Yes, someone is making comparisons between the two ( the other being M.J.King's ?)
COSTRUIRE HIFI • Leggi argomento - Scelta midwoofer per TL
COSTRUIRE HIFI • Leggi argomento - Scelta midwoofer per TL
Hmm.. My Italian sucks. What's the general consensus?
Sorry for the OT but it could be a good tool for this job.
Sorry for the OT but it could be a good tool for this job.
I'm not quite clear on what you are suggesting for the enclosure design... Are you recommending putting the woofers/LF in a bass reflex or band pass compartment, and the full ranges in a t-line? or completely dropping the t-line idea all together? Sorry if I'm missing something obvious.
It's true, I was asking about a backloaded horn a while ago. The appeal there was the db boost one gets from a horn - but it soon became clear that the cabinet would be just way too large (an issue I’m still running up against).- So I went back to the drawing board and math sheets/tables with the idea of a t-line in the hopes that a) I could get low end extension from limited drivers b) efficiency and flat response c) the challenge...
I will give the T-Line link a look, thank you for that post.
I chose the 50hz range because, from what I’ve read, that is where the “punch” is for bass. I had assumed a T-line (tapered) would be more efficient than a bass reflex, as well.
Since most of the material played through the boombox will be compressed audio to begin with (Bluetooth, FM, XM, MP3), I’m going to be fighting sound quality from the start- so my idea was to minimize anymore loss.
Wait, Pico and Thunk303, I might be getting a bit confused… are you both suggesting going sum mono but –keep the L+R speakers separated?
High SPL AND bass would be ideal- and what I thought I was going to achieve with the t-line. Solid SPL levels I guess would make up for the compressed audio. I may be coming to grips with giving up on a t-line 🙁
I will give the T-Line link a look, thank you for that post.
I chose the 50hz range because, from what I’ve read, that is where the “punch” is for bass. I had assumed a T-line (tapered) would be more efficient than a bass reflex, as well.
Since most of the material played through the boombox will be compressed audio to begin with (Bluetooth, FM, XM, MP3), I’m going to be fighting sound quality from the start- so my idea was to minimize anymore loss.
Wait, Pico and Thunk303, I might be getting a bit confused… are you both suggesting going sum mono but –keep the L+R speakers separated?
High SPL AND bass would be ideal- and what I thought I was going to achieve with the t-line. Solid SPL levels I guess would make up for the compressed audio. I may be coming to grips with giving up on a t-line 🙁
I think you may be interested in a simple bi-pole reflex enclosure with a down-firing vent. The bi-pole gets rid of baffle step loss of bass and gives SPL boost at same voltage drive level for parallel wiring. A simple 9in tall x 7.1in wide x 6in deep (all internal dims) box with a Vifa TC9FD on front and back and dual 1.7in dia x 4in ports on the bottom will give -3dB at 75Hz and 87dB down to 80Hz at 2.83v. For a boombox, 75Hz is usually enough for enjoyment of many types of music. For stereo, make two boxes side by side with chamber in between for amp (TPA3116D2) and batteries (Li-ion or SLA).
Ha ha ha
I made a TL with a 10!" woofer. Goin on since 3-4 years, I finally settled for a 3 way- 5 " midrange and 1" soft dome tw.
It plays loud and as loud you might want, but with Mp3s it sucks!
They want to be feed with a good source.
So it's an oxymoron.
And...I have no idea how a driver in (any kind of) box could sound when
driven full bandwidth ...for me it is a woofer 😕🙄
I know your mate wants to build the electronics but this is what I might use.
Yuan Jing Audio - TPA3116 Class-D 2.1 Stereo Amplifier [50W x 2]+ Sub-Woofer Board [100W] [A] - $28.60
Could run straight off a 12 or 24 V battery system 😉. Some high efficiency pro audio drivers and your rocking. 2 x 5MR450 (thanks X) and 8" in a sealed cab might even work.
I wonder if PVR has a suitable 8" to match the efficiency of the 5's?
