Mick35 Posted March 9, 2012 Posted March 9, 2012 I think I have given up on it to be honest... went and bought a pair of shl5 instead... Harbeth? NICE!!
kye Posted March 10, 2012 Author Posted March 10, 2012 evening gents... I get back from a week abroad and find much action has occurred! mick: no joke - i'm not that cruel! seriously though i'm disappointed that you're not happier with them. there are likely several things going on here. first up would be that i'm not a tone meister, and I listen to music for expression and not tone. these drivers are more aligned with how PA drivers are made, and they have the same feel to me - big, detailed, expressive but in no way smooth. i've been playing with the crossover and the tone is much better now, i'll post it up when i've got it scanned and uploaded. second is the room. mine is small (3.5 x 3m - ish). placement is perhaps 50cm from the rear wall (ie, drivers >1m from rear wall). as I said previously the bass isn't deep or loud, but what is there is fast and articulate (and adequate on most acoustic materials IMHO) third is vintage - my drivers were purchased over a decade ago. I compared them with the new stock and they seemed the same, but maybe i'm missing something here. fourth is break in - mine are well broken in and I know that timing wise, drivers need a good amount of breakin fifth is warmup, although i'm not confident i've heard this. the theory sounds plasible, but who knows. the eigth is cost, which in this case is pretty darned low. I suspect you may be using the first version of the crossover? that was *ahem* very lean...
kye Posted March 10, 2012 Author Posted March 10, 2012 measurements will be a problem - I haven't got the equipment to do so anymore. I have a mic and appropriate computers, but lack a device that has phantom power for the mic. I must admit they're improved with a tweeter and subwoofer, but *need* is a strong word for such things. it does depend on what music you're listening to. I could happily get by listening to most music on these without tweeters or woofers. i'm most of the way through a second build for a good friend of mine - I think they'll end up with three drivers per side instead of four. these will have brand new drivers in them and i'll see if there's much difference.
kye Posted March 10, 2012 Author Posted March 10, 2012 righto - here's the current crossover: the drivers are (from left to right): RAAL tweeter, top 8", second top 8", remaining two 8" drivers mick, perhaps this will round your sound out a bit? whatever you do, don't put in a notch filter - I have gone down this road and you erase the magic from these drivers, leaving you with their other (less than stellar) attributes. these drivers are great because they have the magic, not because they're great drivers in any traditional sense.
Mick35 Posted March 10, 2012 Posted March 10, 2012 Hi Kye, Hope you had a great time abroad? You'll be pleased to know that my initial thoughts ('Complete Rubbish') have changed somewhat, to ('These things have got some potential') especially the more I listen, and swap my front end around. With regards to crossover, are you know running the coil on the bottom three drivers. and leaving the top one to run 'Full range'? I was thinking of doing that today actually, but as I had to build my other channel, Time beat me, so I wired up as per 1st schematic, although on the second channel, I used a bigger cap on my tweet 2uf and a bigger coil (Forgot) on the bottom two drivers, this smoothed out the sound better in my room, and I liked it more than the first channel. Better detail and decay on things like, light cymbal strikes, brushes, and higher piano chords, as well as more refined strings on various instruments. You know all that 'Jazzy trio stuff'? I'm like you, I like to listen to music, not 'Pink Noise', but if I can get my hands back on my Mic pre, then a few measurements might be a necessary evil oneday? Until then though, very much enjoying the experimenting and listening. Certainly more to come from me as well.
