I doubt this would interest many but I will give it a try. I had a TV that worked nicely through Scart to a FM transmitter. Very useful late at night. The very old hard-drive video recorder never had anything better. The new LG TV has no audio output except Scart or digital. It has a 3.5 mm stereo for input only, no headphone socket. Scart out from TV did the usual, Scart loop did not. So I did something very bad. I paralelled the videos RCA's outputs and TV Scart out. Sure enough it worked albeit very badly. The video crackled when near clipping and the TV sounded dull. Version two had 2 by 220R. The video was great and TV nearly mute. The solution was video 220R and TV zero R. That is a mystery but infered from the one must never do version one. 220R should be better than a dead short plus whatever is inside the op amps. Step four, that has been avoided. That was to use the Scart pulse presuming it there to work a relay via a buffer. I was pleased to avoid that. There is a minor trade off. The video side has slight hum due to the resistor ( proximity of TV mostly ). As the video is poor on hum it is hardly noticed.
The two outputs are common as the video has a TV/Video changeover. When used both sound sources are heard. Alas it was the video that was not in the loop so wasn't a solution if wondering. That is it would not give a simultaneous in and out. The old TV did.
This is very typical of how crossovers work or rather don't work. As far as I can see the public does not want active as they feel more comfortable with chop and change upgrades. In motorcars this is a thing of the past. It would not be so if polution control hadn't happened I guess? I would much rather have a manual control carburettor.
On the OB speakers I am learning mediocre source material needs exceptional speakers. As I have that already I have become complacent. Creating a speaker to play everything is very very hard. The oddest thing is outside of the listening room a rather high level of perfection is happening. The nearer field is less so. Voice training is required. And maybe they never will totally sing? Very odd and sort of wonderful because of it. The plywood baffle I would liken to a runnner who didn't warm up. It is like all the muscles are tight. The low mass bafffle wasn't like that. It makes me question all speakers. I suspect the rubber roll surrounds are they only thing that saves the day?
The two outputs are common as the video has a TV/Video changeover. When used both sound sources are heard. Alas it was the video that was not in the loop so wasn't a solution if wondering. That is it would not give a simultaneous in and out. The old TV did.
This is very typical of how crossovers work or rather don't work. As far as I can see the public does not want active as they feel more comfortable with chop and change upgrades. In motorcars this is a thing of the past. It would not be so if polution control hadn't happened I guess? I would much rather have a manual control carburettor.
On the OB speakers I am learning mediocre source material needs exceptional speakers. As I have that already I have become complacent. Creating a speaker to play everything is very very hard. The oddest thing is outside of the listening room a rather high level of perfection is happening. The nearer field is less so. Voice training is required. And maybe they never will totally sing? Very odd and sort of wonderful because of it. The plywood baffle I would liken to a runnner who didn't warm up. It is like all the muscles are tight. The low mass bafffle wasn't like that. It makes me question all speakers. I suspect the rubber roll surrounds are they only thing that saves the day?
Dejan, as you know I look at the system as a whole, that's how I judge the outcome - I've heard Dynaudio brand speakers sound superb, and bloody awful - so I wouldn't pass judgement myself in such a fashion. Of course, certain characteristics will always be there, and if the system is in relatively poor shape then the "weaknesses" of the drivers will come through very obviously - maybe this is what's happening with their woofers ..
I guess that's where we have a disconnect they all sound the same to me.
If people want chop and change then they'll "reap the reward" - as in, always less than the optimum sound that the system is inherently capable of producing,
. Part of my years long battle was to stabilise achieving quality sound, this by far was the most frustrating aspect of everything - the slightest wrong move and the SQ would plummet, because something was out of kilter - and previous steps would need to be retraced, serious detective work go into it, to work out what had "gone wrong".A very major learning curve was needed, and is still going on, to get a handle on making producing optimum sound "robust" - to be able to achieve it at will, and have it maintain in spite of external carryings on ...
They will sing, Nige. You're 'learning',
, that the closer you get to convincing sound always being there, the harder it is to get complete control over the situation - the frustration can be immense at times! However, persist - the rewards are enormous!!The system needs to be exceptional, not just the speakers, that's the key - one tiny, tiny defect in the system, somewhere, can drag the whole shebang down to almost being unlistenable to - and the major headache then is locating that single, isolated gremlin - doing a million, other, easy, "fixes" is just avoiding the issue - you could spend years going around and around in circles, never actually getting genuinely better sound - because that key weakness at the heart of it is still not being addressed.
