Vikash said:
Vik,
I've enjoyed reading about all your fun at the UK meetup.
If you are going down the squeezebox route (and I' heartily recommend that, owning 4 of them at the moment (2 for speaker based systems - 2 for headphone only)) I've posted here and on head-fi under the same name.
The point I was going to make in this thread-crash (sorry! 😉 ) was that one of the fun features of the SB architecture is the ability to add software plugins - in particular the
Inguz Plug In for Digital Room Correction (DRC)
There have been several threads on it over at the slimdevices forums for more info.
Something that may appeal to you and other audio DIY'ers - and its much cheaper than going down the dedicated hardware/TaCT based route.
Regards
Grahame.
P.S. My other posts here mostly relate to trying to get the best out of some much loved '70's vintage Celestion 66's obtained second-hand for a mere 100 quid in the mid eighties - How DIY is that!
Vikash said:
An all pass delay network, whilst effective, doesn't apply infinitely variable delay on a per frequency basis. So you still have more power to play with.
Linkwitz is really talking about units such as the Behringer DCX. I had something more powerful in mind. Such as 30k+ taps on an FIR filter giving effectively 30,000 points of frequency and phase shaping. These points can be manipulated and shaped with target curves that are created in software and the curves can either be drawn or taken from presets.
So in effect you measure your drivers in semi-anechoic conditions and mounted in the final cabinet. This data is imported into the filter generation software such as "Acourate". From here the software takes a look at the response and you decide just what you want to do with that response. Do you want to flatten the entire passband of the driver to within +/-0.5dB and/or do you wish to extend the passband of the driver another octave either side of the drivers original passband in order to facilitate more ideal rolloff characteristics? There's an infinite number of options and all this is quite easily achieved for someone who is familiar with what makes up a technically correct speaker - subjective tuning comes later on.
After you've done this you then apply the crossover filter transfer functions to your 'corrected' driver response. Then apply the filter, re-measure in semi anechoic conditions to confirm filter performance.
The upshot of all this is your filters almost perfectly mimic the required acoustic rolloffs(ie. the transfer function of your filters is correct in the acoustic domain rather than just the electric) and the pass bands of the drivers are flat and level matched. You can then look into things such as symetrically matching the slopes on both the high and low pass around the XO point for excellent phase and frequency response characteristics etc. Out of all this a linear system(or making the best out of a bad situation) is born.
Now once you take your loudspeaker out of the semi anechoic environment in which it was measured, setup and, as a result, subsequently performed as a near linear system you'll find all has gone to pot as you now have room influences affecting the performance. Whats important here though is that you can determine that any deviation from the semi anechoic response is room related.
You then proceed to add the DRC components(FIR filters similar to the driver correction types used above) to help smooth the worse of the room problems lower down. Extra care must be taken at this stage though because excessive DRC can sound worse than no DRC. But because we're working from a solid grounding after the all that semi anechoic filter generation work you can confidently move forward knowing that the speakers are 'correct' and the rest is a balance between room correction and what sounds subjectively right to you. Where people using DRC often go wrong is trying to mash the in-room loudspeaker performance back to that of the near perfect semi anechoic measured performance - it can very rarely be done with just digital methods. My suggestion is only correct upto 400 or 500hz then use physical treatments above 800-1Khz. This allows the treatments to discrete and rather more minimal because your only dealing with upper frequencies and the bass, which needs huge and impractical treatments, is dealt with digitally.
There's obviously more to it than just this basic outline but I'm sure you can see its has power and flexibility like nothing else. Which brings about the question of just what will it do, if at all, to enhance the sound over the Linkwitz' already excellent implementation? Nothing is for nothing so I have no definite answer for that but I'm confident you could build upon Linkwitz' work to further enhance the performance and better tailor the speaker to the listening environment.
BTW If your source is digital then you'll be keeping the signal chain entirely digital right up to the amps. Further performance gain can be got by looking at some very nice external master clocks/DAC combos.
Its a shame I didn't do the presentation over the weekend during the meet. It was intended to be an indepth and practical demonstration of the points I've mentioned here. Much of this is more easily explained with graphs and visual examples.