kye Posted March 10, 2012 Author Posted March 10, 2012 Hi Kye,Hope you had a great time abroad? You'll be pleased to know that my initial thoughts ('Complete Rubbish') have changed somewhat, to ('These things have got some potential') especially the more I listen, and swap my front end around. With regards to crossover, are you know running the coil on the bottom three drivers. and leaving the top one to run 'Full range'? I was thinking of doing that today actually, but as I had to build my other channel, Time beat me, so I wired up as per 1st schematic, although on the second channel, I used a bigger cap on my tweet 2uf and a bigger coil (Forgot) on the bottom two drivers, this smoothed out the sound better in my room, and I liked it more than the first channel. Better detail and decay on things like, light cymbal strikes, brushes, and higher piano chords, as well as more refined strings on various instruments. You know all that 'Jazzy trio stuff'? I'm like you, I like to listen to music, not 'Pink Noise', but if I can get my hands back on my Mic pre, then a few measurements might be a necessary evil oneday? Until then though, very much enjoying the experimenting and listening. Certainly more to come from me as well. the week in singapore was very nice - thanks good to hear the culprit is likely the crossover, it's something that's pretty easy to fix! you're correct that the top driver is being run fullrange, with the rest being filtered. i'm not sure, but I suspect with the crossover i've made that the bottom two are filtered differently to the second one, but perhaps i'm wrong in this regard. i tuned it by ear and it sounds pretty good to me, however you may be able to make progress and i'm happy to take advice on tonal balance as it's not my primary focus. interesting that you suggest your front end as a variable. have you got access to any analogue sources? bad digital is horrible and these speakers will reveal it ruthlessly, so it would be great to get an analogue opinion. I don't have an analogue front end so can't comment. measurements aren't a necissary evil, I have done many many measurements over the years tuning crossovers and testing other various things. I found them to be good at getting in the ballpark, but inadequate at making progress since then. if you have another pair of speakers you can compare these to, then you can swap back and forth using the others as a reference of sorts. this should get you into the right kind of territory for tonal balance. i've done this with headphones and it's not a bad approach. even better is when you use a wide range of test music and get a sense of what the overall balance is on instruments and vocal intonations are with different singers. as these are fullrange drivers it's a different kind of process, more like tonal shaping than tuning, but the end goal is basically the same.
kye Posted March 10, 2012 Author Posted March 10, 2012 I think I have given up on it to be honest... went and bought a pair of shl5 instead... hi RLDK, a very functional looking build you've constructed - scarily similar to mine! extra tweeters would be required if you're looking for the complete 20-20k experience as many are, the vifa ring radiator tweeters are quite good for the money. if you're interested in pursuing the project (and not letting the cabinetry go to waste!) then happy to help out with crossover tweaks etc.. I suspect you've gone with the early crossover version?
Mick35 Posted March 10, 2012 Posted March 10, 2012 Hi Kye, Front end isn't variable as such. Just been trying a few different amp, digitall source combos. I too lack an analog source, would be nice to hear what the speakers sound like with just an analog source. Righto, I'm off to Jaycar this morning, for some bits and bobs. If I get time today I'll post some pics of my setup. Thanks again Kye for sharing your crossover progress, we are both thinking along the same lines. Keep it 1st order, and keep it simple.
RLDK Posted March 11, 2012 Posted March 11, 2012 hi RLDK, a very functional looking build you've constructed - scarily similar to mine! extra tweeters would be required if you're looking for the complete 20-20k experience as many are, the vifa ring radiator tweeters are quite good for the money. if you're interested in pursuing the project (and not letting the cabinetry go to waste!) then happy to help out with crossover tweaks etc.. I suspect you've gone with the early crossover version? Hey kye, I've got mine currently all running full range, no x-overs. Its hooked up to the TV's built in amp so I'm just listening to TV on it. If you r up for the gtg, I wouldnt mind having a listen and see what the potentials are like here. Would really know what it can do before I spend more time n money on it tbh.
