My first Project (help for a beginner)

[glicioto]

Hi fanatics,

I'm here to report my first ideas about my first DIY speaker design. I still wondering around the followin three options:
1) 3 ways = Peerless 830884 + Dayton RS52AN + Eton 26HD1
2) 3 ways = Seas L22RNX/P + Dayton RS52AN + Eton 26HD1
3) 2 ways = Scan Speak 8545 + Scan Speak D3004/6020.10 illuminator

The options reach comparable prices (for loudspeakers only). I'm more in favour of options 1/2 since they should give more bass response. Option 2 gives me some trouble with respect to 1 because Seas Woofer requires more Xover work (Peerless impedance is flat flat flat).
Option 3 is done using good drivers but it will go less down with bass response.

I'm on the way to get crazy, doubts and doubts are filling my head. In general terms my basic question is: is it better a 3ways system put togheter using mid/low class components (dayton midrange is sold in Italy at about 50 euro) or a two ways with much more expensive and deluxe pieces?

I look forward to find some helps on this forum: for sure many people more expert than my me (absolutely beginner) could enlight my thoughts and maybe show me problems I cannot see.

Notes:
Xover frequencies in case 1/2 are aroung 600 Hz; 3000 Hz. In case 3 Scan Speak Tweeter allows me to go quite low in order to avoid critical freqs for the woofer.

Ciao

Glicioto

[krips]

Are these options designs that someone has posted or you trying to design them yourself? It's often best to try someone else's design first as crossover design is challenging.

[glicioto]

The selection has been made by me. So I've not started cloning other solution. I know, having read many other posts, that experts tend to suggest to start from a kit. This could be fine, but in fact is hard to set to "mute mode" the desire to design something which is is really personal. I don't know what to think, clearly my question is not so new on this forum, but really if the DIY means copy a drivers selection, copy a Xover schematic, the only thing which remains is a huge wood work. If it is this, I would have built a table or a chair.

I may sound a little bit harsh, but I really would like to understand, and understanding is not easy if the only thing I'll do is soldering a project done by some body else. I know I know, everybody had to face this question going from beginner to expert...very difficult situation.

In any case my original query is still there, if somebody could at least start telling me the best rules to start to design a Xover with my option 1 or 3 it would be great. Thanks to everybody who will help.

Suggestion for the expert: why not trying to set up a step by step "how to". At least we will have something to begin with. There is nothing like that on internet.

Bye

[Willitwork]

I agree with krips, if you've never built someone else's design it would be a good idea to do so prior to launching yourself in constructing your own design especially when using such expensive drivers. Also I have never heard of anyone successfully design a 3-way Xover if they've never conceived a two-way circuit prior, it's a very complex process even with modeling software.

Unless of course you plan on using electronic crossovers. This makes the design of a 3-way Xover (or even 2-way) much more easy but requires a separate stereo power amplifier for each pair of drivers, thus 3-way = 3 stereo amplifiers or six mono amplifiers, plus various pre-amp configurations. This is massively costly and usually reserved for pro audio or wealthy audio extremists.

That said, by themselves decent quality electronic crossovers (Behringer) are not that expensive and if you intend to design your own passive Xover it would be a good idea to acquire one or two of those for testing purposes as they allow you to quickly change crossover slopes, frequency response, filter type, etc. without having to rebuild your passive circuit each and every time. Even though active crossovers and passive ones using same values do not typically sound the same you can be sure that if a speaker sounds awful at a given slope (for example) with the electronic crossover it will sound just as bad with the passive one.

[Andersonix]

Originally posted by glicioto
In general terms my basic question is: is it better a 3ways system put togheter using mid/low class components (dayton midrange is sold in Italy at about 50 euro) or a two ways with much more expensive and deluxe pieces?

A 2-way system is easier to get the crossover right. And simpler sounds better.

I don't really know what you consider 'low class,' 'deluxe,' expensive, etc., but why not start simple and work your way up in complexity, sound quality, and cost based on your own previous experience? You could try one of Zaph's or Dickason's (or many others') designs to get going.

And there's nothing wrong with 'cloning' someone else's proven design (and I'm NOT suggesting a kit, either). You'd be a fool not to take advantage of others' experience. In fact you're guaranteeing disappointment and frustration by diving in at the deep end, blazing your own trail, and running before learning to walk, and so on. But only you yourself know your own limitations....

[glicioto]

Ok Guys,

when I posted my question I was not simply asking are these drivers good??? Of course my selection was done considering a uniform SPL, low Impedance variation of the woofer and selection of Xover frequencies in order to let the three drivers to work in their better (i.e. flat rensponse area). This is valid in particular for the 3 ways option. Originally I though about a -18db slopes for all the cross Frqs. Clearly I discovered by my self that the woof-mid overlap is the most difficult to manage and design. All this assessment has been done considering the specifications given by manufacturer.

After the suggestions received I'll proceed like follows:
1) Study: I ordered another book to increase the theoretical knowledge
2) Verify: Try to understand the design solutions of other designers in order to see if I would have arrived to similar solution.

After that let me make last question: how much reliable are the manufacturer specifications, could you provide some hints to read them?

Last but not the least: please try to organize some guided step by step design starting guide...it would be really helpful for all the forum readers.

Ciao
Gli

[ultrachrome]

Originally posted by glicioto

After that let me make last question: how much reliable are the manufacturer specifications, could you provide some hints to read them?

Last but not the least: please try to organize some guided step by step design starting guide...it would be really helpful for all the forum readers.

Ciao
Gli

The point of these comments are to help ensure you are successful. It's quite easy to imagine your end goal but quite a different story to actually reach it.

I'd recommend finding independently published specs for the woofers you are interested in.

A possible option is buy the drivers of a well regarded design that is close to what you envision and see if you can replicate it yourself. You can always fall back to the published design for reference.

In theory, speaker design is pretty straightforward. Pick some drivers with complementary specs, throw them in a box, measure their response and construct a crossover to suit, remeasure, and tweak.

In reality the number of obstacles you'll have to overcome as a first timer can easily overwhelm. You have test equipment to procure, setup and debug, design software that is often far from intuitive and often unstable, and with the many steps that have to be taken, it is quite easy to miss one sending you back many steps.

Here is some thoughtful advice from sreten.