DIY audiophile 2-way drivers for ~$350? Please help>

[beady]

Hi all. New guy here who's had an interest in audio for a long time but never really taken the plunge.

I've built quite a few car audio enclosures before (sealed, vented, 4th order) and have a good Ryobi BT3100 tablesaw, jigsaw, etc and am quite capable of making about any type of enclosure, even quite complicated ones. I've also made up first order crossovers, but nothing spectacular.

What I want is to build are some really good speakers for listening to in a living room setting. Room is perhaps 12x20 (moving to a new house, not exactly sure of the dimensions off the top of my head). The drivers will perform everyday stereo TV sound duty also, and perhaps HT duty later on. I like most types of music except country. I suppose I lean more towards rock and electronic music if I had to pick genres. But, I want to be able to enjoy jazz/classical and other "detailed" music types also.

I was thinking of starting with a 2-way system with perhaps a 6"+ woofer (not set on that) and a tweeter. Don't have my heart set on any type of tweeter, so am open to suggestions. Was thinking I didn't want to go ported, as I was hoping for some "high end" speakers and want tight, accurate bass. Again, I could be persuaded differently though. I have a 12" sub and amp now, so the lower bass doesn't need to be of really high importance. However, I'm hoping to build something of much higher quality than my sub, so if I can get away without the sub and the resulting cleaner sound I will be happy. I figure $350 for the drivers (4) is about right?

OK, as to future plans, I want to build an amp. Been doing research and figure it will end up being an ESP P3A or AKSA. Maybe that will help in the driver selection? Looks like it will take a while to find all the components for the P3A (but I really like the idea of collecting everything and building it "myself") and I was thinking of building a gainclone kit to listen to the speakers with until I finish the P3A. Then, if it's a good idea, I was going to bi-amp the speakers with the gainclone running the tweets and the P3A running the woofers and use some active crossovers. Of course it will take yet more time to build the XO's..... Sorry, starting to ramble :-) Was getting at that perhaps I should not get too crazy on the passive crossovers if I am planning to go active? Then again I may be using them for a long while until I get the other amp and crossovers built so might as well go for good components, and if I do that I want to go higher order perhaps (4th order) and have Linkwitz transforms as well if I need them.

Alright, getting pretty long winded here so I'll try to wrap up. Since I don't have any test equipment I think I'd feel more comfortable perhaps following someone else's footsteps on driver selection and crossover components? I don't mind tweaking the crossover points to fit my room, but I'm not sure I'm up to designing the crossovers from scratch at this point and get a seemless integration bewteen drivers.

So, I'd appreciate any pointers for a guy starting out, and especially appreciate links or correspondence with drivers, volumes and crossover designs. I don't need box dimensions, how to fabricate, etc, just a volume to shoot for as I can calculate the rest. Please feel feel to tell me why I should go ported instead of sealed also :-)

Many thanks,

Mike

[morbo]

Alright, getting pretty long winded here so I'll try to wrap up. Since I don't have any test equipment I think I'd feel more comfortable perhaps following someone else's footsteps on driver selection and crossover components? I don't mind tweaking the crossover points to fit my room, but I'm not sure I'm up to designing the crossovers from scratch at this point and get a seemless integration bewteen drivers.

Wow! You are a true rarity - a DIY newebie who realizes his limitations! Normally first timers choose the 2 or 3 most expensive or fetishized drivers, and want to use them with a stock or textbook crossover. Your approach is sound, stick to a proven design and build it as specified, if you tweak anything make it the enclosure IMO. You can always mount the crossover externally for tweaking later if/when you understand what all the parts are doing. Here's a few links to start you off, some are kit vendors, others are just diyers who publish their designs:

www.zaphaudio.com
www.murphyblaster.com
www.creativesound.ca
www.madisound.com
www.northcreekmusic.com
www.selahaudio.com
www.theaudioworx.com
www.ellisaudio.com
http://www.partsexpress.com/projects...homeaudio.html

If you just want a 2 way floorstander or bookshelf, there are going to be a huge amount of options.

[tktran]

I'm usually the argumentative type, but I second everything morbo said. Good advice.

Here are some more links:

DIY plans free for personal use:
http://home1.stofanet.dk/troels.gravesen/
http://home.hetnet.nl/~geenius/
http://www.knology.net/~wesnor/
(previously mentioned)
http://www.zaphaudio.com
http://www.murphyblaster.com

A potential problem is that now you've got TOO many options, whereas previously you had none. :-)

This is when you'll probably want to ask people what they think of particular speakers, either by direct email for via the forums.

