/diy/ - Do It Yourself

>>468543
Well truth be told haven't seen any tube amp threads on here. But then again I don't spend a lot of time lurking.

Usually street price of an FP14000 is about 6500-7k. But I am sure you can find them cheaper.

As for the 60% I thought you were talking about changes in the speaker itself. Not the psychological differences. On that point yes I will totally agree. Most of what I see coming out of the cognitive neuroscience and psych fields about sense perception shows more and more that it is easily manipulated and highly variable and almost impossible to find any real baseline for.

Hmmm, interesting. I have never had BB delaminate on me. I will admit when I am wrong and if you're having/had issues with BB I will check it out. What was the source material when it came apart??

The point of my "amp specs who cares" line, is this: I don't trust any amp maker to give me even close to accurate specs. Lab gruppen seem to be pretty good all things considered but most everyone else is just trying to find new ways of making their products look good through inflated numbers. At some point I just gave up. I know who to go to for amps but never trust their numbers. I also have yet to see a double blind study finally put to rest the debate on amp sound differences. I don't have the time to get dozens of people to sit in a room swapping amps out and all that crap. Tried it before but someone always bitches about something. I just gave up and at this point just let the internet debate it. So yes the point stands, who cares what the amp specs are, they are meaningless and probably completely unrealistic. If it works and doesn't blow his speakers up it really doesn't make a difference.

>>468503

If you are pushing pressure to delaminate baltic birch (not cheap shitty home depot ply but actual baltic birch) you are dealing with massive SPL's which are not conducive to much more than number masterbation.

For sub amps we use these: http://labgruppen.com/products/fp_plus_series/c/fp_14000/ Some of the best sub amps on the market and flat to very low frequency.

Who really cares what the amp specs are. If you want to go down the path of differences amps make. Unless we are talking above 20k and below 40hz you are barking up the wrong tree. Most of us don't think amps really make a meaningful difference outside of incredibly high end systems with resolution to match OR very very odd speaker designs that have very goofy ass electrical properties orrrrrr old ass tube amps. Again not stuff I would ever see on /diy/ so why bother asking about it?

As for joining methods. wood glue and clamps are fine. That's about all you really need. Sure you can use dovetail joints or beveled cuts for joints or any other fine furniture joinery, but that is just for looks and for his build wouldn't change anything. So why bother adding clutter for OP to figure out?? And tools. Well for absolute basics a tape measure and a jig saw. Want to get fancier well a recip saw with a guide, or a nice table saw, plunge router, all the clamps you can afford, straight edge. Seriously that's really all you would need. OP didn't ask for joinery tips or what tools to use. So why make assumptions about that stuff?

Given the questions you are asking I would say you know dick all about the subject matter at hand. But that would be an assumption of you which I can't make because who knows what you know. Ask away though because I can do this all day.

>>468254

That's why hvac is so important in these spaces. And yes you can create ducting that prevents sound from entering and leaving your space. So called dead vents would be what you want to google. (It's easy to diy too. If you want more info on it let me know)

Ex.
http://acousticsciences.com/hvac-systems
http://www.soundproofingcompany.com/soundproofing101/the-dead-vent/

>>468440

This. And I agree with adding a brace on the back to keep the crack under compression.

>>468473
Oh and this post is just wrong...

First a driver doesn't have a perfect box. It has a preferred operating environment. That can change with not just enclosure dimensions but also shape, and layout/design. Sometimes horn, sometimes sealed whatever. But it's not a perfect box that will fit that driver but a variety of situations/settings that a driver will prefer. It can perform optimally and incredibly similarly (to the point that there are functionally no differences) in various optimized conditions such that it is in a preferred enclosure design but one that is highly variable. There is no single perfect box for a driver. That's a very old way of seeing things and just doesn't fit with current research.

Second. who uses punchier, or warmer or muddier? No one who knows what they are talking about. There are frequency and time domain parameters that determine those sounds and that is it. Box size does NOT determine that at all. You can manipulate those frq and td params in many different ways based upon enclosure size and design. If you think that is the case then you really need to listen to some of the builds that some guys on the HT forums have been doing with high VD large excursion drivers in smaller enclosures fed with amp power that is flat to near DC. Because when done right they are getting flat to 10hz in some cases. That my friend is the opposite of "punchy"...

Also where did you get this 60% from? Because there isn't a research paper in the AES database that will have that number. I think what you are thinking of is physiological and psychological changes in the listener as a speaker as a whole does not really change that much over time. Also to say that the average person can never build better is a fallacy. Lots of average guys have produced fantastic builds that any manufacturer would be proud of both in looks and sound qualities.

