Hermida Audio - Dover Drive

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Re: Hermida Audio - Dover Drive

Postby sanfi4u » 06 Apr 2016, 22:55

deltafred wrote:
sanfi4u wrote:Because real life components are not ideal. They have their imperfections (non-linearity, noise, losses) that affect the sound quality. Going smaller usually makes the situation even worse. In particular in electrolytics department. Nothing new actually.

If you are going to make statements like that you need to back them up with references to relevant data to support your argument.

Having your own opinion is fine but that doesn't make it an undisputable fact.

Hmm, tons of statements of various sort and kind across the fora and no proof requested. What makes mine so special?
OK, let's have a closer look at what has been stated. Actually most of the statement is straight forward. Here's a little drill down:
- all real components (including passive ones) are not perfect and have noise, losses, non-linearity. Just look into the specs. It's all there. THD is missed in some specs. But you'll find many test results across the Net. See tantal caps and electrolytics in particular.
- Situation got worse with smaller parts? It's in the specs as well. Take any electrolytic cap spec. Mind caps got bigger when max voltage grows. See what happens there.
- Imperfections affect the sound? Is there any other option if device is made from these parts? Noise floor gets higher, THD grows. No other way.
- Are these changes in the sound substantial enough to be heard? Or in other words is human hearing sensitive enough to really care about these changes? Or do these changes make any sense in the real life situations?

Well, the last bullet is a hard one. There's no just one right answer 'cause perception of the sound is very subjective. I'm not in a position to start one more endless discussion on the topic. You'll find many of them across the net. Let's assume we are all different, we have different critical listening experience and use different rig. If a person don't hear the changes it's the same as if they do not exist at all. It's a very beneficial situation. He can pick up any pedal he likes regardless of the technology that's been used. Good for him.
If a person can hear the difference huge pedal market lets him to find the pedal and technology he likes (mind Dover Drive Old School edition). Seems like we have a win-win situation these days, aren't we? [smilie=rlp_smilie_242.gif]
P.S. Just ended up one more Dover Drive Standard vs Old School test. Old School edition sounds really nice. Definitely the keeper! :D
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Re: Hermida Audio - Dover Drive

Postby MoonWatcher » 10 Apr 2016, 23:08

sanfi4u wrote:There's no just one right answer 'cause perception of the sound is very subjective.

Well, that said, some effects only have been produced as SMT-based, like Tech 21 pedals. I think some sound quite good, even if we want to assume that component quality was consciously skimped on. I built a vero-type version of the Tech 21 XXL, and since it was non-SMT, I suppose some of my components might be considered "premium." That said, it sounded identical to the real Tech 21 pedal when A/B'ed.

There are also lots of effects that use only the most generic grade components, SMT or otherwise. I think it's quite rare that something like a "premium" electrolytic or tantal cap is chosen for audio characteristics. Most of the time, they seem to be bought in bulk, based on lowest price. But what I think is more important to highlight is the number of vastly popular pedals that use general purpose capacitors/resistors/etc. for the whole thing, and there are countless examples that sound quite good. I've witnessed some DIY builds of the same thing using "premium" parts, and couldn't detect a significant improvement in sound. In the case of something like an old ProCo Rat vs. a new one (with identical component values, just so we are comparing apples to apples), there are some new ones that feature metal film resistors, box caps, and so on (a friend of mine got a white face reissue Rat a few years ago that I got to check out). When compared to a decent Rat from years ago, with regular carbon film resistors and the cheap mylar "greenie" caps, I honestly can't hear a difference.

In the case of something like the Dover Drive, it is important to remember that it's purposefully designed to distort. I simply do not know of audio components that are designed to make clipping sound better. If anything, they are optimized for the opposite. Since we are purposefully causing distortion, it seems to me that pedal designers are on their own - it's really more a matter of tailoring the clipping (hard/soft/contains crossover distortion/etc.), and then filtering it to not sound unpleasing to the ears. It's basically reverse-engineering, so determining what is "premium" for these applications really comes full circle to your statement about "perception of sound is very subjective." It could be argued that perception as to how to create such sounds is equally as subjective, and it's impossible to qualify that component A is possibly premium while component B is inferior.

I also have at least one amplifier that is a mix of SMT and through-hole construction. In one of those amps, the op amps that are non-SMT seem to have been deliberately chosen for specific characteristics, and the amp doesn't seem to suffer sonically from the SMT-based sub-circuits. While I understand that it would require building a 1:1 replica with all non-SMT to verify this, it's simply not practical.

Many subtleties also go out the window when much of this gear is used on stage in a band context, even if you can clearly hear a difference when A/B'ing in your living room. Well, at least that's been my experiences.
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Re: Hermida Audio - Dover Drive

Postby Kennc_dk » 30 Jun 2017, 22:53

just added the traced schematic to the forum as a 'traced' post: viewtopic.php?f=7&t=28453
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