Future (active?) recommendations please, for a noob

[jostenmeat]

I don't even know where to begin. Making a set of three towers is one of three competing upgrade possibilities for me, and I'm trying to learn more to make a better decision. I would like to keep it under $2k in total costs for everything. $1.5k would of course be much better (as this is right about what the other two upgrade paths would each cost). This wouldn't happen for months.

I am interested in trying an active system. I can dedicate my 7ch amp to power the towers if they are to be 2-ways, and then have my receiver power all of the surrounds. I suppose if I wanted to do 3-ways, I can just add a 2ch amp. Perhaps a Crown XTi1000. As for the device to provide the xovers, what is recommended or even capable? DBX, DEQX, DCX, say what?!

However, I'm not against passive designs either, as that's all I've really heard, and there's some great stuff out there.

I will not design my own. Kits of course would be the easiest, and such recommendations are very welcome for obvious reasons. I am willing to follow plans, otherwise. I have absolutely no idea how hard it is to build passive xovers, and how much the caps/parts end up costing.

What I would like in my speakers are firstly dialogue intelligibility, or as TLS puts it, no chestiness, no shout, perhaps keeping the xover away from the critical dialogue passband. Second would be to have excellent dispersion or offaxis response. Third would be capable midbass, and I presume that I'd want at least a 7" woofer, if not larger (I do not know if my stated budget would even allow for this). Fourth would be having a voicing that is not too far off from the signature of PSB. Fifth would be to not give up too much sensitivity and/or efficiency from what I presently enjoy (which is currently 91db/2.83/m anechoic).

Yes, going active, with necessary equipment, and additional amplifier, will likely blow the budget. But by how much will it blow the budget?

Are the ER18s the WTG? Would the affordable TriTrix not provide quite the upgrade? (Oh, I'm coming from PSB T55s.) Mini Statements that I think jinjuku was looking at? I don't mind the sound of ribbons, but since I put offaxis dispersion as nearly the highest priority, I think I should stick with domes?

Where to begin?! Thanks for reading!

 

[GranteedEV]

The Zalytron Zeus kit looks rather nice as well. I've never seen anyone's build of it. The driver choice is as good as it gets, that's for sure.

The Jantzen DTQWT HES looks cool too.

 

[Swerd]

I have no experience with active crossovers, so I can't comment about any of those devices. I think a good crossover design is independent of whether it is passive or active. Let price determine which way you go. As far as I can tell, people who have active crossovers are always tinkering with them. If the crossover design is good to start with, this should not be necessary.

Compared to building and finishing cabinets, I think building a passive crossover is much easier. As an example for price for passive components, look at the crossovers and parts list for the ER18 MTM.

What I would like in my speakers are firstly dialogue intelligibility, or as TLS puts it, no chestiness, no shout, perhaps keeping the xover away from the critical dialogue passband.

Chestiness, as in a male radio station announcer's voice with too much bass boost, comes from an exagerated midbass in the 70-120 Hz range in a speaker. Keep Qts less than 1.0, preferably at 0.7 or lower, and you'll avoid chestiness. I'm talking about cabinet bass tuning here, and not crossovers.

Shout, if TLS means it the way I understand it, comes from a speaker without baffle step compensation (BSC). This results in an elevated response in the roughly 500-1000 Hz range. BSC is often built into a passive crossover as a separate circuit, but there are several different ways to accomplish this depending on the size of the woofers and the width of the front baffle. BSC also allows a smaller woofer to sound like it has better bass response, but it comes at the expense of lower sensitivity.

If you keep the crossover point at 2500 to 3000 Hz it will be well above the dialog passband, and most primary music tones. But this also comes at the expense of some other things you want. It requires a smaller woofer. A crossover at 2000 can also work well, if it is flat and if careful attention is paid so that woofer and tweeter are not out of phase with eachother within one octave of the crossover point.

Second would be to have excellent dispersion or offaxis response.

Most people think about tweeters when they talk about dispersion and off-axis response. But the off-axis response of a woofer (in a 2-way) just below the crossover point is actually more important. Read this article titled Choosing the Crossover Frequency. It does a better job explaining this than I can.

There are several other good articles on that Speakerbuilder.net website. I found them very helpful when I was getting started.