kye Posted March 12, 2012 Author Posted March 12, 2012 Hey kye, I've got mine currently all running full range, no x-overs. Its hooked up to the TV's built in amp so I'm just listening to TV on it.If you r up for the gtg, I wouldnt mind having a listen and see what the potentials are like here. Would really know what it can do before I spend more time n money on it tbh. these drivers aren't great when run fullrange, so that will be the cause of your initial dismay! they really need the crossover to balance them up tonally.. I was going to suggest that you're most of the way there, but then looked up how much 1.8mH inductors are and got a nasty surprise - wow! that's one overpriced product (a few metres of wire on a plastic bobbin..) will see how I go with the gtg. i'll have to convince the head of the household to let people i've never met into our house - never an easy thing B)
Mick35 Posted March 12, 2012 Posted March 12, 2012 Well.........It had to be done, even if it was just to satisfy my own curiosity. I hope you don't mind Kye? What did I do? I moved the inductor up so it filters All 4 Drivers, as for the size of the coil a 0.33mH is what I used. For the tweet I stepped the cap up to a 4.7uF, this makes a 1st order cross around 4khz. Why? My listening room is very 'Lively', hard floors, and walls and ceiling, and very little furniture (I'm working on it though LOL!) These drivers have a rising response, starting around 2.5khz, and climbing about 10db, to about 7khz, then rolling off. My hearing is quite sensitive in this range, and it was driving me NUTS!! in my lively room. The result, much much smoother to listen to, Quite the 'Toe Tapper' these things are, hard to believe you'd get change for $250, the 'Magic' is still there (In my Room). If your room was treated, then I can see that the extra energy would dissipate quite quickly, leaving the speakers sounding flat and lifeless. Also now that I've got both channels going, I can listen to how they stage and image, I'm still getting the position right though, as I listen quite close, and with the ribbon tweets, the correct 'Toe in' is important, so just playing with distance apart, toe in and listening position, but as an initial observation, I really like what these things stage and image like. For an 'Open Box' design, image is nice and tight, not pinpoint mind you, but not as diffuse as my fully open baffled speakers. Soundstage is good, not as wide, tall or deep as my dipoles, but this may change as I sort my positions out better, all in all, I'm rather pleased at this point. I'll listen for the next week tweaking the positions of speakers and listening distance, and see what I discover. I've also got a pair of cheap eminence Alpha's, lying Idle from another project, and they just so happen to be the right sensitivity as the rest of the system. Might whack them in a pair of 'H' frames, drop a big coil on them and see if I can get a bit more bottom end thump out of these babies? The weekend is spoken for already LOL!!
kye Posted March 13, 2012 Author Posted March 13, 2012 many people call drivers like this 'fullrange' which obviously they are not, so to really be fullrange they require augmentation at both ends. this leaves them in the position of being wideband mids, which is a very good overall topology IMHO - when done right you get almost all the benefits of a single driver, but also an extended response. as you rightly point out mick, the question is whether to filter them or not, and that's especially relevant when they've got a rising response (as these indeed do). I think regardless, these drivers are quite good midranges, and when you consider the price, they are stunningly good value. I have tried various topologies even before the first version I published here, and came to the conclusion that significant magic was lost when they are filtered, despite them becoming better tonally. even if you continue to use them as wideband mids with filtering, I think you'll still get much enjoyment from them, and the effort of building a speaker around them is still well worth it. however once you've gotten a nice 3-way setup going and you've gotten used to the sound, I would encourage you to try the "one fullrange and others filtered" approach again (moving the tweeter crossover up so it only cuts in above the natural rolloff of the driver running fullrange) and see if you can get more of the magic with that setup. as far as woofers for these things, i've spent considerable time matching a sub to these things (see my thread about getting 20Hz bass) and found that I couldn't do it with passive crossovers - they didn't filter out enough and I was left with too much boom in the bass and upper bass ranges. i've now got an active crossover and have settled on a 64dB/octave (yes, 8th order!) low pass at 37Hz. I made a test track that had sine waves on it that were each musical note (ie, playing a scale) and this setup provides a basically flat response in my room. see how you go though! the imaging won't be pin-point, but there are things you can do to help. mainly, imaging is about baffle width and corner diffraction, so get these in control and you'll be on the right track. obviously you can't make the baffles narrower than the drivers, so these won't out-image an array of 4" mids (or the arrays of 1" drivers I have built previously) but you should get OK results. I have a lot of opinions about imaging (I think I expressed some of them earlier in this thread) but basically ambience is musically relevant, and precision (pin-point) isn't musically relevant. next time you're passing a busker in the street stop and listen and think about imaging - it's an eye opening excercise!