Yuan Jing Audio - TPA3116 Class-D 2.1 Stereo Amplifier [50W x 2]+ Sub-Woofer Board [100W] [A] - $28.60
Could run straight off a 12 or 24 V battery system 😉. Some high efficiency pro audio drivers and your rocking. 2 x 5MR450 (thanks X) and 8" in a sealed cab might even work.
I wonder if PVR has a suitable 8" to match the efficiency of the 5's?
attempting to pull audiophile quality from an mp3 is definitely in the realm of Oxymoron (let alone being that 1/2 my songs are in 360kps anyway).
Thank you XRk971, I'll certainly consider that. It does seem like a more reliable/feasible option... I know 75hz would be fantastic for a portable device, but I was really hoping to pull some bass into the 50hz range (it appears Paul Carmody's Sprite is able to achieve this?). Maybe I'm just asking too much from this one project?
Thunk303: I sent my friend the link to the TPA3116 tonight and I'll go over options and ideas with him tomorrow, thank you for that.
I've come across a few DIY projects (instructables - see attached image) that involve a single dedicated sub within the boombox... but I was hoping to go another route besides bass reflex to expand my horizons. I guess the consensus is I'm just pushing a rock up a hill on this project?😱
**edit** what if I had a bipole config. for the 5" woofers and then passed the higher frequencies to the full ranges? Such as those Thunk303 proposed?
Or, and this is if I am having to truly give up on t-line, I try some band pass isobaric clamshell setup for a visually "neat" look on the low end frequencies (I plan on having the insides visible)?
I really do appreciate everyone's input and patience with me. This is a budding hobby, but one I really am enjoying sinking my teeth into.
Thank you XRk971, I'll certainly consider that. It does seem like a more reliable/feasible option... I know 75hz would be fantastic for a portable device, but I was really hoping to pull some bass into the 50hz range (it appears Paul Carmody's Sprite is able to achieve this?). Maybe I'm just asking too much from this one project?
Thunk303: I sent my friend the link to the TPA3116 tonight and I'll go over options and ideas with him tomorrow, thank you for that.
I've come across a few DIY projects (instructables - see attached image) that involve a single dedicated sub within the boombox... but I was hoping to go another route besides bass reflex to expand my horizons. I guess the consensus is I'm just pushing a rock up a hill on this project?😱
**edit** what if I had a bipole config. for the 5" woofers and then passed the higher frequencies to the full ranges? Such as those Thunk303 proposed?
Or, and this is if I am having to truly give up on t-line, I try some band pass isobaric clamshell setup for a visually "neat" look on the low end frequencies (I plan on having the insides visible)?
I really do appreciate everyone's input and patience with me. This is a budding hobby, but one I really am enjoying sinking my teeth into.
Attachments
Morning
afaiu: the more bass you squeeze from a full ranger the more the highs will suffer.
From Pauls website regarding his boombox: "The high end from a pair of 3" full-rangers is more brittle than what you'd get from a decent tweeter..."
So in my opinion it is also a question of how much sound quality you want...
Cheers
afaiu: the more bass you squeeze from a full ranger the more the highs will suffer.
From Pauls website regarding his boombox: "The high end from a pair of 3" full-rangers is more brittle than what you'd get from a decent tweeter..."
So in my opinion it is also a question of how much sound quality you want...
Cheers
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Ooh yes, you're quite into it! The thing that makes it fuzzy 🙄
is the "portable boombox" concept which involves some compromises, which are seen as big limitations by the...diligent & wise listener.
So you may do anything you want, bearing in mind that putting in a room two distinct sound sources -loudspeakers- is different that bringing anywhere a "box containing 2-3 loudspeakers". I'm referring to your observation about declaring about a box having F3=55 Hz in ambient, see room gain...
I myself built several TL boxes, or recalling something similar to a TL 🙄
possibly 3 way
But just for fun - for the fun to have them playing for some time in my room...while studying the rest of the system
The real BIG ONE that'll destroy the good ol' ones is yet/next to come
is the "portable boombox" concept which involves some compromises, which are seen as big limitations by the...diligent & wise listener.