Finally don't get me wrong, its definitely not all a bed of roses but the potential upshots are an accuracy of sound that you'd struggle hard to find in other filter technologies. Whether that is your 'thing' is another less black and white topic 🙂
How do you do that? Just sit back and enjoy the kit? 😉
Could someone please summarize what configurations we were listening to Chris's speakers in? And what the differences in sound were for any given component change.
I have no idea what sources/amps we were listening to at any one time, i heard a change of amp which made quiet a difference.....
Maybe stick with noting the positive differences in sound, so as not to upset anyone.....
I have no idea what sources/amps we were listening to at any one time, i heard a change of amp which made quiet a difference.....
Maybe stick with noting the positive differences in sound, so as not to upset anyone.....
Mark25 said:
SimontY said:
lol! I'm not saying anything, I don't want to put my foot in it.
As said previously, the room acoustics were terrible. So it is very difficult to be really objective.
I was surprised by the open baffle speakers on show and also the sound from the small full range speakers. Suffice to say that on my next break from work, the saw will come out!!
Andy
Mark, the source was a stock Marantz, (CD63/67?), the pre was a class A jobbie of some kind, and the amps were firstly Chris's Zen, and then secondly, Hugo's AXs.
What's happened to Chris, has all the praise scared him away? 🙂
What's happened to Chris, has all the praise scared him away? 🙂
Hi, Still here. I’ve no ISP at home yet and have been on a 4 day 1st aid course so couldn’t post.
Thank you for all the positive comments regarding the “Toblerones”.
I enjoyed making and finishing them and indeed only now getting to listening to them. As RAndyB demonstrated to me on the Saturday, BSC is required for the most accurate reproduction. “The Edge” is useful to determine the component values to use for an active op-amp based BSC circuit alternatively some people use an inductor from amp to speaker. I certainly make no claims to the design and as has been pointed out this is up on the Jordan site. I have been attributing the design of them to GM (Greg Montfort) I hope this is right?
Philpoole the ‘rest’ in the photo Post #657: Pass Zen V7T, a 2u high 19” rack MikeB sysmasym, the box with 6 knobs is a stereo one band parametric EQ and the two grey boxes are RAndyB’s active BSC “widget”. Mark25 you possibly witnessed the difference the BSC circuit made and the sysmasym to Zen swap.
If only I had a bigger car I would have brought the PSU for the 6 channel UCD180’s and we could have tried them with Viks Orions. Next time perhaps.
Vikash: We were perhaps talking a cross purposes. I am aware of SL’s thoughts on replacing the ASP with DSP. I had been impressed by Jans demo of his modified DCX and have now got one to mod. I would probably only use this to determine crossover requirements for 2 and 3 way speakers before using active op-amps crossovers.
I was also impressed the Lightspeed attenuator (Sorry I didn’t get your name but I assume you were float?). It goes to show ‘less is more’ if you don’t need the extra gain of a line stage. If you are prepared to match LDR’s you can build a 6 channel one for HT use (or DCX). This will be of my next projects…
Al, Heretical, I have though about building one. I guess these triode are a tad to big?
DC servo at 5KV could be tricky!
The UV glow from the mercury arc can double as purple power on indicator!
I suppose they could be used as a direct drive ESL amp? Unusual bedside reading lamp perhaps?
Chris.
Thank you for all the positive comments regarding the “Toblerones”.
I enjoyed making and finishing them and indeed only now getting to listening to them. As RAndyB demonstrated to me on the Saturday, BSC is required for the most accurate reproduction. “The Edge” is useful to determine the component values to use for an active op-amp based BSC circuit alternatively some people use an inductor from amp to speaker. I certainly make no claims to the design and as has been pointed out this is up on the Jordan site. I have been attributing the design of them to GM (Greg Montfort) I hope this is right?
Philpoole the ‘rest’ in the photo Post #657: Pass Zen V7T, a 2u high 19” rack MikeB sysmasym, the box with 6 knobs is a stereo one band parametric EQ and the two grey boxes are RAndyB’s active BSC “widget”. Mark25 you possibly witnessed the difference the BSC circuit made and the sysmasym to Zen swap.