Paul Spencer Posted March 13, 2012 Posted March 13, 2012 kye, Some of the answer would be found in off axis measurements. While this driver and many like it have a rising top end on axis, this changes off axis. Altering toe in provides a kind of acoustic EQ, especially where it is beaming. This is where it becomes a little more complicated, and where looking purely at the axial response gives an inadequate picture. Making it a dipole also adds a bit more complexity because you have lateral nulls, which by toe in you can aim at first reflection points. With deep wings that changes things a little. I suspect you may get better results with very shallow wings (or hinged wings angled), then bringing in a woofer which can make the wings smaller or not needed.
kye Posted March 13, 2012 Author Posted March 13, 2012 hi paul - the answer to what question / problem? sorry I didn't follow the context you're right about the on and off axis behaviour. I am a fan of widening the range of the mid driver to get the most coherent sound, which while in this case isn't a single driver, it's multiple of the same driver, which is still an advantage. the next pair i'm working on for a friend have the opening at the bottom of the rear baffle, so the front-to-back distance can still be substantial whilst not needing to be very deep. obviously this will be subject to internal cabinet reflections and have less OB goodness, but it would allow cabinets to be almost(?) 10cm deep!
Mick35 Posted March 13, 2012 Posted March 13, 2012 Evening Chaps, OK just tried a giant whack of copper coil, and your right Kye, the roll off is just far too shallow. Too much higher energy getting past, so that counts out the simplicity of a 1st order. Have you tried a fouth order passive Kye? I've priced it out and materials and with my discount and what I already have on hand that will work come out to about $90, average quality parts mind you, For me that's doable, for a weekend 'Let's learn something' Day. Thinking 15inch drivers in 'H' frames with a singe Alpha each side, just to keep it open baffle at this stage. My room is large, about 35m2, so looking to cross around 130hz at this stage. I've gotta give something a go, bass is there, but in my space it's weak and uninvolving. What is there though is precise and articulate.
Paul Spencer Posted March 13, 2012 Posted March 13, 2012 Kye the problem being one of the rising top end response (on axis)
Art Vandelay Posted March 13, 2012 Posted March 13, 2012 (edited) Infinity Renaissance 90 - with RAAL 140-15 tweeters. Crossover from EMIM to RAAL is 4th order passive L-R. The tweeter crossover uses copper foil inductors and SIO Mundorf caps. The EMIM crossover has been redesigned to achieve a flat response on axis (wth toe in). All MB and Woofer caps and inductors have been upgraded (of course). The DIY PA is at the bottom of the cabinet. Not pure DIY and perhaps not the world's best but very very good. Edited March 13, 2012 by Art Vandelay
Antripodean Posted March 13, 2012 Posted March 13, 2012 I will suggest this as a line array that would perform very well, complete with measurements - the CBT36 designed by Don Keele
ALF- Posted March 13, 2012 Posted March 13, 2012 Here!!!!! WHAT'S MY WIFE'S CUP DOING ON YOUR COFFEE TABLE?!? ;)ALF Hey Mick, I actually built a pair too and have the same conclusion as you. Tweeter is definitely required with these speakers. Comparing these with the fostex, the clarity n fizz is lacking in the top end. I've got mine crossed fairly high and the bass is definitely there, but there are spikes in the midbass where a particular note would boom. It might be the way it is positioned currently, loading up against a rear wall. will try different positions later on. Not having spare pair of tweeters, I was thinking of using a fairly affordable VIFA XT25 ring radiators. What do you think?
kye Posted March 14, 2012 Author Posted March 14, 2012 mick - i'm not too optimistic about passive fourth order.. $90 is a fair whack if it's the wrong frequency - you'd have to buy a lot more components to adjust it up and down and fine-tune it! this is really where active crossovers come into their own, unless you are up for building a passive line-level crossover (and have a spare amp to run them)? I am happy to help you work out values if you go down that route.
kye Posted March 14, 2012 Author Posted March 14, 2012 the bass response was one element of line arrays that I never quite figured out - are you saying that the rising response of a driver is evened out when it's put into a line array? these drivers could be an excellent candidate for a line array - cheap and readily available! if active woofers were used, the depth could be reduced... towers only 30-40cm deep and 20cm wide would be on the more acceptible side, and they'd be very efficient!