I've found the following forums very useful:
www.htguide.com
www.madisound.com
www.diyaudio.com
www.partsexpress.com

Personally, I use the ESP P3A with the "TroelAc Response 2.95" In medium sized rooms that are well furnished (carpets, drapes, soft furnishing) with placement away from walls, they sound excellent, and really sing!

I also built the Zaph Audio SEAS All Metal System, in floorstanding guise, and have had Dan Wesnor's Ella over at my place for a listen. All very good systems, with slightly different strong/weaks points.

I've also heard a Vifa P17/D25 designed by Dennis Murphy, but in entirely different setting and foreign source and amplifiers, so I'd hesitate to make a comparison.

If you'd like to know more, just ask, pop me an email, or visit my website.

Good luck, and have fun!

[rabbitz]

Build a GC by all means but it's not a fill in amp until you build something else. The sonics with a GC will surprise you and I liked it so much better than the P3A. The AKSA is in another league... very yummy and very special.

Yes, I've built them all with the AKSA in the main system and a GC in a secondary system with the P3A used in a test system and tunes for the workshop. I'm not knocking the P3A as it's a very honest design with good sound, but it just didn't do it for me. All a matter of taste.... one person's wine is another's poison and etc.

Your approach is very good to find the right speaker and you'll end up with something very good.

With the music you listen to, a vented would be better to get a lower F3 for use with out a sub. Do a search and there's plenty of threads on the pros and cons of sealed or vented.

Happy building.

[rcw]

There is an article on Rod Elliots site that I wrote called, "satellites and subs: the QB5 alignments". This points out that one of the major limitations of the cheap and simple satellite plus subwoofer system is that if you use a sealed box two way satellite with the usual 6-6.5 inch driver crossing over at around 80Hz, and 3kHz., you push the driver into quite serious non linear distortion at levels far below the standard 90db. with 20db. headroom spec. for a hi fi system, and since all of the distortion products fall in the upper bass lower midrange they are very audible.
A very good bang for your buck solution to this is to use a QB5 reflex alignment, and a suitable high pass filter. In a typical case the Vifa P17WJ has its excursion limited acoustic output capability increased by around 40 times, leading to a pair of these drivers being able to produce 110db. peaks without approaching their linear excursion limit, the difference this makes to the cleanliness of the sound needs to be heard to be appreciated.
The major drawback with this scheme is the anti port zealots that seem to hold sway in some audio circles these days, and who will no doubt declaim long and loud on the evils of ports.
A thing that continually amuses me is that audio types will dismiss as unsatisfactory an amplifier that produces more than a few thousandths of a percent of distortion, and yet happily drive a louspeaker system producing 20% distortion with it, whist claiming they can hear the lower superior performance of their pet amplifier, needless to say I am skeptical.

[tktran]

I agree with Rabbitz, amps can make a significant difference.

I had a NAD C320 that, on it's own, I thought was great. When compared to the P3A is sounded slightly warm and fuzzy in the midrange, with restricted lateral soundstage and mid-bass hump. I thought this meant it was 'inferior', so I promptly sold the C320.

I posted these findings on Madisound, and no-one seemed to have that impression of the C320.

So if I consider the flip side of the coin- in relation to the C320, the P3A has an expanded soundstage, clearer midrange and brighter treble. Now it sounds marvellous with my TroelAc Response 2.95.

But when I hooked up the ZaphAudio All Metal System, it immediately apparent that it was slightly bright. I thought "There must be something wrong with my new speakers"- after all, I hadn't followed John's plans exactly.

When it came for the P3A to go back to the ProAclones, I plugged up another amp to the "All Metal System." What the??! Suddenly the brightness was gone. Articulate midrange without any hint brightness, or as my partner called it- "the slightly metallic sound"

I always thought that an excellent amp will sound good with any excellent speaker and excellent CD player. But of course, how your stereo system sounds depends on all three, as well as room acoustics.

I hate to say it, but it seems to me now that system "synergy" is actually important- an amp that sounds excellent with one system may not sound good with another. The P3A is a stellar amp with the TroelAc Response 2.95, and I know at least one person who uses the P3A with the acclaimed Linkwitz Orion.

But when partnered with the All Metal System I found it unenjoyable.

beady,

The GC is a good amp, and the P3A may be an upgrade, sidestep or downgrade, but it's hard to tell without building both and listening.

As for me, I was looking to buy a budget Rotel amp for the All Metal System, but perhaps I should be looking for a NAD C370, which is what John was using when he fine tuned his crossover and concluded his design.

