Ben quand on connait un peu le contexte au niveau des forums internet, des différents débats tordus en matière d'amplification, et parfois les fabriquants qui se tirent dans les pattes en critiquant ouvertement les produits des uns et des autres, on se dit que c'est moins une blague que ça en a l'air.
C'est quand même bien un peu une réponse voire une attaque envers les personnes qui mettent en avant parfois avec des arguments fallacieux le PTP ou les lampes qui doivent êtres fixées sur le chassis. "Moi je fais ça depuis 89, je fais du haut de gamme avec des PCB et des lampes fixées sur le PCB, qui plus est j'en suis fier; les gurus internet (sous entendu tous ceux qui n'ont pas fait leur preuve comme moi en montant leur boite et qui donnent des conseils à deux balles sur le net) baisez tous mon cul".
Je veux bien croire que c'est une blague mais je perçois pas trop le comique de la chose. La prochaine fois au lieu de se lacher sur ses PCB, il n'aura cas le faire sur son site internet. Ce sera un peu plus direct et ça évitera un lag de deux ans.
Oui ça me gêne pas plus que ça qu'il fanfaronne, il est effectivement fondé à le faire, et oui au niveau de l'art et de la manière c'est clairement plus Californien que "British" lol.
Citation:
12) What are the advantages of printed circuit technology over point to point wiring?
For the record, all VHT amplifiers are primarily hand built PCB assemblies. No automated board stuffing or flow solder processes are used. Honestly, if we felt that the sound quality or execution of our products would be improved by the exclusive use of point to point assembly, we'd be doing it. On the other hand, hard wired assemblies are utilized wherever it is determined that sound quality, reliability and consumer safety is best achieved. AC mains, main power supply, board to board interface, long, high impedance audio signals and rectifier tube sockets are areas where hand wiring is clearly the superior method. All other components such as resistors, capacitors, pots, switches, tube sockets (that's right…Tube sockets…pre and power) and various other items are properly and confidently PCB mounted. We use top quality double-sided glass epoxy boards with heavy copper plating and plated through holes for maximum reliability and signal integrity. Boards are mounted on heavy-duty tubular aluminum supports attached to the chassis with machine screws. You won't find any floating preamp boards or pop rivets here. Small tube sockets have large diameter solder pads and a center support pin, also soldered to a large plated through pad. Large tube sockets are attached to the board with heavy tubular aluminum supports and chassis mounted with machine screws to form a solid and bulletproof board to chassis assembly. We know of no other amplifier manufacturer that uses this rugged and costly method of construction. In fact, most other PCB mounted preamp tube sockets we've seen don't even have a center support pin!
There are a lot of misconceptions and misinformation surrounding the debate over printed circuit board versus point to point assembly. The problem we see is that many times information gets taken out of context, leading to the creation of fresh manure. We will discuss the issues as they relate specifically to the manufacture of our products. Sure, we're probably going to hit a nerve or two somewhere along the way, "but" as Stuart Smalley reminds us, "that's…sigh, OK".
Since we're all pretty much in agreement about the origin of point to point wiring and PCB's, we'll skip the history lesson and get right to the pros and cons.
We encourage your questions and comments.
A) Sound Quality
Contrary to what you may have heard, great tone is not the exclusive domain of point to point wired amps. Even the use of top quality components and meticulous assembly methods do not guarantee good tone. There are plenty of examples of great and lousy sounding products in both point to point and PCB categories.
There are well built, mediocre sounding amps and sloppily thrown together, great sounding amps. In fact, undesirable sonic characteristics frequently attributed to circuit boards are much more likely to occur in point to point wired amps. Stray capacitance, phase cancellation, signal degradation, and crosstalk between stages are common problems in point to point designs. Most of these conditions are easily minimized or eliminated in a well executed PCB design. One interesting and often overlooked side benefit of PCB design is the ability to precisely control the way the board will "sound" by experimenting with placement of sensitive components. We frequently use this technique of "tuning the board" to tweak various parameters of a circuit which might normally be accomplished with the relatively "brute force" use of added capacitance or tone robbing bundled wire harnesses.
B) Consistency
One of the most attractive benefits of PCB construction is the inherent consistency of the process. Once the design is complete, it can be easily reproduced with a very high degree of accuracy. In our particular case, the object is to produce an amplifier that meets a set of pre-defined sonic and functional criteria. These criteria are built into the board design and are not subject to the wide variations in tolerances normally found in the point to point assembly process. In the late fifties, state of the art point to point construction ( i.e. military and recording/broadcast electronics) incorporated "turret boards" that supported most of the small components on Nickel/Silver plated posts staked into thick Fiber or Glass/Epoxy strips. The bulky components (pots, jacks, switches, filter caps, meters and transformers) were chassis mounted and meticulously hand wired to these boards. Some of today’s more popular (and more expensive) point to point amps utilize low cost phenolic "terminal strips" with thin Tin plated lugs instead of the much more rugged turret boards (and while we’re at it…get real with those filter caps bundled together with electrical tape!!!). The terminal strip method usually requires much more extensive use of wire, solder and wiring harnesses, resulting in a circuit layout that is subject to wide variations in circuit behavior. Two identical amplifiers built this way are very likely to, and often do sound completely different!
C) Reliability and Serviceability
Needless to say, there is a right way and a wrong way to do everything. We could be a little bit more generous and say that there are an infinite number of interpretations of the term "cost effective". I have to admit that there are legitimate reasons for peoples seemingly genetic aversion to printed circuit boards. Every time I look into the guts of a PCB amp that falls into the "cheaper to replace than repair" category, I think "here’s another one I’m going to have to defend myself against". It’s a fact however, that circuit boards dominate the electronics industry. Therefore it is important to remember that for every department store consumer electronics product that’s on sale this week, there’s an Internet connection bouncing off of a satellite orbiting our fair planet that will probably operate flawlessly far into the next century…utilizing printed circuit boards.
How do we account for this large technology gap? Simply stated, printed circuit boards pretty much do exactly what the designer intended for them to do. Nothing more, nothing less. If top notch performance and long term reliability are the design objectives, then the end product will perform and last provided that it is correctly engineered. In this context then, it is logical to conclude that a well designed, high quality PCB based amplifier is more than likely to perform as well or better and last easily as long or longer than a point to point wired amp.
D) Cost
All things considered, we feel that the point to point method of amplifier construction is unnecessarily time consuming and excessively costly. When you pay a premium price for a quality point to point amplifier, it is pretty much understood and taken for granted that you’re not necessarily paying for performance and flexibility. A fat price tag on a boutique amplifier frequently indicates nothing more than what the builder thinks the market will bear. On the other hand, if you understand that you are literally paying homage to the idea of Old World Craftsmanship and appreciate the time and effort that goes into a nicely made piece of modern nostalgia, then you are probably making a justifiable purchase. A well designed, PCB based amplifier sacrifices nothing to sound quality, construction quality or long term reliability and value merely as an automatic consequence of the use of printed circuit boards. The labor saving aspect of PCB amplifier construction makes it possible to offer a wide variety of features and functions which translate to a higher "Bang for the Buck" ratio. It is important to understand this important distinction before plunking down your hard earned plastic.
