Hey guys I have been keeping my eyes out for a set of speakers for a speaker build. I found these Tesla ARO 666 8ohm 5w speakers, complete with tweeters.
I have built some subs etc, and I am I pretty good carpenter, but have little technical experience with speakers.
I would consider and open baffle or horn type design, with or witout the tweeter.
These will be used (hopefully) as my main monitoring speakers for my computer/TV.
Not looking for crazy volume, but I would like to have half decent bass response. I know nothing replaces a seperate sub, I do have one to hook up when needed.
I have some specs here for it, from an old PDF. It's on page 4, http://www.classicaudio.ru/tech/tesla70s.pdf
I also found some specs from other forum members here,
Qts:0.81
Vas:17.3L
Fs:93Hz.
Re:7.7ohm
Le: ?
Xmax: ?
Qms: 4.79
Qes: 0.98
Pe: 5W (as per back of magnet)
Sd: 268.66cm^2
SPL: 94dB @1W, 1m.
Let me know what you think!
I have built some subs etc, and I am I pretty good carpenter, but have little technical experience with speakers.
I would consider and open baffle or horn type design, with or witout the tweeter.
These will be used (hopefully) as my main monitoring speakers for my computer/TV.
Not looking for crazy volume, but I would like to have half decent bass response. I know nothing replaces a seperate sub, I do have one to hook up when needed.
I have some specs here for it, from an old PDF. It's on page 4, http://www.classicaudio.ru/tech/tesla70s.pdf
I also found some specs from other forum members here,
Qts:0.81
Vas:17.3L
Fs:93Hz.
Re:7.7ohm
Le: ?
Xmax: ?
Qms: 4.79
Qes: 0.98
Pe: 5W (as per back of magnet)
Sd: 268.66cm^2
SPL: 94dB @1W, 1m.
Let me know what you think!
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with Qts of 0,81 horn is impossible ;
go to OB , if that is your second choice ....
but - you'll need bass helper(s) - same on OB or in some sort of box
go to OB , if that is your second choice ....
but - you'll need bass helper(s) - same on OB or in some sort of box
OK I slaped together some quick baffles out of some scrap 1/2" birch ply, I wanted to make sure they worked right before I spent too much effort.
The result? Very nice indeed. I've watched a few movies and listened to a few tunes, I like them.
Makes TV shows filmed outside, sound like they are outside, lot's of ambiance, but smooth.
The bass is nice smooth and musical, acoustical. Nothing crazy, but I was after a nice sound, not huge thump. The have lot's when you 3' away.
I suspect my computer monitors are helping the bass a bit, kinda extending the baffle.
I may now do something a little nicer with them, maybe a grill, or solid exotic wood of sorts. I have time to dwell on that thought.
All in all a nice little project, 🙂 I needed that what with all my other intensive hobbies. lol
The result? Very nice indeed. I've watched a few movies and listened to a few tunes, I like them.
Makes TV shows filmed outside, sound like they are outside, lot's of ambiance, but smooth.
The bass is nice smooth and musical, acoustical. Nothing crazy, but I was after a nice sound, not huge thump. The have lot's when you 3' away.
I suspect my computer monitors are helping the bass a bit, kinda extending the baffle.
I may now do something a little nicer with them, maybe a grill, or solid exotic wood of sorts. I have time to dwell on that thought.
All in all a nice little project, 🙂 I needed that what with all my other intensive hobbies. lol
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Fortunately, I didn't get that memo 😉, but at 160+ L for just a 1/4 WL stub, they're a bit large for the intended app. Still, with only 5 W and most likely just a minimal Xmax...........
GM
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Thanks for the feedback and effort.
So I'm listening to these this morning with a fresh set of ears. I'm sold. I should have built a set of these long ago.
I've actually heard new things in songs I have heard hundreds of times, this is something I usally only experience with decent Sony headphones and my Cmoy 🙂
I can hear other band members sing in the backround. Spooky at times, have to look over my shoulder. lol
I really like how there is no box to colour the sound.
I also like how it smooths out the treble from my HTPC a bit as I listen to MP3 type media.
So I'm listening to these this morning with a fresh set of ears. I'm sold. I should have built a set of these long ago.
I've actually heard new things in songs I have heard hundreds of times, this is something I usally only experience with decent Sony headphones and my Cmoy 🙂
I can hear other band members sing in the backround. Spooky at times, have to look over my shoulder. lol
I really like how there is no box to colour the sound.
I also like how it smooths out the treble from my HTPC a bit as I listen to MP3 type media.
ARO666 is an old speaker, built by Tesla Valasske Mezirici, Czechoslovakia, in the sixties. It is not a woofer, it is a "midrange" speaker intended for use in large AM/FM radios. Its frequency range is 60 - 10000 Hz, rated input power only 5W, peak power 6W. Sensitivity is high 94dB/m/W.
OK, I was thinking of floor standing speakers and a bit longer listening distance. For up close with high Qts drivers, OB or ~aperiodic (leaky sealed cab) is best overall. Still, with a relatively high Fs you do run the risk of over-driving them with some music and of course movies even at low SPL, so a good idea to use EQ to roll them off below ~65-75 Hz. Being so close, ideally you want the tweeter to be as close to the woofer as practical.
GM
GM
Alright I rolled the 62 on my EQ down a little bit.
Quick question: Is it as much of a concern to have everything below the Fs turned down, or specifically Fs frequency?