[rabbitz]

Originally posted by rcw
The major drawback with this scheme is the anti port zealots that seem to hold sway in some audio circles these days, and who will no doubt declaim long and loud on the evils of ports.
A thing that continually amuses me is that audio types will dismiss as unsatisfactory an amplifier that produces more than a few thousandths of a percent of distortion, and yet happily drive a louspeaker system producing 20% distortion with it, whist claiming they can hear the lower superior performance of their pet amplifier, needless to say I am skeptical.

Robert, there's no need for that sort of tone as this thread has been running fine with out that..... BTW, I like ported speakers. Everyone is entitled to their opinion and comments and I'm greatful that they do, as life would be too boring. If you can't hear the difference between amplifiers, that's fine, but don't ridicule those that state they can. They are doing it on the basis of what they hear and not forming an opinion from some measuring equipment.... they're happy and that's all that matters. All the amps I've found appealing do have higher levels of distortion and harmonics... maybe the tube guys know something besides watching something glow in the dark. I've heard amps with extremely low levels of distortion and found them too analytical..... not presenting the emotion and involvement of music . I think we need a bit less skepticism these days as it's up to the DIYer to try and form their own opinion. I know where the skepticism comes from, but leave it at that forum.

Originally posted by tktran
I always thought that an excellent amp will sound good with any excellent speaker and excellent CD player. But of course, how your stereo system sounds depends on all three, as well as room acoustics.

I hate to say it, but it seems to me now that system "synergy" is actually important- an amp that sounds excellent with one system may not sound good with another. The P3A is a stellar amp with the TroelAc Response 2.95, and I know at least one person who uses the P3A with the acclaimed Linkwitz Orion.

Spot on.... system matching is so important and a black art to get it right. If any one has a formula for matching, please pass it on The GC when used in one system, sounded er... quite ordinary, but in another hmmmm... great.

Cheers

[beady]

Wow, thanks for all the quick responses! Looks like it will take me quite a bit of time to go through all those links to see what is there.

Guess I'll have to do some more research on the gainclones; from what I had read I "thought" they didn't sound as good as the P3A's and AKSA's. I was thinking of buying and building one of the gainclone kits from ww.chipamp.com, is this a good place to buy from with quality components?

rcw, the QB5 alignment sounds interesting and worth looking into more. Googling, I found some other posts by you on the subject from last year, but other than that there does not appear to be a lot of information out there to find. I certainly didn't see any integrated designs for running a woofer like that with a tweeter matched to it that I might start out following for my project. Perhaps you could shed more light on the subject or point me in the right direction?

Unfortunately I am one of those ppl who likes to check out all the alternatives and really contemplate what I want to do before I make a decision, so I probably won't be choosing drivers or amps in the immediate future. Don't take that as me not appreciating the comments and information though, as I do :-) Also, my initial ideas usually take a while to finalize, and go through a couple of intermediate stages, but that's part of the fun in getting something "just right" that you really like, right?

[rabbitz]

Originally posted by beady
Guess I'll have to do some more research on the gainclones; from what I had read I "thought" they didn't sound as good as the P3A's and AKSA's. I was thinking of buying and building one of the gainclone kits from ww.chipamp.com, is this a good place to buy from with quality components?

It's a good valued GC kit with good components. I had a kit given to me and wasn't expecting much, a chip and a few resistors and caps I thought pfft, and was shocked and blown away with it. What I said about amps is only my opinion any way. Build them and make up your own mind... all part of the fun... and don't listen to an old fart like me

If you want to know a bit more about the AKSA, have a look at their forum.... lot of happy builders and owners over there.
http://www.audiocircle.com/circles/v...6afd7adacc4bbe

[morbo]

Unfortunately I am one of those ppl who likes to check out all the alternatives and really contemplate what I want to do before I make a decision, so I probably won't be choosing drivers or amps in the immediate future. Don't take that as me not appreciating the comments and information though, as I do :-) Also, my initial ideas usually take a while to finalize, and go through a couple of intermediate stages, but that's part of the fun in getting something "just right" that you really like, right?

Makes perfect sense, I am the same way. Just beware of analysis paralysis, there are few bad choices out there, and its very easy to obsess over minutae.

rcw, I am also interested in your article, as I have arrived at something similar just from fooling around with vented speakers and DSP... though I've never tried adding a sub, just used it to make a increase power handling in a vented speaker. One thing I do wonder though, is how you go about bringing in the subwoofer with a symmetrical slope that matches the rolloff of the satellite?