much the design or how that design is implimented, but the end result that counts. Both design and implimentation are VERY important, but i've seen lesser designs that worked quite well because they were implimented in a manner that was less detrimental than other gear that was better designed, but laid out like garbage. Sean
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Hey, Sean, thanks. I totally agree with you re Marshall, and, believe me, the same can be said for Fender--probably even more so.

So what has been your experience with stereo gear? Any preferences? I have Rogue and VTL gear (pc board stuff), and I'm wondering if I can achieve the markedly better results in audio gear that I have with my guitar amp.

Thanks
It also depends on the model of the Marshall amp. There are a few models that have the Marshall sound that everyone knows and other models are more afordable.

Happy Jammin'
Point to point wiring typically results in measurable variations from unit to unit due to variances in impedances. Obviously, not all the wires will be routed exactly the same, nor will they retain the exact placement and shapes that they are configured into when first built. Circuit boards have their advantages when properly built and designed, especially if one is looking for consistent repeatability on a mass production basis.

As far as a limited production guitar head "beating up on" a mass produced head, what did you expect? This is like comparing a Sony / Pioneer / Kenwood, etc... component to a "boutique" component. Once a manufacturer establishes themselves, like Marshall has, they become more concerned with maintaining that reputation while keeping production costs down / profit margins up. They have no need to refine their products / cater to a smaller market since they've already got a major portion of a far larger market due to commercial success.

Having said that, it is not uncommon for folks to take their mass produced units and have them "hot rodded" to better suit their playing styles and the sound that they desire. Personally, i don't think that Marshall has made anything that can stand up to a Peavey 5150 or Ultra 120, let alone an even smaller, more detail oriented manufacturer. Sean
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