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**Alan Wheeler** · 10-02-2006, 12:01

OK, lets get this into perspective. Unless you are a fool easily departed with money, you are nuts to consider spending tens of thousands of dollars for a system to go on a boat. I used to say this to guy's dribbling over a hundred grand pair of speakers. Yeah OK, so what sort of room are you putting them into. Cause it better be a damn good acousticaly designed environment.

So lets be real here. If you are looking at an entertainment system, then sorround sound is really cool. Plus, depending on the features of the amplfier, a surround sound system can also become a powerful tool. I recomend Denon and Onkyo equipment for most "home theatre" installs. They are both well made and sound good and solid. Onkyo have a cool feature.You can have surround sound for your theatre area, so you can have your 5.1 dolby speaker set up around the saloon area for DVD watching. Surround is cool for DVD as most DTS stuff comes alive with it. Surround "involves" the listener in the movie experiance. As for music, stereo is just fine, but some new material is now beign especially recorded in Dolby digital, that sounds plain boring in stereo.
Anyway's,I am getting side tracked here. The Onkyo amplifier has the ability to have a second remote speaker system control. You push a button, and have full control over a second speaker system somewhere else in the vessel. Maybe outside or what ever. I had my own 30 seat theatre in my home. Purpose built with full theatre surround. But I also had an otuside entertainment area for summer evenings. I could pipe the music out there when I wanted to, without having to have a whole seperate system.
I also had ceiling speakers in every room and a 100V audio line and volume controll in every room. So you could relax in a bath for instance and turn up some music.

Pete, the RMS figure is used because that is the actual heating value of a waveform. It is a way of stating the "real work done". Average is slightly less.

The real story behind speaker cables. This is one area that is so easy to get caught in. Some people will sell you so much crap in this area. OK, the most important aspect of good audio is a thing called Dampning factor..DF.. DF is the a factor of the output impedance of the amplifier. It is a very low figure and will be measured in a point of an ohm. It is derived in a way too complex for this forum, but it is expressed in a number. eg, it maybe DF=<100. Ok, the importance of DF is that it becomes the electrical break for the speaker cone. In basic terms, The RMS power of the amplifier is what say's to the speaker, OK go forward or back now and at this speed. But the DF is what acts as the break. When the waveform has reached it's peak, you want to control the cone and have it stop precisely and start traveling on the next part of the complex wave form. So DF is all about controll of the cone. Poor control equalls distortion. Distortion by the way, is anything produced that is not part of the original source. It is not just the clipping sound you hear when something is turned up to loud. Poly cones have their own "tone". That can be called distortion. ALL materials and speakers ahve their own "Tone". Ever hear of things called the "british" sound or "american" sound.IT's just a tone and thus distortion.
Oh, valve amplifiers arew highly regarded as "warm" sounding. Actually, a vavle ampl is loaded with Ahrmonic distortions that tend to "warm" a sound.
OK I am off on a tangent again.
Back to the DF.. well the biggest influence on DF is infact the resistance of the speaker cable. It doesn't matter what the cable is made from,it is all about getting as low a ressitance as possible.So the rule of thumb is, the heaviest cable praticle and the shortest run possible. And no, it doesn't matter abotu the cables having to be equal lengths to each speaker as some say you have to. Electricity travels at the speed of light and even 10's of yards difference in length equals nano seconds difference in arrival times.
The other aspect of cable is it'scapacitance. A simple audi filter is simply a capcitor and resister in circuit. A capacitance is a natural aspect of two wires side by side over a distance. You can't get away from that. But you can reduce the resistance, thus reducing the affect of the filter. The only other factor in speaker wire changing the "tone" is if you have toomuch and it is all coiled in a heap. It will produce an inductance.
Hope that was interesting and not boring. Feel free to ask questions if you want.
I none of you mind me blowing my horn here, but I am rather proud of what I did. Here is a project I designed and project managed. If you look at all the case studys, all of them I project managed and helped design.
http://www.audioautomation.co.nz/casestudys/jade.html

ssullivan · 10-02-2006, 13:54

Amazing... such a wealth of info. What other cruising site could you pop in a search about setting up a system in a boat and come up with this kind of stuff??

