Hi all,
I'm a relative noob to home audio, having spent 13 years in car audio I'm about to start piecing together my 1st home system. I'm building my own speakers (3 or 4 way floor standers, 2x 8" Dyns, 1x 6.5" Focal Utopia and Dali Ikon ribbon and tweets per side) and subwoofer (4ohm final load, B139 x2) and need to think about amplification.
I have a HD TV with HDMI outputs, so would like to be able to link that in, as well as a PS3 which I'll probably use as my CD source.
Now I can get a stereo signal out of the TV or PS3, so HDMI isn't vital, neither is 5.1/7.1-I'll only ever watch the odd movie and am not bothered about suround sound music at this juncture-though it may be useful for the future-the main reason for wanting HDMI in and out is easy of connection.
So 2.1 is the minimum requirement-however I would like to know if anyone is aware of any multi-channel amplifiers that will accept multiple inputs or give multiple filtered outputs-I'm considering going active with my set up (very common in car audio and loads of choice of equipment) but after scouring ebay (told you I was tight) I've not come up with anything that looks like it will do as I wish.
SO, what do you know? What should I be looking at? I have found a bunch of stereo Pioneer amps on ebay that are very cheap, so could just get 4-5 of them-but then space and her in doors both become issues.
Are the little amp kits on ebay any good? Sound quality and power wise?
Good amps to look out for? Bad amps to avoid? Any guidance much appreciated, not loking to blow the roof off, but would have though 80wrms PC at least?
I'm a relative noob to home audio, having spent 13 years in car audio I'm about to start piecing together my 1st home system. I'm building my own speakers (3 or 4 way floor standers, 2x 8" Dyns, 1x 6.5" Focal Utopia and Dali Ikon ribbon and tweets per side) and subwoofer (4ohm final load, B139 x2) and need to think about amplification.
I have a HD TV with HDMI outputs, so would like to be able to link that in, as well as a PS3 which I'll probably use as my CD source.
Now I can get a stereo signal out of the TV or PS3, so HDMI isn't vital, neither is 5.1/7.1-I'll only ever watch the odd movie and am not bothered about suround sound music at this juncture-though it may be useful for the future-the main reason for wanting HDMI in and out is easy of connection.
So 2.1 is the minimum requirement-however I would like to know if anyone is aware of any multi-channel amplifiers that will accept multiple inputs or give multiple filtered outputs-I'm considering going active with my set up (very common in car audio and loads of choice of equipment) but after scouring ebay (told you I was tight) I've not come up with anything that looks like it will do as I wish.
SO, what do you know? What should I be looking at? I have found a bunch of stereo Pioneer amps on ebay that are very cheap, so could just get 4-5 of them-but then space and her in doors both become issues.
Are the little amp kits on ebay any good? Sound quality and power wise?
Good amps to look out for? Bad amps to avoid? Any guidance much appreciated, not loking to blow the roof off, but would have though 80wrms PC at least?
Hi,
One thing for sure is domestic speaker design is far more more complicated
and elaborate than the way you do car stuff, if you want genuine hifi results.
You can't buy domestic multichannel amplifiers with various active filter
setting for bass, mid bass, mid and treble like you can in the car world
because they simply don't work properly with real drivers in real boxes.
rgds, sreten.
One thing for sure is domestic speaker design is far more more complicated
and elaborate than the way you do car stuff, if you want genuine hifi results.
You can't buy domestic multichannel amplifiers with various active filter
setting for bass, mid bass, mid and treble like you can in the car world
because they simply don't work properly with real drivers in real boxes.
rgds, sreten.
lol-you've obviously not heard some of the cars I have-a much harder environment to get to sound good and these have genuinely knocked spots off the best home systems I have heard. Not that I've spend much time listening to great home systems admitedly. Probably the best I've heard was a B+W 6series system, was ok but not in the same realms as car audio systems I've heard for the same money or less-a lot of work goes into a car system-mine has around 40hrs in it on install alone-quite a lot for 5 speakers, a stereo and 4 amps in a 2003 Mini...careful research saw me do LT with no separate EQ needed and a 0.126cf enclosure for a near perfect flat response with 0 tuning.
Home is defo an easier environment, by considerable margins, I agree it's not simple but it's a lot easier than getting a comparible sound in a vehicle.
So, if we rule out 7 active channels what are your recommendations on a good "budget" amp or a good 2nd hand choice?
Home is defo an easier environment, by considerable margins, I agree it's not simple but it's a lot easier than getting a comparible sound in a vehicle.