So you may do anything you want, bearing in mind that putting in a room two distinct sound sources -loudspeakers- is different that bringing anywhere a "box containing 2-3 loudspeakers". I'm referring to your observation about declaring about a box having F3=55 Hz in ambient, see room gain...
I myself built several TL boxes, or recalling something similar to a TL 🙄
possibly 3 way
But just for fun - for the fun to have them playing for some time in my room...while studying the rest of the system
The real BIG ONE that'll destroy the good ol' ones is yet/next to come
Sayrum:
the ultimate goal is to reproduce the best sound quality I can (esp. given that the formats played will be lossy to begin with)... which is where I happened on the idea of a t-line. The initial mockup was to cross the fullranges at 350hz or so to mediate that brittle nature of a full range :/ Any suggestions or if that is an appropriate point?
https://www.parts-express.com/pedocs/specs/296-717-fountek-fe85-specifications.PDF
the ultimate goal is to reproduce the best sound quality I can (esp. given that the formats played will be lossy to begin with)... which is where I happened on the idea of a t-line. The initial mockup was to cross the fullranges at 350hz or so to mediate that brittle nature of a full range :/ Any suggestions or if that is an appropriate point?
https://www.parts-express.com/pedocs/specs/296-717-fountek-fe85-specifications.PDF
Pico:
Hahaha! I'm just getting my feet wet and I'm also thinking about the "next to come.." - I foresee this as a never ending "problem"😉
did you ever test your T-Lines in other environments to see how it effect sound reproduction? Are they very limited to the room they are designed for?
the "boombox" concept is giving me fits, since I know several of the locations It'll be played in are a large barn/workshop, outdoor picnic (no walls for gain), inside my various rooms in the house, and at or near a wall on our boat... all are drastically different 😱
Hahaha! I'm just getting my feet wet and I'm also thinking about the "next to come.." - I foresee this as a never ending "problem"😉
did you ever test your T-Lines in other environments to see how it effect sound reproduction? Are they very limited to the room they are designed for?
the "boombox" concept is giving me fits, since I know several of the locations It'll be played in are a large barn/workshop, outdoor picnic (no walls for gain), inside my various rooms in the house, and at or near a wall on our boat... all are drastically different 😱
The secret of a fullrange is the glue that holds the dustcap !!
That is called mechanical break up, when there's loose of energy
On the other side- from micro to macro- the behavior of the speaker in a box
is different and room gain applies to it either. Of course the FF 85 in a box won't sound as loud as a, say, 4", and that its diameter suggests a similar sound wavelenght like > 500 Hz and power together with excursion in the bass band when required by the program playing, so it brings to the phisical execution of the driver...well 20 mm VC diameter and 12 W rms
...
That is called mechanical break up, when there's loose of energy
On the other side- from micro to macro- the behavior of the speaker in a box
is different and room gain applies to it either. Of course the FF 85 in a box won't sound as loud as a, say, 4", and that its diameter suggests a similar sound wavelenght like > 500 Hz and power together with excursion in the bass band when required by the program playing, so it brings to the phisical execution of the driver...well 20 mm VC diameter and 12 W rms
...
The recommendation I was trying to make was to mono the bass, and use any enclosure you like. If you want to use a transmission line, then go for it. You should imememt a single enclosure for low frequencies, and thus have "double" the volume to work with compared to trying stereo bass.
The enclosures for the "highs" can be very small indeed, which will make placement easier. I really think the xo can be much higher than you would normally use for a sub, as the box is "fixed" and the left and right speakers quite close to the low speaker.
If you do this with an electronic xo you will be able to tweak the xo very simply. Additionally, you get a significant spl benefit in using an active xo and three amplifiers.
The enclosures for the "highs" can be very small indeed, which will make placement easier. I really think the xo can be much higher than you would normally use for a sub, as the box is "fixed" and the left and right speakers quite close to the low speaker.
If you do this with an electronic xo you will be able to tweak the xo very simply. Additionally, you get a significant spl benefit in using an active xo and three amplifiers.
The*best* would be to make everything compact ( as at home ) and separated, I mean, heavy duty !