If only I had a bigger car I would have brought the PSU for the 6 channel UCD180’s and we could have tried them with Viks Orions. Next time perhaps.
Vikash: We were perhaps talking a cross purposes. I am aware of SL’s thoughts on replacing the ASP with DSP. I had been impressed by Jans demo of his modified DCX and have now got one to mod. I would probably only use this to determine crossover requirements for 2 and 3 way speakers before using active op-amps crossovers.
I was also impressed the Lightspeed attenuator (Sorry I didn’t get your name but I assume you were float?). It goes to show ‘less is more’ if you don’t need the extra gain of a line stage. If you are prepared to match LDR’s you can build a 6 channel one for HT use (or DCX). This will be of my next projects…
Al, Heretical, I have though about building one. I guess these triode are a tad to big?
DC servo at 5KV could be tricky!
The UV glow from the mercury arc can double as purple power on indicator!
I suppose they could be used as a direct drive ESL amp? Unusual bedside reading lamp perhaps?
Chris.
Aaaaaaaahh.........
That explains a few things! That was the most precise bass i've ever heard. From that limited demo i would say active BSC is a much better way of getting bass out of a speaker system than adding a "resonance that is not under direct control of the amplifier".
The only problem would be how much power you can throw at the driver. If the <BS frequencies are given the full 6db lift, that's an enormous amount of power @ L.F. Probably why 4" drivers were able to produce bass that you could feel and not hear, below 28Hz, and shake the Church floor. I have a feeling they wouldn't put up with that all day.
Personally; what i found impressive was the linearity of the <150Hz frequency reproduction. There was no bloom or boom at any particular bass frequency. This led to a very natural sound, in which the bass dissapeared totally when there was no bass content, which had the effect of enhancing the non-bass music content.
What i also liked was the lack of any overhang in the bass notes themselves, they came across very clean and coherent, not artificially fast or anything, just very natural. There was also good definition between the different types of bass notes.
Mark25 said:
As my speakers use two mid/bass drivers I've been able to try both methods - 1) using a 2-way xover and active BSC. And 2) using the speakers as 2.5-way (ie. 2 way but with 2nd driver just there for BSC). This obviously requires a large and hence expensive coil.
I can't put my finger on why but I prefer the latter option.
I'd expect two or more of those 4" Jordans would sound even better. They'd go fairly loud with 4 but it'd start to get expensive. I'd also love to hear them with a tweeter crossed over at around 5-8khz to just lift the treble a touch. I can't help but think that would sound fantastic.
SimontY said:
I use 100mm full-range at home myself, but CCS 125 FR's. I have a very bright phono stage which complements them very, very well. The lower bass however, is non-existant.
Well, that's what the transmission line is for. 😀 I've also heard an IPL Acoustics 6.5" aluminum driver in a T line and the bass was gloriously deep, rich and tuneful, especially for a small driver. I'm sure a pair of these was meant to be at the meet, but I didn't see them 🙁
SimontY said:
I was thoroughly impressed by the Jordan JX92S. The sound was far more than the parts would have led you to expect.
Jordan do another interesting driver:
An externally hosted image should be here but it was not working when we last tested it.
http://www.ejjordan.co.uk/drivers/jxr6.html
This is a 2" driver which looks to have a flat and usable operating range of around 120hz upto just over 20Khz. Compared to JX92S it trades low end extension for more highs and better directivity.
The interesting thing is that it can be stacked to create a vertical array with fairly close C-to-C spacing. Jordan recommends 4 per side coupled to your choice of bass driver and loading. The upshot being you'd boost sensitivity and lower distortion through through coupling as well as allow for greater headroom with the dedicated bass driver(s).