Third would be capable midbass, and I presume that I'd want at least a 7" woofer, if not larger (I do not know if my stated budget would even allow for this).

A 7" woofer will probably do very good for the bass, but crossing it over to a tweeter will have to be done at a lower frequency than for a smaller woofer. This will be more in the portion of the midrange (the human voice passband) where our ears are most sensitive. As an example where this was done successfully, the ER18 MTM uses two 6.5" woofers (for more bass response than with one) crossed over at about 2500 Hz.

Fourth would be having a voicing that is not too far off from the signature of PSB.

Better to aim for a flat frequency response across most of the audio range. The hardest region to achieve this is, of course, where the crossover acts.

Fifth would be to not give up too much sensitivity and/or efficiency from what I presently enjoy (which is currently 91db/2.83/m anechoic).

I wouldn't worry too much about this, that's what big amps are for. 87-88 dB is very useful in my experience. I also wonder just how real that claim of 91 dB sensitivity is. Many manufacturers are known to exaggerate sensitivity ratings.

Are the ER18s the WTG? Would the affordable TriTrix not provide quite the upgrade? (Oh, I'm coming from PSB T55s.) Mini Statements that I think jinjuku was looking at? I don't mind the sound of ribbons, but since I put offaxis dispersion as nearly the highest priority, I think I should stick with domes?

As a guess, the TriTrix may not have drivers of the same quality as the T55. This is only a guess, I've not heard them.

What does WTG mean? If you mean ER18s are the Ones To Get, I'd have to agree .

Don't worry so much about the off-axis dispersion smaller ribbon tweeters. It's the woofer's dispersion, or lack of it, below the crossover frequency that generates a speaker's wide dispersion and ability to cast a wide image.

 

[jostenmeat]

GranteedEV, thanks so much for the suggestions. I am excited for the little bits of knowledge I may pick up in the near future when I investigate further.

Swerd, that is one of the best posts I've received on my behalf in recent memory.

I appreciate the clarity of your teachings about the importance of the xover point, and its entirely important relevance to the questions/concerns/ideas that I have.

(Xover points, lobing points, comb filtering, etc, it's interesting that it's always about getting it as far as the midrange as possible, whether that is lower and away in the case of horiz mtm lobing, or higher and away in the case of AT screens, and now in the case of xover points between tweeter and mid.)

Little things outta the way: I have the impression* that PSB is not one of those that exaggerate. I stated the anechoic number, but on their site, right below that spec is the "in room" number at 93/2.83/m. I have the impression that their line of speakers (for their price point) have better than average efficiency and power handling. Subjective (worthless) guess, but it is my impression nevertheless. WTG means way to go, but your guess is close enough, haha. Hm, so if you say they are the ones to get, then . . . do I just quit my research now?!? hahaha. I am half joking, but that also means half-not-joking too.

OK then, as of right now the ER18s are the forerunner, until something better comes my way. I don't have the time as of this very moment to look further into Granteed's recommendations, but the cursory google hits show someone saying that one of them sound very different from the Salks (which I assume the ER18s will sound like). I will have to see what the outlay for the ER18s are, and just how much savings there are from something like the SongTowers. How much better, if at all, are the ER18s? I should state that these will be filling higher volume HT duties too, for many viewers, in a wide seating arrangement, and so I think the larger woofers with this design could very well be the ticket.

I will not care about finish. I am atm leaning towards unfinished, so that if I ever want to sell them, the buyer can do whatever they want with them at that point. Sort of how I see it with my sub. After all, the front three will not be visible whatsoever. Or if they ever come out of hiding, I can choose something at that point.

Lastly, do two smaller woofers provide the same amount of midbass as one larger one with the (hypothetically) exact same cumulative surface area? I assume not (depending on the specific frequency), and I bet that's a terrible question, as too many other things probably come into play. But if there is an answer that is not too complex, it would be greatly appreciated.

Heck, I'd be happy to have any SEAS drivers of any kind at all in my rig, but to have them be dual 7" per speaker is sounding pretty fun right now. Ok, I am also wondering what kinds of diminishing returns there are by going active (in terms of everything, including time, learning curve, cost, source material being played back, etc).