You can disagree with me all you want but the body of knowledge and facts back me up.

>>468450
>>468473

Yes similar drivers, and yes math the same. The difference is the environment and the desired signal output goals. Good sounding audio in a car is notoriously challenging, I have talked to some of the guys who engineer setups for marque car brands. They drink more coffee then grad students. Second point is in SPL comp world they just car about getting a big spl number. That can happen at 50% THD or higher. And happen in a 30 cubic foot or smaller rigid space at 50hz and up. That's not terrifically challenging. I can build a setup that will do lower than 5hz at 140dB with less than 5% THD in a 10-20,000 cubic foot space and have it run all day every day without fear of drivers melting coils or cones being ripped apart.

As for which company I work for, well I own my own company. It is a research firm and I do hifi stuff as fun pseudo hobby. Most of my acoustic work is actually in consultations for architects, studio designers, and sound scape design. Speakers and home audio though fun and fascinating takes up not a huge amount of my time. Also I am not a traditional manufacturer either, I do speaker comissions not build lots of pieces to place on the market. I only build when someone asks. And lots of the installation work is done by a couple guys who work for me. I have a couple employees but we are a small outfit that focuses on research and design not so much building. Though we like to do that as well. And to say pro builders shouldn't be on 4chan. Well who gives a fuck. Most of the audio guys are kinda crazy in general. I mean what's worse a brony or an audiophile? I lots of people who go on 4chan who are professionals in various fields. Don't be so suburban.

Oh and laminated materials are fine and in fact their construction can be far FAR more robust than any uniform material. But really I don't feel the need to argue the point. People smarter than you use these materials. And when done properly they are more robust. Full Stop.

>>467181

If you're getting air leaks you will be lowering your output potentially as they will each be acting like a tiny untuned port and could be messing up your higher order frequency range possibly causing a midrange cut and some additional brightness.

Padding the tweet may help. You may be also getting diffraction artifacts as things aren't flush mounted and non rounded edges. Diffraction noise can be the reason for some added brightness and harshness. Also you may be seeing some directivity drop off from the mid to the tweet. That tweet has pretty good looking directivity compared to your mid so that's another potential source of brightness. Also make sure to give that bigger driver a chance to break-in (yes there is lots of debate amongst experts but I have measured changes in pre and post break-in so I choose to think that can be a good thing to do). Also a cold driver isn't a very compliant driver so as bits of it "warm up" (both actual temperature and just the mechanical compliance changes that happen under use) you may notice additional "warmness" to the tone. And really don't discount your room either.

Perhaps try taking them outside for some listening to see how much of a difference that makes. Free air space may point out a design point to work with.

Not entirely sure what you have for measurement gear but that is never a bad thing to have because right now all the advice I can give is just speculation. I have no numbers to look at to really tell you what is happening, why it's happening or what to fix. I can just make educated guesses, but guesses none the less.

Hopefully it's just something minor and the brightness isn't a big deal.

>>466829

step 1: sacrifice goat
step 2: kill virgin
step 3: who gives a fuck you've achieved your final form time to kill your parents and anyone else standing in your way!

EXCELSIOR!

>>467915

Well rolls of neoprene rubber will be the easiet bits to use. Not sure why you don't want peel and stick? Do you want it to be removable.

I hope you realize that if it's removable you will likely have gaps or holes in the gasket resulting in air leaks - i.e. pressure leaks - i.e. places for sound to leak through.

>>467920

Though there are some good pieces of advice on /diy/ when it comes to speaker designs check out diyaudio forum, avsforum, home theater shack and the parts express forum. There you can see all the various kits that people have been using and discussing and get solid advice and dozens of links to check out. I won't do the leg work for you but those are the best places to take your initial first steps and go from there.

>>467245

Great you can produce 170dB sound pressures in a 30 cubic foot space at 80hz at 30%THD. Go fuck a rake.

Try making 5Hz, 150dB in 10,000 Cubic feet at .7% THD with the shit gear you have. Oh and have that setup be able to be maintenance free and without replacing burnt coils, ripped cones and fried amps every other day. Cause my setups will run at this limit 24/7 till you run out of electricity. Once you can pull that trick out of idiot mind then I will listen to your uneducated moron ass. There is a reason people in my line of work are paid a fortune for our expertise and why no one listens to you goofs with your fart cans. But hey, thanks for playing.

>>465560
Constant Directivity is a a big deal, fan of that part of his work

>>465654
Magico makes lovely and beautiful pieces! I have built a few stacked baltic birch enclosures inspired by their designs. I just couldn't help myself, they look too sexy!