I wouldn't mind hearing that sort of setup 😉
SimontY said:
Simon,
it's harmonics from 5kHz up, which allows you to differentiate between a clarinet and a flute. Adding a crossover can seriously damage your waveforms. To my elderly ears it isn't helpful, because I can tell the difference between the instruments via my JX92Ss without a tweeter. (insert your own age-ist joke here)
ShinOBIWAN said:
Ant,
Mr Chris and I had our own Jordan inspired mini-meet the following weekend. Chris brought the latest Hypex amplifier modules - if he had brought them to Chesterfield you would have been even more amazed at what the JX92S can do - tighter bass, more detail, better top end - shall buy some soon because even my wife was impressed.
Andy
RAndyB said:
That's an interesting point Andy. So what you'd gain in being able to hear cymbals and harmonics you'd lose in those parts being somewhat distorted. What troubled me was hearing what sounded like bursts of noise in Krall's Temptation and not understanding what instrument it was. When I heard it next at home I heard it was a tambourine.
Clearly you're just choosing one trade-off over another.
But let's be clear - in some ways those Jordans sounded far less distorted than my conventional 2.5 way speakers (crossed at 5khz).
Simon
I've just come back from a weeks holiday, and have read the last 4 pages with great interest..
Ed (vitalstates) and my self and scott All live in close proximity and have regualar meets..
I was quite suprised by the amount of solid state equipment.. and the lack of equipment shown on the saturday to be honest,
I was also suprised by the difference in what people thought as a 'good sound'.
I had some very interesting conversations and thoughly enjoyed the day.
I demo'd my latest OB speakers.. the 3 rd or 4th version this year,,
they are lowther ex4 supported by goodmans axiom 301 and goodmans audiom 61.. all are full range speakers in there own right..
the amp was a very simple single ended using 1930's valves 41mp driving cosser 2p into tribute amorphous iron..
valve amps are jusdge by the inexperenced on the output valve, which in the case of the 2P, no one will have heard of...
but its sound is very similar to the famous PX4 valve but half the power.
With after thought.. i used the 'wrong' amp on the day with my OB speakers due to the room,
i had another amp with me that is slightly leaner that would have suited the room better as the reflections tended to exagerate and cloud the detail in the music.
i read recentley in a book from 1957 that people can judge sytems based on the type of music and if they also listen to mostly hi fi or live music.
on holiday there was a bar with a very good jazz group, playing proper instruments, drums, trumpet piano etc
that is the type of sound i want my sytems to recreate (as in the tones and harmonics and musical peaks that where present, so far.. i'm as close to getting that, as i've heard.. so far!!.
I don't mean that that my system or that valves are only any good for jazz music.. i play all sorts, heavy rock and love 'dance' music from nothern soul up to the present
Totally flat speakers are to me not that important (but are important!)
But, as i've not yet heard any correction circuits that don't start to filter the 'life' out of the sound. how ever slight. I'm am more than happy with the full range route.
I was once a solid state/ yam NS1000 owner, But I had been a lowther horn convert for the last 10 years or so, but i had realised this year that the sound of Obs was something else, mainly due to the lack of colouration in the bass,
But getting good bass is quite a job from OB's the amp/ speaker combination is vital, as are good quality speakers with high power motors to give both good damping and a fast ride. and having heard many of the eminace based drivers, i was not that impressed (but impressed enough to try OB..)
A friend of mine used to play in a rock group in the 60's and 70's, Free once used their set up at Bridington Spa.. Goodmans 301's and audiums where the amongst the best drivers at the time,
They found the 15 inch speakers sounded 'wooly' so prefered multiple 12" speakers for a 'tighter' sound, i must say i have to agree.. after listening to what mine produce.
its not until you get used to the sounds that a good amp and good drivers in OB produce that you 'start' to hear the issues that are unfortunately there with 'boxes'.. there are issues with OB's too but i seem to have sorted them to my satisfaction.. 'my' being the best discription..
so i'm a bit of a convert to OB's at the moment.
thanks for the nice comments about my set up, i do apprecate the sound it makes is not the usual hi fi sound, nor do i want it too .. and that does make it into not everyones cup of tea..
....but i'm happy..
steve
Ed (vitalstates) and my self and scott All live in close proximity and have regualar meets..
