Archive for June, 2008

Unsolicited Free Audio Advice

June 11, 2008

Attributions For Above Picture

Looking for advice on your next system? No? Too bad. Here it is.

Modern codecs (A/D & D/A converters) are 24 bit 192 kHz and a dime a dozen. You can’t get much better than that as far as noise and dynamic range are concerned. So the most effective place you can spend your money is in an easy to use receiver, the Speakers, and amplifiers. I say easy to use because many receivers are designed by UI buffoons. They are the intersection point of a system and ease of use and setup are at the top of my list.

Tube amplifiers have distortion that is more natural to the human ear. Class A amps are low-power and inefficient, but have the lowest distortion (most linear) if designed correctly. Don’t waste money on over-priced amps marketed with pseudoscience. The little distortion present in most modern amplifers isn’t really enough to fret over. If you think you can hear the difference, there are lots of folks like this guy offering $10K if you can in a blind test. Avoid the snake-oil vendors.

Now for some honest money saving advice and maybe a little toe stepping.

Bose is an interesting manufacturer. They have a well documented history of spending most of their money on marketing and almost none on research. Perfectly legal but I’d rather spend money on quality than marketing. Case in point: the Bose wave radio which is based on research from the 1920’s. It has one narrow resonance band at low frequencies that gives it its “full” sound. I have very little respect for Bose. They have some good stuff here and there, but it all carries the heavy Bose marketing tax.

Don’t waste your money on $700 power cords or expensive power conditioners/surge suppressors. They are pseudoscience BS but perfectly legal, like most of the herb and supplement market, and magnetic bracelets, etc. Nothing is gonna make it through the transformers, buck/boost converters, regulators, and capacitors that you are going to hear. Buy a $20 surge suppressor.

Also on $200 cables. If your system sounds better with one of these cables its probably because it is masking a ground loop that shouldn’t be there in the first place. Eliminate the ground loop first. You shouldn’t have to spend more money on 0-20kHz than the RF engineers spend on 1-2 GHz cable and connectors. This is a blatant ripoff also. Moving any signal in the audio range just doesn’t take that much effort to avoid noise and signal loss. Its actually laughable they get away with it. I could hook up your receiver with a coathanger and you couldn’t hear the difference. Speaker cables are the exact same. Oxygen free is BSt also. Buy something durable that is easy to tidy up.

As far as speakers in the home goes, there are great “practical” speakers that mount in the wall and use the space behind it as an enclosure. These usually sound great and because they use of the wall as a large “invisible” baffle. Speakers are the place you should spend your money. Sound for a home theater is considered “near field” and its actually 10 times easier to accomplish great sound here than filling a large space like a gymnasium or auditorium, where you need high-power drivers with specially designed horns for directivity. There is no need to spend thousands on a set of home speakers. I typically look at the specs (like Xover points, flat frequency response, and decent crossover design) and take a listen to make my decision. JBL’s are well designed, but you pay for that and then some.

I have heard some great chinese knockoffs from distributers like MCM. Here they are so cheap you can buy before you try. If you don’t like them, put them in the garage system. Get a good powered sub and you are set.

The things that can make or break a sound system are ground loops (buzz) caused by incorrect grounding, poor gain structure (distortion and hiss are present), crappy speakers, and an EQ that is incorrect. A good parametric EQ set using a dual channel spectrum analyzer is ideal, but not totally necessary if you choose the right speakers. You can’t set an EQ by listening to it. You can turn up/down the sizzle or the bass to your liking after the system is “flattened” however. Many people put in a “theater curve” by putting in a -3dB/octave dropoff after 2kHz after “flattening”.

I’ve stepped on a few toes, maybe even made an error or two. If you’re angry or dissatisfied with this post I am offering you a full refund. Otherwise feel free to respond with corrections.