 

[Swerd]

OK then, as of right now the ER18s are the forerunner, until something better comes my way. I don't have the time as of this very moment to look further into Granteed's recommendations, but the cursory google hits show someone saying that one of them sound very different from the Salks (which I assume the ER18s will sound like). I will have to see what the outlay for the ER18s are, and just how much savings there are from something like the SongTowers. How much better, if at all, are the ER18s? I should state that these will be filling higher volume HT duties too, for many viewers, in a wide seating arrangement, and so I think the larger woofers with this design could very well be the ticket.

The Zalytron Zeus, an expensive kit, uses the same SEAS W18 woofers as in the Salk HT1, HT1-TL, Ellis 1801-TL, HT2, HT2-TL speakers. In the HT-3 the W18 is used as a midrange. It's an excellent and expensive driver. The Hiquophon OW2 ¾" dome tweeter in the Zeus is the same tweeter as in the Ellis 1801-TL and the Songtower. Any difference in sound between the Zeus and the Salks will be due to the crossover.

Do you have a link to that google hit you mentioned where someone says that it sounds very different from the Salks? I don’t know who designed the Zeus, and I've never heard them. Given the price difference, I'd definitely go with the ER18 MTM. I have heard it side by side with Salk HT2-TLs, and they are very close. Price $4200 for the finished Salk vs. $600 for the ER18 parts. A sheet of MDF should cost under $50. You do the math.

Lastly, do two smaller woofers provide the same amount of midbass as one larger one with the (hypothetically) exact same cumulative surface area? I assume not (depending on the specific frequency), and I bet that's a terrible question, as too many other things probably come into play. But if there is an answer that is not too complex, it would be greatly appreciated.

A smaller woofer usually has a higher resonance frequency (Fs) than a larger one. That determines the cabinet tuning frequency. Two smaller woofers can produce plenty of bass, more than from one similar smaller woofer, but their Fs is still the same. How that affects midbass is a good question. It varies with the woofers you are comparing. I'd rather go with two smaller woofers in an MTM design, and add a subwoofer for deep bass, instead of going for a 3-way. The ER18 MTM has an F3 (frequency where response is down by 3 dB) of 35 Hz can deliver useful bass as low 31 Hz. To get a 3-way that goes as low as 20 Hz, you'll pay lots of extra money.

 

[GranteedEV]

The Zalytron Zeus, an expensive kit, uses the same SEAS W18 woofers as in the Salk HT1, HT1-TL, Ellis 1801-TL, HT2, HT2-TL speakers. In the HT-3 the W18 is used as a midrange. It's an excellent and expensive driver. The Hiquophon OW2 ¾" dome tweeter in the Zeus is the same tweeter as in the Ellis 1801-TL and the Songtower. Any difference in sound between the Zeus and the Salks will be due to the crossover.

Indeed, the Zeus crossover may make or break it. It's beyond mysterious.

The DTQWT otoh looks amazing. The only thing I would change about it is if i did go with the 3-way build(it's sold as a 2-way TQWT build with plans for the 3-way DTQWT), i'd cross that portion active and use a higher lowpass slope. I want to hear one really badly.

 

[Swerd]

Indeed, the Zeus crossover may make or break it. It's beyond mysterious.

I'm not sure I understand why you say it's mysterious.

It is clearly not designed by Dennis Murphy. If it were, it would say so on the Zalytron site. I do know for certain that Dennis does not work with Zalytron. I suspect there may have been some dispute in the past, but Dennis is too much a gentleman to say anything bad of anyone, whether they deserve it or not. Once several years ago, when I was building my CAOW1s, I asked him if he preferred buying tweeters from Zalytron or Dave Ellis (the only two US dealers for Hiquphon), and he answered, "Dave Ellis, definitely" without hesitation.

All of Dennis's good speaker designs share a flat frequency response and phase coherence through the crossover range, and as a result, they all share a characteristic sound. I wonder if the crossover of the Zeus can compete. Unless I hear one, I'll never know. Considering the high price and the numerous alternatives to the Zeus, I suspect I probably won't.

 

[GranteedEV]

I'm not sure I understand why you say it's mysterious.

I wonder if the crossover of the Zeus can compete. Unless I hear one, I'll never know. Considering the high price and the numerous alternatives to the Zeus, I suspect I probably won't.

that's why i say it's mysterious. No measurements, no subjective opinions... no detailed information... just mysterious. It's unknown who designed it too.

that doesn't necessarily imply it's bad at all, but it'd an unknown.