Also see the car audio ( but it conflicts with portability, as there's no engine recharging the batteries) or PC-advanced multimedia systems : the subwoofer carries the power/*bump*
effect and is often double/triple than the...satellites.
The subwoofer is a separate unit which can be setted for optimization by the means of phase/level/Fcut/boost and can be hidden.
I've got to build for a 4"/10 W woofer a huge TL, replica of one of mines from a 3 way and having a 6.5" woofer. It will be driven by a 3W BTL chip amp, the same you find in the very cheap 2.1 sets ( it works good )
The fact is that I don't want to put a big box anymore in my room, and I don't need a 3 W- cheap-stupid -sub-woofer !!
Also see the car audio ( but it conflicts with portability, as there's no engine recharging the batteries) or PC-advanced multimedia systems : the subwoofer carries the power/*bump*
effect and is often double/triple than the...satellites.
The subwoofer is a separate unit which can be setted for optimization by the means of phase/level/Fcut/boost and can be hidden.
I've got to build for a 4"/10 W woofer a huge TL, replica of one of mines from a 3 way and having a 6.5" woofer. It will be driven by a 3W BTL chip amp, the same you find in the very cheap 2.1 sets ( it works good )
The fact is that I don't want to put a big box anymore in my room, and I don't need a 3 W- cheap-stupid -sub-woofer !!
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Hey iFearFractals
an easy build with a proven sound quality would be the Overnight Sensations.
Tuned to 53Hz 😀
They come with ready made cabinets (afaiu). You just use them and get some stereo imaging by placing the two cabs seperatly or ask parts express to buy without the cabs. Or make a quick "disconnect" between the cabs, "click" together for transport and seperate for better sound quality...
Only drawback i see is the mediocre sensitivity: 83 dB 1W/1m -> they need more power from the amp.
Regards
an easy build with a proven sound quality would be the Overnight Sensations.
Tuned to 53Hz 😀
They come with ready made cabinets (afaiu). You just use them and get some stereo imaging by placing the two cabs seperatly or ask parts express to buy without the cabs. Or make a quick "disconnect" between the cabs, "click" together for transport and seperate for better sound quality...
Only drawback i see is the mediocre sensitivity: 83 dB 1W/1m -> they need more power from the amp.
Regards
Saryum: I actually just finished constructing a pair of the OS for my parents home theater (I customized them for sattalite use and to their visual standards - blending with the physical background). That was a really fun and enlightening project 😀 - I'll give this configuration some thought, good idea.
googlyone:
I think i'm getting a better understanding of what you are suggesting... but correct me if I'm wrong : for the "bass" speakers are you saying to sum the signal in mono -> feed that through an amp -> to the speakers which I wire in parallel? Currently, that would give me an impedance of 4ohm, while the full ranges are still 8ohm... since there will be sepperate amps does this matter?
googlyone:
I think i'm getting a better understanding of what you are suggesting... but correct me if I'm wrong : for the "bass" speakers are you saying to sum the signal in mono -> feed that through an amp -> to the speakers which I wire in parallel? Currently, that would give me an impedance of 4ohm, while the full ranges are still 8ohm... since there will be sepperate amps does this matter?
Pico:
do you have a link to the 3W chip amp you own? Did you purchase that or scavenge it from another devise? for my purpose of a portable all in one box, would this be something i should take a look at or consider?
do you have a link to the 3W chip amp you own? Did you purchase that or scavenge it from another devise? for my purpose of a portable all in one box, would this be something i should take a look at or consider?
I've never used the program SketchUp before, so I thought I'd take the opportunity to do so: Here are some mock-up modeling and post what I have **if** I modeled as a t-line...
* I still haven't had a chance to go over MJK's MathCad program, but I was bored in lab today, so here' my result
* I still haven't had a chance to go over MJK's MathCad program, but I was bored in lab today, so here' my result
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You should probably investigate negative taper (narrowing) transmission lines as you play with the MatchCad spreadsheets. This alignment should deepen the bass response somewhat (at the cost of efficiency, which is not a prime goal for this project, anyway)
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