So, if we rule out 7 active channels what are your recommendations on a good "budget" amp or a good 2nd hand choice?
I would try your sub setup used for the car in the house with your home amp
and measure the SPL for flatness up to 100 hz.
If you have a power supply for the car amp you can use that as the response is known in the car.
if you can get flat bass to 100Hz in the house , you have the basis of a great system as many bookshelf speakers can be used to complement the sub.
and measure the SPL for flatness up to 100 hz.
If you have a power supply for the car amp you can use that as the response is known in the car.
if you can get flat bass to 100Hz in the house , you have the basis of a great system as many bookshelf speakers can be used to complement the sub.
To resonate the vehicle's panels with a single tone bass is not high fidelity. I guess it depends also whether you listen to Jazz at the Pawnshop or Dr Dre.
A KEF B139s is not the driver of choice to do VOOOOOM VOOOOM. Furthermore, the driver choice, cabinet design and cross-over goes hand in hand.
A KEF B139s is not the driver of choice to do VOOOOOM VOOOOM. Furthermore, the driver choice, cabinet design and cross-over goes hand in hand.
Building stuff yourself might not be the best option if trying to do it on the cheap, but will certainly give you the custom fit your after.
Something that might be of intrest to you is MiniDSP. Worth a look see if your thinking about active X-over, EQ etc...
Best route i can think of as a starting point is with an intergrated stereo amp, bookshelf speakers [with weighty stands] & sub. You could use the minidsp 2.1 between the tv/ps3 stereo outputs and amp. This would give you an tunable high pass/low pass filter and EQ. Or you could get an active sub fitted with a high pass filter and spend some time/money tuning the room [furniture & audio panels].
Best of luck...
Something that might be of intrest to you is MiniDSP. Worth a look see if your thinking about active X-over, EQ etc...
Best route i can think of as a starting point is with an intergrated stereo amp, bookshelf speakers [with weighty stands] & sub. You could use the minidsp 2.1 between the tv/ps3 stereo outputs and amp. This would give you an tunable high pass/low pass filter and EQ. Or you could get an active sub fitted with a high pass filter and spend some time/money tuning the room [furniture & audio panels].
Best of luck...
Hi,
I stand by what I said. The only thing easy about home speakers is getting
it wrong due to one, or many more, details you not aware of or have chosen
to ignore, or misunderstand in the first place. The home environment is far
more critical of replay system faults than in-car systems, by a long way.
(In the same way a decent loud AV system can be poor with subtle music).
Any arrogance will come back to bite you severely, (or not, some
assume they've built the speakers right, so therefore they are right).
For 3 ways i'd go active mid/bass and passive mid treble, 2 stereo amps.
Quite a few amplifiers have a matching power amplifier, for bi-amping.
See : Hybrid Design
Depending on the Dynaudio bass drivers the B139's may bring little
to the party, restricted Xmax of the B139's makes them ideal as
subs for small inefficient speakers, not high Xmax 2x8" bass.
Used amplifiers are only as good as what you pay for them. Popular
stuff is pricey, less popular or not so well known can be bargains.
rgds, sreten.
http://sites.google.com/site/undefinition/diy (see if nothing else, the excellent FAQs)
The Speaker Building Bible
Zaph|Audio
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
http://audio.claub.net/Simple Loudspeaker Design ver2.pdf
FRD Consortium tools guide
Designing Crossovers with Software Only
RJB Audio Projects
Jay's DIY Loudspeaker Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
A Speaker project
DIY Loudspeaker Projects Troels Gravesen
Humble Homemade Hifi
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design
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No, really, I thought SQ was a 20 year old Corsa with two 15” in the boot. Believe it or not, some of us car audio nuts do have brains, know what a good system sounds like and don't go round trying to wake the dead.
In my CAR CD player right now? Focal Spirit of Sound Demo disc....
Though as it’s not bigoted it’ll happily play Dre, Rebecca Pigeon, Skrillex, Prodigy, Curtis Mayfield, Led Zep, Hendrix-anything I throw at itThanks for the link-I am aware of the Mini DSP and it is a potential option-though the lack of multi-channel amps in the home market looks like it may make it a costly choice with the required channels of amplification.
Room treatments will be out-I’m already obsessive enough with my car audio and another obsession won’t wash well with the Missus.