I was quite suprised by the amount of solid state equipment.. and the lack of equipment shown on the saturday to be honest,
I was also suprised by the difference in what people thought as a 'good sound'.
I had some very interesting conversations and thoughly enjoyed the day.
I demo'd my latest OB speakers.. the 3 rd or 4th version this year,,
they are lowther ex4 supported by goodmans axiom 301 and goodmans audiom 61.. all are full range speakers in there own right..
the amp was a very simple single ended using 1930's valves 41mp driving cosser 2p into tribute amorphous iron..
valve amps are jusdge by the inexperenced on the output valve, which in the case of the 2P, no one will have heard of...
but its sound is very similar to the famous PX4 valve but half the power.
With after thought.. i used the 'wrong' amp on the day with my OB speakers due to the room,
i had another amp with me that is slightly leaner that would have suited the room better as the reflections tended to exagerate and cloud the detail in the music.
i read recentley in a book from 1957 that people can judge sytems based on the type of music and if they also listen to mostly hi fi or live music.
on holiday there was a bar with a very good jazz group, playing proper instruments, drums, trumpet piano etc
that is the type of sound i want my sytems to recreate (as in the tones and harmonics and musical peaks that where present, so far.. i'm as close to getting that, as i've heard.. so far!!.
I don't mean that that my system or that valves are only any good for jazz music.. i play all sorts, heavy rock and love 'dance' music from nothern soul up to the present
Totally flat speakers are to me not that important (but are important!)
But, as i've not yet heard any correction circuits that don't start to filter the 'life' out of the sound. how ever slight. I'm am more than happy with the full range route.
I was once a solid state/ yam NS1000 owner, But I had been a lowther horn convert for the last 10 years or so, but i had realised this year that the sound of Obs was something else, mainly due to the lack of colouration in the bass,
But getting good bass is quite a job from OB's the amp/ speaker combination is vital, as are good quality speakers with high power motors to give both good damping and a fast ride. and having heard many of the eminace based drivers, i was not that impressed (but impressed enough to try OB..)
A friend of mine used to play in a rock group in the 60's and 70's, Free once used their set up at Bridington Spa.. Goodmans 301's and audiums where the amongst the best drivers at the time,
They found the 15 inch speakers sounded 'wooly' so prefered multiple 12" speakers for a 'tighter' sound, i must say i have to agree.. after listening to what mine produce.
its not until you get used to the sounds that a good amp and good drivers in OB produce that you 'start' to hear the issues that are unfortunately there with 'boxes'.. there are issues with OB's too but i seem to have sorted them to my satisfaction.. 'my' being the best discription..
so i'm a bit of a convert to OB's at the moment.
thanks for the nice comments about my set up, i do apprecate the sound it makes is not the usual hi fi sound, nor do i want it too .. and that does make it into not everyones cup of tea..
....but i'm happy..
steve
Steve,
Thanks for the background into the system you demonstrated on Saturday. I chatted to you very briefly, I think to say that I'd heard those Goodmans drivers before (in a massive box) and was extremely impressed.
I was also very impressed by the detail and cleanness of your speakers. I don't know if it's a sound I would get on with long term but I can understand the appeal (I think I actually like some colouration so as to avoid harshness). I'd really love to try something like you've made one day.
Thanks for the background into the system you demonstrated on Saturday. I chatted to you very briefly, I think to say that I'd heard those Goodmans drivers before (in a massive box) and was extremely impressed.
I was also very impressed by the detail and cleanness of your speakers. I don't know if it's a sound I would get on with long term but I can understand the appeal (I think I actually like some colouration so as to avoid harshness). I'd really love to try something like you've made one day.
OFF TOPIC
A neighbour from across the road just came round... I've had Eric Clapton, Diana Krall and Supertramp on so much louder, but when I play Whigfield, Alexia and the Vengaboys suddenly he can hear it through his double glazing!
A neighbour from across the road just came round... I've had Eric Clapton, Diana Krall and Supertramp on so much louder, but when I play Whigfield, Alexia and the Vengaboys suddenly he can hear it through his double glazing!
- Status
- Not open for further replies.