Great job, Wheels.

**Alan Wheeler** · 10-02-2006, 14:42

Oh and I had one other thought. Speaker impedance.
Car audio uses 4ohm impedance. HiFi uses 8ohm impedance. A 4ohm speaker will sound "louder" than an 8ohm speaker. It doesn't mean it IS louder, it is a function of complex stuff. But in the Car audio world, it is how you get the sound power from low power output devices.
Be vary careful about hooking up HiFi equipment to car speakers. Most home HiFi equipment is not designed to take loads as low as car audio speakers. It causes major stress and over heating of the output devices and can cause the amplifier to fail or go into a protection mode if it is designed with such.
It can be done and is easy to do. Basicaly, use two car speakers in series. This presents 8ohms to the amplifier. With two speakers you get more audible power. It's called "mutual coupling". Ummm, that's if the speakers are close together. Actually it's another reason why you see multiple drivers in the same pass band in a speaker box. They are like doubling the horsepower of the sound. It increases the bass response as well. There is no other reason, even though once again, many speaker makers wouldlike to tell you are inertia and all sorts of other crap. Once again, they have no clue. Ummm, let me translate. Passband is the frequency range a driver is being used to deliver. Driver? OK that is the term we technically give the little round thing that makes all the noise. It is more technically correct to call it an acoustic motor or a transducer, but driver is kinda an industry standard. A speaker is someone that speaks.

If anyone in the US is really into audio and wants to get hooked up with some way cool speakers. I mean by this, probably the most accousticaly accurate speakers you can ever get, then let me know and I will tell you a couple of guy's that build them. And they are not expensive either.

What makes a speaker box good??? Well, this is another area of BS. Every man and his dog has some new design of box, new design of driver blah blah blah. Well actually, drivers are not something just anyone builds. Actually many drivers are built by the same few companies.
So how can one speaker box maker claim to have a better box than another when sometimes the divers are the same thing.
The next thing is, there are some very strict rules of physics in designing the box it all goes into. You can't break the rules. so although one box may look different to another, diamensions inside are ruffly within the rules applied by the laws of physics. So what makes a box "good"?? it's all about Phase correctness. No not something from Star Trek. Phase correctness is complex. Waaaayyyy to complex for here. Infact, waaaay to complex for almost anywhere. But it is about sound information arriving to the listner in correct time. If the signals from differing sources, i.e. stereo are not in perfect arrival time, then the signal will cancel itself out, to a degree dependant on the phase error. So you don't "hear" some sounds that should be there. Now on an even more complex point, the same thing can happen from the one speaker box and from even one driver. I'll finish with this so as you can all have another breather. Sound is NOT created in the driver cone. The driver cone is an "impedance matching" device. The soumnd is produced down in the voice coil. The cone is what couples the Voice coil to the air. Different frequencies will travel up the VC and out onto the cone and will leave the cone at different points along it's surface. It's a result of the wavelength. So higher frequencies leave the cone close to it's centre. Lower frequencies leave the cone towards the outer area. This means you now have different frequncies leaving the cone surface at different times and arrive at the listener at different times. Multiple drivers where each drive does a different pass band, have to have a crossover in the circuit to ensure the driver gets only the frequency range it is designed for. But the Xover also produces distortion and time "smearing". So the real money goes, or should go in that Crossover design. You will also see on a lot of HiFi boxes, silly little centre cone thingies. They call them Phase plugs and are supposed to correct phase problems as I described above. So far, all I have seen are BS. Not one has been designed to do the real job. Why? because a real phase plug on a home speaker would make it look ludicrouse and no one would buy it.