 

[Swerd]

that's why i say it's mysterious. No measurements, no subjective opinions... no detailed information... just mysterious. It's unknown who designed it too.

Thanks. Somehow, I thought you knew something clever and wonderful that I didn't .

And while we're speaking poorly of speakers we've never heard, I also wonder about the Zeus cabinet design. They claim is that it's a transmission line, but because it's about 5 years old, I doubt if it was designed using Martin King's methods. Before his modeling methods became widely available, TL design was trial and error with real wood. A select few people were good at this, but most who tried settled for "good enough" without really getting there. With King's methods, all the trial & error is done on the computer, and the predicted results are usually highly reliable.

So for the Zeus, both the crossover and the cabinet design are mysterious.

 

[GranteedEV]

Thanks. Somehow, I thought you knew something clever and wonderful that I didn't .

And while we're speaking poorly of speakers we've never heard, I also wonder about the Zeus cabinet design. The claim is that it's a transmission line, but because it's about 5 years old, I doubt if it was designed using Martin King's methods. Before his modeling methods became widely available, TL design was trial and error with real wood. A select few people were good at this, but most who tried settled for "good enough" without really getting there. With King's methods, all the trial & error is done on the computer, and the predicted results are usually highly reliable.

So for the Zeus, both the crossover and the cabinet design are mysterious.

Indeed very mysterious. I wonder if anyone's ever built it.

Have you heard the jantzen HES by any chance? BTW i just noticed the guy has in the past made his own attempt at your reinvented west coast sound

http://www.troelsgravesen.dk/JBL_L100.htm

creepy

 

[Swerd]

Have you heard the jantzen HES by any chance? BTW i just noticed the guy has in the past made his own attempt at your reinvented west coast sound

http://www.troelsgravesen.dk/JBL_L100.htm

creepy

I'm pretty sure that I've never heard any Jantzen driver. I've been to a number of local DIY speaker builder meets, and I don't think I ever ran into a speaker with Jantzen drivers. It's true DIY builders follow fashions and trends just like anyone else, but I think it might have been Jantzen's high prices that made most builders avoid them.

I've also never seen any decent high-efficiency designs done by DIY builders. I have seen one or two high-efficiency designs that were very expensive and sounded terrible. All the builders I know tend to believe that different speakers and crossovers make a large difference in sound quality, and that amplifiers make little if any difference compared to speakers. Among that group of people, it is unlikely to find someone advocating vast benefits from low-powered vacuum tube SET amps and the very sensitive speakers they require .

 

[GranteedEV]

I'm pretty sure that I've never heard any Jantzen driver. I've been to a number of local DIY speaker builder meets, and I don't think I ever ran into a speaker with Jantzen drivers. It's true DIY builders follow fashions and trends just like anyone else, but I think it might have been Jantzen's high prices that made most builders avoid them.

I've also never seen any decent high-efficiency designs done by DIY builders. I have seen one or two high-efficiency designs that were very expensive and sounded terrible. All the builders I know tend to believe that different speakers and crossovers make a large difference in sound quality, and that amplifiers make little if any difference compared to speakers. Among that group of people, it is unlikely to find someone advocating vast benefits from low-powered vacuum tube SET amps and the very sensitive speakers they require .

It's not so much a matter of the amps themselves, but the ease with which to do it. Unless I'm mistaken, high efficiency speakers would have superior dynamic range because there is less need for high thermal power handling.

I figure if it only takes ~60w in 8 ohms to get to 105 db at a good seating distance (IE like ~8ft away), there will be less thermal compression than if it takes 10 times as much. I figure that these speakers will have the dynamic range I need. To drive the HT2-TLs (88db/2.83v/m) to the same peak SPL you would an amplifier capable of ~600 watts into 4 ohms! So average sensitivity speakers require high power amplifiers just as low power amplifiers require high efficiency speakers. The general opinion seems to be that "watts are cheap" and people are free to feel that way.

Now at the end of the day linear throw is still another factor to consider when it comes to the SPL factor, but i think a higher efficiency is a good place to start.

I realize that for most, SPL capability isn't very important. Personally I want my next speaker system to not only sound excellent in many facets, but also excellent when the power is turned up. As you and I agree, the crossover, box(or lack thereof) and drivers at the end of the day will be the major factors to determine the sound. The efficiency itself doesn't necessarily have much to do with that.