I know that this speaker responds very little below 60, but moving the 31 slider does change it a little bit.
I'm not trying to squeeze more bass, it's more of a general question.
Quick question: Is it as much of a concern to have everything below the Fs turned down, or specifically Fs frequency?
I know that this speaker responds very little below 60, but moving the 31 slider does change it a little bit.
I'm not trying to squeeze more bass, it's more of a general question.
Ok so I downloaded Hornresp to play around with. I am going to see what I can find for suitable woofers, oh yes the wheels are turning..,...,..,..
As I previously noted, everything below ~0.7*Fs and sometimes even a bit higher. The exceptions would be a ~aperiodic (well stuffed vented cab) where the cab's acoustic impedance will protect it. A ~0.7 Qtc sealed alignment will limit excursion, but will still cause a certain amount of extra VC heating (distortion) at higher power, raising its effective Qtc as the trade-off.
Since this driver's Qts is higher than ~0.7 though, sealed isn't a viable option since it will require an extremely large cab just to get its Qtc down to the driver's Qts.
GM
Ah gotcha, Yes your right, (about the specs) I am now just understanding how to apply the info you gave me. I thought it was possible to build a 160L enclosure, 😉
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Built some bigger baffles to help out the bass some.
Put some dampening on the back.
I used the golden mean wherever possible.
I am thinking about adding one of those rear braces.
After a quick sand tomorrow, I will cover it in Burlap for now.
I also have a 6" x 8" plate I might add over the speaker at the back, you may have seen them.
As expected, they sound really, really good. I picked up a load of bass. Well worth the extra size. I will rearrange me area later on so I can spread them out a bit.
I made a 20 degree angle to it, to help project the sound at ear level. I thought all day and night about building a 48" tall folded one. I'm glad I went this route, honestly it's fine.
It's great to use up some scraps, makes for a "free" project. Takes a little longer to peice something together, but hey it's a hobby. The reward is worth the time.
Put some dampening on the back.
I used the golden mean wherever possible.
I am thinking about adding one of those rear braces.
After a quick sand tomorrow, I will cover it in Burlap for now.
I also have a 6" x 8" plate I might add over the speaker at the back, you may have seen them.
As expected, they sound really, really good. I picked up a load of bass. Well worth the extra size. I will rearrange me area later on so I can spread them out a bit.
I made a 20 degree angle to it, to help project the sound at ear level. I thought all day and night about building a 48" tall folded one. I'm glad I went this route, honestly it's fine.
It's great to use up some scraps, makes for a "free" project. Takes a little longer to peice something together, but hey it's a hobby. The reward is worth the time.
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>>> Since this driver's Qts is higher than ~0.7 though, sealed isn't a viable option since it will require an extremely large cab just to get its Qtc down to the driver's Qts.
That sucks since i have 15" woofers i wanted to use that have qts of .88 and above in sealed but the box sims out to 70+ cf... lol. Smaller, more normal sized boxes have large bass peaks that look annoying but may not sound so bad. In this instance i wonder if aperiodic would reduce the peak?
The ob speakers look cool and probably sound good too. Do you sit between them and work? can you spread them out more by moving your desk around? I would not like them right at my sides like that. But they look good!
That sucks since i have 15" woofers i wanted to use that have qts of .88 and above in sealed but the box sims out to 70+ cf... lol. Smaller, more normal sized boxes have large bass peaks that look annoying but may not sound so bad. In this instance i wonder if aperiodic would reduce the peak?
The ob speakers look cool and probably sound good too. Do you sit between them and work? can you spread them out more by moving your desk around? I would not like them right at my sides like that. But they look good!
Yes, I may try to spread them out a bit more, I just have to flip the layout of my room around. This will gain me a few feet.
I plan on suplimenting the bass, that's another project. Just deciding on a single sub, or possibly 2.(L and R)
I did need to build this bigger version to yield more of the warm midrange of these midwoofers. For the average person these would have plenty of bass.
One possibility would be to raise these up with a woofer underneath.
Anyhow here are some pics of it now.
I gave them a coat of flat black paint to seal them up a bit. I already have the butyl rubber stuck on the back, but I did paint the corners.
Then I tacked on some snappy burlap, kinda suiting for this project. We'll see how it holds up however I'm sure it will be fine. I had purchased it for another project, oh well it's dirt cheap.
Oh ya I also added a 6x8" plate abover the speakers at the back, it does improve the midd-bass projection slightly, although it sacrifices a bit of "airiness".
I still want to add some bracing, possible right on the back of the driver. There seems to be an audible result when I apply pressure there.
I plan on suplimenting the bass, that's another project. Just deciding on a single sub, or possibly 2.(L and R)
I did need to build this bigger version to yield more of the warm midrange of these midwoofers. For the average person these would have plenty of bass.
One possibility would be to raise these up with a woofer underneath.
Anyhow here are some pics of it now.
I gave them a coat of flat black paint to seal them up a bit. I already have the butyl rubber stuck on the back, but I did paint the corners.
Then I tacked on some snappy burlap, kinda suiting for this project. We'll see how it holds up however I'm sure it will be fine. I had purchased it for another project, oh well it's dirt cheap.
Oh ya I also added a 6x8" plate abover the speakers at the back, it does improve the midd-bass projection slightly, although it sacrifices a bit of "airiness".
I still want to add some bracing, possible right on the back of the driver. There seems to be an audible result when I apply pressure there.
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