Not at all, I realise that this isn’t a simple process, I just don’t think most HA guys have much appreciation car audio and what is involved in building systems from raw drivers in an environment that has so many intrinsic problems. You need to do everything you’d have to for a home speaker and then consider the off centre seating position, instrument panels, transmission tunnels, different crossover slopes and points for LHS drivers compared to the RHS drivers…
It would never work in the house, not designed to. The Mini it is fitted in has huge cabin gain, so the enclosure was built to work with that-not my living room. Out of car the F3 of the current enclosure is 76.84Hz, just to get it to 45Hz I’d have to make the enclosure 5x bigger and port it…
Trust me, I’m not going into this blind, I realise I still have lots to learn, I wasn’t wishing to appear arrogant, as said above I think people, in general, make the mistake of thinking car audio is all boom-boom-tsss.
While most of the market fall into the 17-25yr old demographic who wouldn’t know what phase was I don’t fall into that category-I recently had a customer who sells home audio (has done all his career) who was more than pleasantly surprised at my knowledge, just because I don’t know what’s available in the home market it doesn’t mean I don’t have a good understanding of the principles employed or the ability to learn new ones. As said I spent around 40Hrs installing my modest car system-but months and months of research and planning went into it, achieving the response I did with 0 EQ work isn’t easy.
The B139 are there for reinforcement, mainly for movies, and will be powered by a separate amp/channel whatever route I take with the floor standers so can be matched in output with the Dyns.
Thank you for the links, I’ve read a few of them before, but a refresh never goes amiss, the new ones will give me something to do now it’s raining again!
Images below are my B139's predicted response. EDIT wrong RTA, deleted while I find the right one!
So, if anyone other than BuildMeSomething and Sreten have anything useful to contribute please do
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I just got a reply about one of these: Yamaha DSP-AX750SE that I q'd a guy on ebay about-claims it will do 3 x stereo pairs and sub, no filtering. Would leave me doing the dyns off one pair, Focals off another and the Dali units on the final pair-any thoughts on these?
Unfortunately have now missed the sale but could keep an eye out for another if suitable.
Unfortunately have now missed the sale but could keep an eye out for another if suitable.
The B139 is typically rated at 50 watt, it has a limited excursion therefor it would not shake the walls. However, it can go low - very low and in an isobaric loaded transmission line, it would be flat down to 17 Hz.
Personally I would not use B139 as subs since they are quite capable of frequencies up to 2.5kHz and would rather employ them as the stereo woofers over the range 20 - 250 Hz; use two mid-range and two tweeters of choice.
Of course the B139, B110 and T27 were a good match and set the stage in the 60s, 70s and 80s for what is now known to be high end audio .
Many of us would vouch that the B139 was one of the best woofers ever built.
Personally I would not use B139 as subs since they are quite capable of frequencies up to 2.5kHz and would rather employ them as the stereo woofers over the range 20 - 250 Hz; use two mid-range and two tweeters of choice.
Of course the B139, B110 and T27 were a good match and set the stage in the 60s, 70s and 80s for what is now known to be high end audio .
Many of us would vouch that the B139 was one of the best woofers ever built.
Nico, thanks for the spec sheets-I was just thinking about the cut out last night and whether my calipers will extend far enough to measure, so that's a great help.
I've already pulled my own TS spec off them-alas quality control wasn't what it is now and they are considerabley diffierent in spec-I've played with the two spec in HR and with my proposed enclosure and deemed it acceptable for sub duties, at least until I can find another B139, I wouldn't have thought for a wider range of reproduction they would work too well.
I've already pulled my own TS spec off them-alas quality control wasn't what it is now and they are considerabley diffierent in spec-I've played with the two spec in HR and with my proposed enclosure and deemed it acceptable for sub duties, at least until I can find another B139, I wouldn't have thought for a wider range of reproduction they would work too well.
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Leaving speaker design aside, which I don't do because my friend's diy speakers sounded so bad. I buy and repair old blown up amps. The cheapest to repair was a blown up dynakit ST120 ($50), which is widely reviled for poor sound and bad heatsinks. The djoffe 10 transistor ($.07 each) bias mod fixed the sound www.diyaudio.com/forums/solid-state/156627-dynaco-stereo-120-can-beautiful.html and good heatsinks can be had in the trash at a food plant as blown up VFD (motor drives). With 5 transistors per channel this model was so easy to repair I did it without a schematic diagram and with no help from the internet or anybody. You could scratch build one of these on perfboard or lexan (which I built the joffe boards on) in a steel file box if you find a 70V transformer or switcher supply. Only 5 e-caps. (forget the voltage regulator board) 60 W/ch is plenty for these 101 db @1 W speakers in my living room. By contrast I've been fooling with trying to repair a $55 PV1.3k amp for over a year and the bag of blown up stuff has more than 60 parts. So don't buy that model.