Plus if it's tube friendly, I feel comfortable for a fact that it's going to be solid state friendly. I honestly have doubts at times of whether my receiver is able to drive my speakers to their full potential, which are 6 ohms with a few 4 ohm dips... pretty much an easy load but still not a cinch.

I do agree that it is on the expensive side, but it makes sense considering he had to get those midrange drivers custom made by seas to his specification. It's also not like there's many alternatives in this category... as you said. The other one I'd love to hear is the Salk/Jeff Bagby Pharos... which retails for like $9000 and the gedlee stuff, which also gets rather expensive quickly and visually at least doesn't appeal to me.

Perhaps I should attempt his preliminary design which used off the shelf drivers for a total cost around $250.

 

[jostenmeat]

Do you have a link to that google hit you mentioned where someone says that it sounds very different from the Salks? I don’t know who designed the Zeus, and I've never heard them. Given the price difference, I'd definitely go with the ER18 MTM. I have heard it side by side with Salk HT2-TLs, and they are very close. Price $4200 for the finished Salk vs. $600 for the ER18 parts. A sheet of MDF should cost under $50. You do the math.

Regarding the Zeus comment, it was some random guy on a forum, I do not think it's worth chasing down right now. If the HT2-TLs are the closest thing to ER18s, wow this build has a lot of value! I'm already getting excited, haha.

Regarding the MDF, is it ok to use other materials in this case? Like Baltic Birch ply, or any other possible alternatives to know about? I don't even know how much BB actually costs, though I'm sure it can't be too cheap. Thanks.

Over this weekend, I hope to read and reread Skyline's instructions, and I also hope to write out all of the expenses on a list. If only for fun. I see the woofers are $81.40 a piece.

A smaller woofer usually has a higher resonance frequency (Fs) than a larger one. That determines the cabinet tuning frequency. Two smaller woofers can produce plenty of bass, more than from one similar smaller woofer, but their Fs is still the same. How that affects midbass is a good question. It varies with the woofers you are comparing. I'd rather go with two smaller woofers in an MTM design, and add a subwoofer for deep bass, instead of going for a 3-way. The ER18 MTM has an F3 (frequency where response is down by 3 dB) of 35 Hz can deliver useful bass as low 31 Hz. To get a 3-way that goes as low as 20 Hz, you'll pay lots of extra money.

Ah thanks. 35hz is pretty darn excellent for a 2-way speaker. If I ever build these, I look forward to trying a 40hz xover with them (I currently use 60hz with front three).

edit: I just contacted a couple of friends who have previously expressed some interest in buying my old speakers, hehe. Even if I let them go for better than any classified price ever, I still would pay very little out of pocket for this kind of project. Neato.

I do agree that it is on the expensive side, but it makes sense considering he had to get those midrange drivers custom made by seas to his specification. It's also not like there's many alternatives in this category... as you said. The other one I'd love to hear is the Salk/Jeff Bagby Pharos... which retails for like $9000 and the gedlee stuff, which also gets rather expensive quickly and visually at least doesn't appeal to me.

Perhaps I should attempt his preliminary design which used off the shelf drivers for a total cost around $250.

I forgot about the Gedlee stuff, which I know almost nothing about. Which kit would you recommend from here?

http://www.gedlee.com/Loudspeakers.htm

 

[GranteedEV]

I forgot about the Gedlee stuff, which I know almost nothing about. Which kit would you recommend from here?

http://www.gedlee.com/Loudspeakers.htm

Whatever you can afford... the harper is what I should even consider "affordable"...the abbey is what I would desire... and summa is what i really really really want.

They're all ugly though and I like proper towers.

 

[jostenmeat]

Whatever you can afford...

Ok. You know the kits are not that* much cheaper than the prebuilt and pretested. Hm. I suppose, even as a kit, the Nathan would be the most I could afford (and that's at the top end of budget) when getting three of them, assuming that they would sell one individually to begin with. The Harper, OTOH, would come under budget, as 1.5 kits.

*I assume the kit prices are for a pair of speakers, and not an individual speaker.

 

[Swerd]

Regarding the MDF, is it ok to use other materials in this case? Like Baltic Birch ply, or any other possible alternatives to know about? I don't even know how much BB actually costs, though I'm sure it can't be too cheap. Thanks.