>>465829
It was more thought experiment than anything. I call that a meh. And he has done lots of experimentation in the CD field that has been backed up by tom danley so I will go with him being both a good engineer and scientist. Just one who should stay away from psychoacoustic stuff. The guys leading the charge in PAL though seem to be sean olive and Dr. Toole. I always enjoy my visits with them and when they let me play in their lab.

>>465516

Bass setups that I am building for clients that go sub 15hz are where I am seeing this. More and more folks are wanting reference quality bass that can hit to 5hz with authority as there is the information in the tracks there so why not reproduce it. These are indeed big setups though with pressure waves that can approach those seen with some car setups ***we don't go stupid and make sure to stay within safe limits for hearing preservation*** Yes this is something you see in car audio on big number setups, but that's a totally different topic of discussion. lol

Oh and pic relevent, Baltic birch done right!

magico minis are brilliant speakers. admittedly insanely expensive, but such is the cost to play ball.

>>465473
True enough on the first point.

Second point though, I don't know the TS params (and too lazy to look them up) also not sure what the power compression range or excursion range for the tweet is. So an ~2500hz xo may work though you can see the mid is breaking up starting at about 3Khz, only a 1/4 octave above xo. 4th order wouldn't be steep enough to get that out of audible range. So a 2Khz would be better, but now you gotta worry about over excursion or power comp on the tweet. Course I don't know what the measurement of the cone break up looks like or how it sounds on that mid. But looking at off axis response break up is pretty rough, 5dB spike over half octave @ 60 degrees but a 5dB drop over that same half octave at 30degrees, looks like a rough oscillation in the cone there. BUUUUUUT that being said these are cheap drivers that look to measure pretty damn well all things considered. So I wouldn't see any issues with a 2k-2.5k xo. Just play around and see, wouldn't do anything less than a 2nd order though. Giving a thumbs up thus far for drivers.

Pic unrelated again but god i love that tweet!

acoustic researcher, engineer, consultant for architectural projects, product designer, aerodynamic specialist, and bioinformatics engineer. (oddly enough it all ties together)

Hobby is writing software and just being a general maker.

>>465179

Go to a lumber mill or specialty lumber retailer if you want new wood or just look for old barn wood (they often used big heavy beams for construction and are only salvageable in short chunks perfect for table making). Wood that's already been aged would make it that much easier to get the look you want. And to stain it to look old just use a few different shades of the same colour so you get that blotchy look of aged wood. Also add a couple black patches to give it that oiled up look. There are lots of discussions on wood working forums on how to get an aged look with staining. That's your best bet.

Just make sure you don't use actual rail road ties. Leave that to stuff that will be used outside like a heavy duty platform to put a water cistern on.

>>465122
I am all for experimenting but I hate seeing people get frustrated with builds that don't pan out the way they intend and then they say speaker building is stupid or we are all hacks and don't know what we are talking about. etc. etc. etc. generally leaving a bad taste in that persons mouth and spreading more shit about the hifi industry being a bunch of jews. le sigh. Do something convinentional to start so that you can be proud of the build it will sound good and you will be driven to one up yourself. once you have that confidence go crazy and do odd builds!!

>>465273 <-don't listen to this guy.
You sir don't know what you are talking about when it comes to the material science of speaker enclosures. cherry, maple are not acoustically inert, infact they have a whole whack of even order harmonics that they exacerbate. Thus all you are doing is adding DISTORTION to you're build. The reason guys like me who KNOW what they are talking about suggest mdf is because it doesn't transmit vibrations nearly as efficiently as solid wood. The reason for that is due to it's resin and fine particulate material base it has a course crystalline structure that absorbs and dissipates mechanical energy (aka acoustical vibrations) versus transmitting them. A long chain stiff hard wood like maple has long chain polymers that carry that mechanical load and transmit it throughout the entire structure of the enclosure, great for instruments but terrible for a speaker cabinet. You want your enclosure to NOT transmit vibrational information as that will be distorted by the medium of the enclosure and be time delayed thus adding both resonance to the room adding even and odd order harmonics and creating destructive interference. MDF is a perfect inexpensive solution.

I use a unique system of composites and also viscoelastic polymers of my own creation.

Air tight is good too. You don't want pressure to escape where you haven't designed it to.

>>464959

You're best bet is to not make a table using railroad ties as they are soaked in creosote. Heavy oil product that has all sorts of nasty side effects.

https://en.wikipedia.org/wiki/Creosote#Health_effects -> for those that don't trust wikipedia just use google and check out the various studies done on it's effects.

Don't use this in your homes folks. Especially not for where you sit and eat.