Mick35 Posted March 19, 2012 Posted March 19, 2012 Just another update from me. I managed to build a pair of 'H' frames for a pair of eminence Alpha 15a's. Building these was easy enough, and as I was building and thinking about the crossover, I decided to, just for fun, try a 1st order cross at 100hz. Originally I thought about 130, but with a steeper slope. I didn't have all the parts for a steep slope, but I had some parts for a 1st order, but for a 100hz cross, I was going to need some serious amounts of copper coil. Managed to get some large inductors from jcar, and with the bass frames built, it was time for a test on the cross. At 100hz a complete failure, far to much mid bass, and it was drowing out my nice smooth top end, that I was enjoying. Add more copper! LOL! 70hz this time, much better, but after a little listening, still not right. Lucky for me the third time 'Was a charm' and at 40hz first order in my room, all is good. All up about 27mh of inductance. Yep! about 3kg of copper on each speaker resides behind the bass units. With the extra bass, these speakers sound very very good indeed. I know I can tweak further, and I will, but I'm happy right about now. These speakers are just so easy to listen to. They are lightening fast, ribbon tweets work very well, domes may struggle. They are nimble and very detailed, but not shrill or piercing at all, very smooth. They play very loud and very clean. I was sitting there by myself, and I wound the wick right up Twice what I'd normally go, and just simply enjoyed track after track. It was then I heard a noise, got up and it was someone at the door. It wasn't until I tried to speak, that I realised just how loud and clean these things were playing. I didn't even notice. FANTASTIC STUFF!! 1 1
millsy Posted March 19, 2012 Posted March 19, 2012 Just another update from me. I managed to build a pair of 'H' frames for a pair of eminence Alpha 15a's. Building these was easy enough, and as I was building and thinking about the crossover, I decided to, just for fun, try a 1st order cross at 100hz. Originally I thought about 130, but with a steeper slope. I didn't have all the parts for a steep slope, but I had some parts for a 1st order, but for a 100hz cross, I was going to need some serious amounts of copper coil. Managed to get some large inductors from jcar, and with the bass frames built, it was time for a test on the cross. At 100hz a complete failure, far to much mid bass, and it was drowing out my nice smooth top end, that I was enjoying. Add more copper! LOL! 70hz this time, much better, but after a little listening, still not right. Lucky for me the third time 'Was a charm' and at 40hz first order in my room, all is good. All up about 27mh of inductance. Yep! about 3kg of copper on each speaker resides behind the bass units. With the extra bass, these speakers sound very very good indeed. I know I can tweak further, and I will, but I'm happy right about now. These speakers are just so easy to listen to. They are lightening fast, ribbon tweets work very well, domes may struggle. They are nimble and very detailed, but not shrill or piercing at all, very smooth. They play very loud and very clean. I was sitting there by myself, and I wound the wick right up Twice what I'd normally go, and just simply enjoyed track after track. It was then I heard a noise, got up and it was someone at the door. It wasn't until I tried to speak, that I realised just how loud and clean these things were playing. I didn't even notice. FANTASTIC STUFF!! You've come a long way from your original thoughts! Thanks for posting up your progress and not giving up at the beginning!
Mick35 Posted March 19, 2012 Posted March 19, 2012 Thought I'd better post a pic of my efforts LOL!! 1 1
Mick35 Posted March 19, 2012 Posted March 19, 2012 You've come a long way from your original thoughts! Thanks for posting up your progress and not giving up at the beginning! Yes that's true. Kye's right though, and I'm just learning this myself, and that is these drivers are on a knife edge, too far either way and you lose the 'Magic', tweak and fiddle to get it right, however, and you can be rewarded, with some great sound. 1
Recommended Posts