10-02-2006, 18:01

I can not think of a single thing to add about amps. In fact, after reading Wheels' posts a couple of times, I am searching for someone to issue me a degree

As for the TV, LCD is the way to go. It is durable, and compact. It will operate fine from 12 volt, or AC, and the quality is very good. When we purchased our set a couple of years ago, Sharp had the best technology. We have the 22" Sharp Aquos, and have been very happy with it.
The only other thing I would add is leave room for the Karaoke machine

**Alan Wheeler** · 10-02-2006, 19:04

I agree with the LCD. Less power consumption than a CRT. Only problem with LCD, they allow a certain % of pixal faults before they will honour warranty. That may or may not be a problem for some. For "perfectionist" me, I expect it to be perfect. Especially with the money we have to fork out for them, (at least here). I am sitting here in front of my LCD monitor that has one green pixel lite up bright right in the middle of the screen. Dang that annoys me.

Don't take this the wrong way, but....Yeah Kai Nui, when it comes to audio, I used to play with the big boy's. Work was never boring. We worked at the frontier of design and physics. Put it this way, if I was part of a team that worked for NASA, we would be working on shooting for the Moon. Oh yes, there are guy's that are involved with exploring the universe and are way cleverer than I will ever dream to be. But I still got to play in a very fun field at a very high level. We pushed the boundaries of accoustics and I was involved in some radicle changes in the audio industry over the last 10years. Not just in NZ. Actually if you asked a local sound company in your area in the US, chances are they would say, "Yeah we know Wheels!". I have made a lot of very good freinds all around the world in the audio industry. It was a blast.
Sadly due to several reasons, I had to, or maybe just decided to give it up as a career, but I still have my feet in the puddle.

CaptainK · 10-02-2006, 21:04

Wheels.

I own a Onkyo quartz synsathised amplifier. Got a great smoking deal on it. It has a set up for surround sound. But I do not have surround sound setup right at this time.

I personally backup the Onkyo as a great amplifier. And the price is reasonable.

mudnut · 10-02-2006, 21:18

Well, If the replys above dont scare the hell out of you than nothing will.I love the input,but,**** ,Jerry dosent sound like hes going to the moon with his boat.Like I said I love the input here,and frankly,Im amazed at what you dudes actually know.It seems like a lot of the people on this forum have number crunching down to a tee,scarey ****, and Im not knocking it at all but ,****,the man just wants an entertainment system.Surely there is at least one out there that fits the bill.Boy its a long way from when we had to make our own entertainment!!!Please dont think Im being rude or rude,but I will hope that you see the sarcastic humor that is present in my reply.

CaptainK · 10-02-2006, 21:34

Hey mudnut.

I understand your sarcastic humorous remark.

I'm the same way as well.

Hey!!! At least that's one thing we naturally have in common?

10-02-2006, 21:56

Wheels, I took it the right way. I am quite impressed at the depth of your knowledge on this subject. I picked up allot from your posts here. I have had some experience with acoustics design, and I am familiar with the electronics involved with qua;ity sound systems, but nothing on the level you describe. As for whether this was too much info or not, some people take their sound and video systems VERY seriously, and the very fact that this thread was presented the way it was leads me to believe that this is the case here. It is amazing how inexpensive quality audio and video components have gotten. I remember when a good qualit 100 watt car audio system cost a small fortune. Now factory stereos are 250 watt surround sound etc etc etc.
Personally, I have found that my Bose Acoustic Wave radio works fine on the trimaran. I may not add any other stereo system aside from this The volume is not very high, but the sound quality is second to none.

