Amp design logic

04-23-12: River251
I was really hoping for a discussion of the components in a $1000 amp vs those in a $50,000 amp, and how much they, vs the designer's intellectual property, contribute to the quality (and cost) difference. In other words, can I take a standard amp design, use the best available parts, and get the sound of the $50K amp. If I can't even get close, the sound quality must come from the circuit design.

"Best" in this context would have to refer to using the same kinds of parts, but in versions that have tighter tolerances and/or more idealized behavior. My expectation is that Doug's answer is correct -- you can't make a VW into a Veyron by using upgraded versions of the same kinds of parts. You have to use different kinds of parts, that are not direct substitutes. That in turn will necessitate differences in circuit design, mechanical design, thermal management, and overall architecture.

Also, I would point out that "better" parts, however that may be defined, will not necessarily perform better if arbitrarily substituted into a given design, and may in fact perform worse, depending on how they interact with the surrounding circuit. For example, substituting a faster transistor or integrated circuit for a slower one can result in all kinds of problems, depending on the function the device performs. In digital circuitry that would include electrical noise problems such as signal crosstalk and "ground bounce," and increased sensitivity to impedance mismatches. In analog circuitry it would include possible increases in rfi susceptibility, intermodulation distortion, frequency response peaking, ultrasonic ringing, or even potentially damaging oscillations.

And I agree with everything in Bryon's characteristically well thought out post.

Regards,
-- Al

Sometimes, (not all)you actually get what you pay for. In terms of amplifiers, tube or solid state, it depends on;
1) time and salaries associated with design, test, manufacturer, R&D (this is huge), marketing, sales, repairs, etc. These all have to factored.
2) parts. if you require new parts or chasis designed and built that are not off the shelf, then you will pay a lot more money. Also, if you require a small amount of parts instead of a lot of parts made, then the manufacturers will charge more.
3) Transformers, yes this is parts, but transformers are the major factor in parts costs. These are not cheap and are made to your specs by transformer manufacturers in small quantities. hence high prices.
4) This isn't the car industry. If you are a small company, you have salaries and a price points you are designing to. You also have limited manufacturering capability.
5) repairs, service and admin support.
6) are the parts matched, and tested and the ones that didn't fall within the design criteria rejected? Well, these didn't come free. If you really are a stickler for matching parts and having parts within a certain criteria, well you have to buy hundreds or thousands of parts just to find a few that fall within the specs. you paid for those rejected parts and have to recover the cost.
7) design, manufacture timeline for a given product before new and better comes out. Say, three years. you have to recover all of your costs for the above, plus profit, misc. expenses, legal costs, human resources, (this is a business remember) and the costs for R&D for the new upgraded amp.

Several classes are taught regarding this type of thing. This is not straightforward and easy. It definitely isn't just the cost of simple parts. Go out and try to make an amp in the $5000.00 or $50,000 price range (sales price) and see what it takes.

Call Motorola, or tube manufacturers, for proprietary parts, small quantity and see how much they will charge you. Simple cheap sheet metal casings, aren't happening on quality amps. You need heavy metal, to help eliminate unwanted vibration. This does cost. Transformers? hah! this is stupidly expensive. Threshold like heat sinks for your class A ss amp? Get ready for sticker shock. matched devices? well get ready to buy thousands just to find a few that match. How much time did you take to design, construct and test? and how many people were part of this effort? You have to pay them and they aren't cheap. training, traveling, Human Resources, etc. Wow! And! one stupid review from some person that is full of himself/herself and you just lost a ton.

Also, where did you get the circuit design from? Osmosis? you had to go to school, and take years of R&D. Same for circuit board layout design, chassis design and construction, wire your own transformers? good luck. Make your own capacitors, have fun. Can't find the parts quality you need off the rack? Well then you have to do it yourself or pay someone to do it. these all mean up front the costs and you have to recover it from this amp sale. How many did you plan on manufacturering and selling? Take the total costs to design, construct, sell, HR, all of the above, including salaries, and factor that into the total number you plan on making. This determines your price.

So, yes, sometimes you actually do get what you pay for.

This is why many fail in this business. And also why many don't submit their products to magazines for reviews. Not that they don't make quality equipment, but because like wine, all you need is one stupid review, one reviewer that had a bad day and you are out of business.

enjow

You can't turn a Volkswagon into Bugatti, but you can alter/modify cars to excel at specific purposes. I think it is obvious that cars used in many races are based upon street models but have many parts changed/exchanged to upgrade performance.
Their is a thriving industry in this hobby living off the same idea. I can hardly think of any component that hasn't been or can't be modified. I myself can do little beyond rolling tubes, but I do that with some zeal, and I have employed others to mod a few pieces.
Some people do claim that modified components make their gear the equivalent of something much more costly. In any event it is abundantly clear that their is a strong belief in the value of modification.

River251, perhaps you might want to consider cutting your teeth on projects like these:
http://www.diyaudio.com/forums/pass-labs/

River251, With all due respect, based upon another recent thread you started, I think, at least for the present time, you might be in way over your head. Just think of the appropriate test equipment you'll need. It's not as simple as plug and play. You might want to begin with a simple starters kit, before attempting to supplant $50K amplifiers, regardless of their markup.