Any old consumer amp even if working will need new electrolytic caps, and probably controls. A packaged solution will have not-enough inputs for your setup. I'm looking at improving my TV sound also, with HDTV converter, DTV converter, DVD recorder, DVD player, and VHS player as stereo sources. All have different output levels, and although the television switches those inputs okay, adjusting the levels at every switchover is a nuisance. I'm implementing a PA mixer under the coffee table to balance all the sound levels, and run a stereo amp into the T-300 speaker pair. It would run off RCA jack panels from switchcraft wired up as Y's, to split the sound from each source. That way I can watch the news or sports without turning the sound system on.
Used bar band setups are quite economic, particularly if you catch the band as they are breaking up and need the cash NOW before somebody is due to move away. With my SP2-XT speakers and stands (which sound superb) I got a 12 input Peavey Unity mixer (output channel blown) , CS800s amp (great sound, input capacitors were toasted, needs a PS recap because blows breaker sometimes),stereo graphic equalizer,digitech quad 4 stereo effect (400 effects some useful for the organ), rack case. This is diyaudio, I view repair as diy.
I'm using a $15 RA88a disco mixer as the hub of my music room system.It took $20 in parts (op amps, external power supply) to make it sound good. www.diyaudio.com/forums/analog-line-level/164102-improving-disco-mixer-mid-fi-performance.html That has three inputs, record turntable, CD player, FM radio. The three inputs can all be left on all the time unlike a preamp which has to be switched, and the levels stay balanced except for source material variations.
My ST70 amp has been a great bargain at $60 purchase and $10 in caps and output tubes over the years (three sets). But you would have to be there in 1972 when I bought it and the minister was leaving the country in 3 days. They are about $600 now used and in poor repair.
Any old consumer amp even if working will need new electrolytic caps, and probably controls. A packaged solution will have not-enough inputs for your setup. I'm looking at improving my TV sound also, with HDTV converter, DTV converter, DVD recorder, DVD player, and VHS player as stereo sources. All have different output levels, and although the television switches those inputs okay, adjusting the levels at every switchover is a nuisance. I'm implementing a PA mixer under the coffee table to balance all the sound levels, and run a stereo amp into the T-300 speaker pair. It would run off RCA jack panels from switchcraft wired up as Y's, to split the sound from each source. That way I can watch the news or sports without turning the sound system on.
Used bar band setups are quite economic, particularly if you catch the band as they are breaking up and need the cash NOW before somebody is due to move away. With my SP2-XT speakers and stands (which sound superb) I got a 12 input Peavey Unity mixer (output channel blown) , CS800s amp (great sound, input capacitors were toasted, needs a PS recap because blows breaker sometimes),stereo graphic equalizer,digitech quad 4 stereo effect (400 effects some useful for the organ), rack case. This is diyaudio, I view repair as diy.
I'm using a $15 RA88a disco mixer as the hub of my music room system.It took $20 in parts (op amps, external power supply) to make it sound good. www.diyaudio.com/forums/analog-line-level/164102-improving-disco-mixer-mid-fi-performance.html That has three inputs, record turntable, CD player, FM radio. The three inputs can all be left on all the time unlike a preamp which has to be switched, and the levels stay balanced except for source material variations.
My ST70 amp has been a great bargain at $60 purchase and $10 in caps and output tubes over the years (three sets). But you would have to be there in 1972 when I bought it and the minister was leaving the country in 3 days. They are about $600 now used and in poor repair.
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Make sure to 'exercise' the speakers before measuring TS if they have been sitting unused for a long while (some will show problems even after a few weeks). The best way would be to drive them free air with LF noise (ad that includes some subsonic content) at low power (not to exceed excursion) for a while - and some do need a good 3-4 days. The same applies to new out-of-the-box speakers. Without doing this it can be rather amazing how much they can deviate from factory spec. A simpler alternative is a small wall-wart transformer with an AC output, a few V will already do the trick, but this might take longer if the speakers resonance is far from 50Hz. This of course applies to larger cone units.
Also regarding your project in general, you will have to deal with edge diffraction issues on tweeters as well as baffle step compensation, two issues which rarely come up in car system design... A further thing to consider in a multi-way speaker with large excursion units operating below 300Hz or less, if you have two, you might consider mounting them on the sides in a distortion cancelling push-pull arrangement. This makes them operate mechanically in counter-phase so vibrations transmitted to the cabinet cancel out, while they still operate in phase acoustically.
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