**Alan Wheeler** · 10-02-2006, 22:25

Yeah Mudnut, cptK and Jerry, I guess if I were to sum up all I ahve said, it actually will equate to, "don't get baffeld with the BS that some snotty nosed sales rep will try and sell you on". Keep things simple. so if I may, I would like to put forward just one more post. It summerises in a concise way all the above...ummm... I hope
1: Make a budget and stick to it.
2: The system needs to be easy to operate
3: The system needs to be easy to store somewhere.
4: Seperate components are a good idea. If one fails, you replace one unit.
5: Don't buy rediculousely expensive cabling. Make sure speaker wires are of reasonable size, but don't go overboard either. They have to be easy to run. You can use a standard two core cable for speaker runs.
6: Speakers inside can be paper cone type.(unless you have a very wet boat, but then, speakers may not be your main issue) Speakers outside need to be plastic cones. Ensure the speaker grill material is plastic or non-corrosive.
7: ensure you have a correct load of speakers to amplifier impedance.
8:There are now many systems available that have small satillite speakers like the Bose systems. Quite frankly, Bose is very expensive for what it is. Manufacturers like Panasonic and such have some very well priced and good sounding gear that will suit most average blokes needs and they are cheap and sound really good.
HOWEVER, be ware of one trend I see lately. Many manufacturers are now making equipment that work soley or have features that can be operated only via a remote control. Make sure that what ever you get, can also be operated fully via the front panel. If the batteries are flat or you break or lose the remote, your system is a dead duck.
9:Unless you have a mega yacht with a really big living space, you are simply never going to appreciate the sound of a ten thousand dollar sound system.
10: An LCD TV can do more than JUST be a TV. It can also be a very good computer monitor. But few monitors make good TV's. So invest int he TV and use it for other things.

And one final point. Should the plain horrible ever happen and sea water ever gets into electronic equipment. DON'T PANIC. Also DON'T TURN IT ON.
Remove from the power and remove the top. Pour boiling water all through it and allow it to dry for a good day. You will find it will be right as rain. But if you ever turn it on with salt water in it, it will destroy itself.

10-02-2006, 23:20

One important aside to what Wheels just said. Not all the LCD TV's will work as monitors. I tried it with the Sharp, and it even states in the manual that it will not work. I bought an adapter to try to force it, but the resolution could not be adjusted beyond, I think 640x480. It was unusable. This is not the case with all of the LCD's so check the unit first before purchase if this is your intent.

ssullivan · 11-02-2006, 06:53

Quote:

Kai Nui once whispered in the wind:
I can not think of a single thing to add about amps. In fact, after reading Wheels' posts a couple of times, I am searching for someone to issue me a degree
As for the TV, LCD is the way to go. It is durable, and compact. It will operate fine from 12 volt, or AC, and the quality is very good. When we purchased our set a couple of years ago, Sharp had the best technology. We have the 22" Sharp Aquos, and have been very happy with it.
The only other thing I would add is leave room for the Karaoke machine

We have the same Sharp Aquos. I would 2nd Kai Nui's suggestion. The LCD picture is great and the unit has been very reliable.

I wish I would have known about the speakers Wheels talks about before I bought everything for our entertainment system. One of my most prized possessions I had to ditch were my NHT 1.5's. They were a hand matched pair (hooked up to an oscilliscope at the factory) that a friend won for selling the most NHT stuff. I really miss good quality audio. Unfortunately, I can't see spending thousands on anything electronic for the boat, since it will rot away in the salt environement anyway.

**Alan Wheeler** · 11-02-2006, 10:30

Ummmm, I think you are too harsh on your idea of things rotting away. You have a big boat, plenty of airflow and decent heating.
Salt is "not" in the air like many would suggest. It can't, otherwise we would have salt rain. Salt gets onto things by contact or by a leaky boat. Maybe a hatch being open in some ruff stuff. So a set of speakers should last inside a boat like yours just as well as in any home.
By the way, we run a Dehumidifier. What a majic invention that is. The boat is always dry feeling.

Jerry · 11-02-2006, 20:48

Thanks for all the info guys......I've made a decision to get new strings for my guitar......just kidding, i really am grateful if not a tad bit overwhelmed.