I don't see any reason why you couldn't use baltic birch ply instead of MDF in the ER18 MTM cabinet. But I also don't see any reason why it would be better than MDF.

• Baltic birch or other void-free plywood costs more than MDF.
  
• Baltic birch is lighter than MDF of the same thickness. Cross-bracing matters more than the difference in weight.
  
• Baltic birch can hold screws better than MDF.
  
• MDF has a smoother surface than baltic birch, making it easier to prepare for veneer or other finishes.
  
• Baltic birch, or any plywood, leaves the ply layers visible on the edges of butt joints. If not treated properly, they can be seen through paint or veneer. It is better to cut mitered edges at a 45° angle to hide the layers. This can be more difficult for a DIY builder with limited woodworking skills.

 

[jostenmeat]

I don't see any reason why you couldn't use baltic birch ply instead of MDF in the ER18 MTM cabinet. But I also don't see any reason why it would be better than MDF.

Thanks Swerd! Well, in my case, I don't mind lighter weight! Hahaha. I really got a workout on my last two projects and none of those had MDF involved. Stuff is so darn heavy, I hear that it's nastier to work with(?), and it just simply doesn't have the appeal that wood does for me. But, if I get sticker shock with good ply, maybe I'll do MDF after all.

I know I'll sound even more insane, but I really do want to try height speakers sometimes. So far as I know, they do not need to be very capable speakers, but I do think it would be best to voice match them. Would the below be good candidates? (For bookshelves, there are probably few to none that are "similarly voiced" to the ER18s?) I admit I wouldn't mind spending less or reducing the amount of work (but I am definitely not crossing my fingers on that one). Thanks. Oh, side question regarding height speakers: what kind of bracket/mount would anyone recommend to install on the speaker itself?

http://www.audioheuristics.org/projects_gallery/ER18DXT/ER18DXT.htm

 

[GranteedEV]

(For bookshelves, there are probably few to none that are "similarly voiced" to the ER18s?) I admit I wouldn't mind spending less or reducing the amount of work (but I am definitely not crossing my fingers on that one).

Voice matching does not require the same drivers. A pair of MBOWs or CAOWs would probably :voice match: the ER18s in the sense of timbre as they were designed with the design same goals. They may cost more (or less?) though. I want to build Dennis Murphy's Usher 2-way..

 

[jinjuku]

I don't even know where to begin.

Start with an in-expensive two way. One of a known design were you know the passive X-Over parameters. Something with a simple network (lr2).

 

[jostenmeat]

Start with an in-expensive two way. One of a known design were you know the passive X-Over parameters. Something with a simple network (lr2).

Thanks for the advice, but since I've already decided that I am going to use a proven design, it will all be a matter of following instructions carefully. Therefore, I'd like to build the best speakers that I can, right now, whatever the design. I do not want upgraditis 2 weeks after the build's completion. To be quite honest, the last time I enjoyed the HT, my PSBs were sounding really darn good. I just want better sometimes. One day, I'll try reading more about active setups. I bet I'll last 15 minutes before my head blows up.

I'm reading through Skyline's thread right now, but I have to stop now. I'm presently at post #62. Will continue later. All I know from my sub kit build, and that thread only reinforces it, is to just order *everything and more* when ordering the parts. I see that pan head screws and gasket tape will be included for now. We will see if this is the path I do take. I've been pining over a colorimeter and CMS for years now.

What are recommended local resources for finding the right parts for the xover, assuming that PE or any other online retailer doesn't have them? Though the stated 10% allowable variance on values does seem to be very forgiving, I'll still try to aim for dead center. I'd like to ask what the proper adhesive would be to mount these parts, but I'm pretty sure Alden's book might tell me, which I have just now ordered as that was recommended by Swerd in yet a different thread. That should really help limit the number of unnecessary and stupid questions I might ask.

I will either reread soon, or simply ask if I can't find the answers, but regarding the ER18s, I'd like to know if the front baffles are absolutely necessary, or very highly recommended for a performance reason or other. I am also curious as to the reason for the horiz tweeter offset, perhaps it has to do with lobing/interference angles.

Does anyone have major objections to exclusively using Neutrik connections on the speakers?