>>464685

At the expense of an impedance spike, which depending on your amp, how accurate your crossover components are (and how well you construct it), and the actual frequency response AND impedance curve of your drivers can cause your virtual flat frq curve to go stupid. There's a reason you don't see those types of enclosures used all that often. They are highly unpredictable and impedance curve is just as important as on axis frequency response. Combine that with baffle diffraction and baffle step issues and you've got yourself a nice complicated set of issues.

----

- Another interesting tidbit I found in some of my research is that based upon room modes, and driver-room interactions the room itself can actually cause detectible impedance changes. These can be exacerbated depending on enclosure placement, crossover design and enclosure design. I was fascinated to look at efficiency gains and frq curve flattening that could be achieved by better understanding the room I am setting a system up in.

(pic not related but I love these horns, the plasma tweeter is one of the greatest drivers I have ever heard)

>>464723
Veneering is not easy and if you don't know how to book match, don't have the proper tools handy like a veneer knife and have never worked with it before you can end up with a glue covered ugly mess. In my professional opinion play with veneering on a flat sheet of cheap wood using inexpensive veneers from a good source (so you don't end up learning how to veneer with the crap you find at home depot/lowes/rona/harbour freight)..

I agree for most uses MDF is crap, but for speakers it is great as it's dense, flexible, absorbs vibrations fairly effectively, very inexpensive and easy to work with.


>>464609
It's 4chan and I was drunk. lol
Lots of speciality wood suppliers have baltic birch.

-Marine grade or furniture grade maple ply is still good enough as long as it is void free you are sailing.

>>464747
I have a degree in BSc in biochemistry, Masters in neurology, a Bachelors of Music in jazz, a minor in psychology. And took enough physics courses during my stint in univ to probably get another BSc.. I studied every book on the subject of acoustics and psychoacoustics I could get my hands on (still do to this day as there is always good info). Read everything I could find on forums written by guys like linkwietz, tom danley, earl geddes, and others. I subscribe to the AES journal and get as many papers as I can get my hands on. I also frequent Home theater Shack, AVS Forum, and DIY Audio, amongst a bunch of other places. I also dig up every research paper on music psychology I can find, including neuro science studies. I also spend a shit tonne of time with aerodynamics, fluid dynamics, and pressure systems. You would be surprised how much can be applied from an aerodynamic system or a pressure vessel and fluids under pressure to a speaker system in room. That's the next phase in this research is looking at the time domain aspect of pressure changes versus just frequency response curves in 2 dimensional space at time 0.

>>464230
tell that to those of us in the high end speaker system using baltic birch for the last 40 years without problems.

Also lrn2 speaker you fucking stupid inbred fuck stick. bass pound that to shit.. fuck you are dumb. also lrn2plywood grade.

to OP: your design is a waste of space, You have a pseduo adiabatic secondary resonant enclosure. In essence you are going to create a resonant pressure setup via the large chamber below your main enclosure but it will just create large resonance and impedance peaks (yes the enclosure can induce impedance spikes in the system which then needs to be dealt with via crossover design or some sort of additional zobel network...)..

I design, build and produce exotic loud speaker systems and do acoustic design for various architecture firms that create theaters, and recording studios.

>>430717

It's so sad what people will buy...

Clients that are ignorant assholes who don't want to learn anything and are just rich douche bags well, they end up with expensive 6n copper cables that are the size of a large boa and are totally useless.

I educated my clients and I'm not an asshole but some people just go through life with the attitude of "someone else should do the work and I just tell them because I'm the 'smart' one". So fuck em.

I have plenty of clients though who genuinely want their money's worth and they may not be super into music or hifi but have a willingness to learn or at least know what their money is being spent on or why their is money going to specific aspects of the project. Even some are dicks but if they show an interest by all means they will get a great setup.

Some people just choose to live a life of ignorance.

I also have other clients who like the idea of 50 thousand dollar speaker cables and 12 thousand dollar rca coax. They even know it does shit all but just can't help themselves.. So I set them up and usually give them a discount.

Hell I had a guy who knew it was all about the room and the speaker and had some great recordings and really did his research. And he saw a space I had done that had some MIT and Transparent cables (with their "boxes" of goodies). So I built him a set of wires with a nice zoebel in a fancy carbon fiber box that if I was a dick probably would have cost him 40 thousand or so. All told I think I charged him 1500 for those. Sure it's steep but I actually used high quality parts and told him they wouldn't do much though the speaker design he wanted had some weird impedance stuff happening so the zoebel helped with that.

Fun stuff.

>>430993

http://www.aes.org/