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Hmmm ... I thought I saw this following passage before somewhere, but it can't have been diyAudio - I can't find a reference to it. Anyway, from the Gm Amp. | lab jc:
. ... Doesn't happen very often with gear, but certainly no magic is needed to make it occur - just a well sorted out system. The shame of it is that it is so rare, and so much of current audio thinking mitigates against it happening more often ... .
Luckily, he's wrong,
. ... Doesn't happen very often with gear, but certainly no magic is needed to make it occur - just a well sorted out system. The shame of it is that it is so rare, and so much of current audio thinking mitigates against it happening more often ... .
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Luckily, he's wrong,
Any sufficiently advanced technology is indistinguishable from magic Frank
With all this going on what is happening with your Quad 303 project?
Fear and work has taken over. The main thing is I want to go to my friends workshop to do some wood and metal work. I have a product coming for him to look at also. In addition I have a turntable project I am helping with.
One thing I feel I must say. The simple 12 Lta drive unit I took to be a very low colouration driver. On a traditional baffle it is not. So all of the specail drive units we see might only be the rubber suround? This is logical. The shape of the cone must be the major limitation. Next is mass total . Compliance. Size. And finally brakup modes. Paper deals with that well. If I am right the speaker boxes are universally bad news. Materials first and that it is a box as the killer blow. The Klipsche Forte 2 looks thrown together out of good quality ply. The speaker is remarkably free of the problems I get. The drive units look similar. I have to respect them as that is not easy. Most would not buy a Klipsche. That's odd as they can sound very real. They look like disco speakers perhaps as to why?
I have come up with a cunning plan for the Quad clone. I have some 7 mH chokes of 20 amps capacity. These can be configured as 3.5 or 14 mH also. What I might do is fit the 15 inch bass units using these to cut above 250 Hz. The coupling via 4700 uF 100 V. The 12 Lta can be with 100 uF 100 V coupling and tweeter with 2u2 250 V . This way I can use bass boost and one amp as the curve is flat at 250 Hz. The impedance curve being slightly better than allowing the 15 inch unit to sit there in simple paralell. In the end I can use both amps.
I have worked out how to use a low mass baffle. I will return to it. Basically I use a small 1/2 inch thick ply square to take 12 Lta and tweeter. This will bolt to the polystyrene with long bolts ( 4 ) and mudguard washers so as to be in compression. If wanting better a similar 1/4 inch ply square to the rear. To finish a rebated frame to offer protection. In a minamalist way the polystyrene has a nice look. If anything it has more bass. Perhaps because the hash of the stored energy is masking the bass?
I was doing 3 phase theory for a lady at work. Her father makes wind turbines . She would like to be up to speed. It is 42 years since my bit of paper on this. As best I can see the voltage 3 phase is Tan 120 degrees. This is like Tan 60. O/A = tan. That is root / 3. Thus 230 V single phase is 398.362 V three phase ( 381 V @ 220 V and 415.7 V 240 V ). I seem to remember there was a much more simple geometric proof ?
Frank. It is so weird. The further I get awy from the sound the more real it is. I think I know why. Simply this. If you have box speakers this becomes the difficult one. The reason is the speaker is like a highly directional microphone. Bose might be right to do what they do. It might make the box more invisible. I speculate that Bose never were able to make the next leap forward by adding a tweeter to the 901's. It just didn't work. Thus to wind a 0R9 driver was their best option. 9x 0.9 = 8R1.
I have the opposite problem to most. The large baffle is giving colouration to the sound. Some assume the size of the baffle to be this colouration. All seem to write this way. I suspect the frequency ripples are not very important compared with the delayed energy.
The silly TV solution was pleasing. It is actually far better than it should be. I assume the FM transmitter has a self limiting action. When using the double 220R it produced a near zero output in the Scart connection. Perhaps it was falling outside the limiter range? As far as I can see the op amps are safe doing this. Distortion is OK and such a simple solution. The Dyson vacuum cleaner caught fire the other day. It was the belt to the brush. My son being lazy let the brush jam up. It was like how cave men made fires. It looked so likely to be carbon brushes as it is the motor area. £3.60 including shipping for the belts ( 1 spare ). I mention this as the Dyson is as rediculous as my paralell op amps solution. Dyson take the drive directly off of the motor shaft with no retaing groove. Having tried this with turntables I have had no sucess. I respect them as the spare part works very well. The engineering is in the belt and so cheap ! My son said " Dad this will be done by 3 D printers soon ". I don't think so, it's the web of cords that make it possible. How I longed for 1950's Grundig belts for my turntables with cloth backs ( Dejan was first to say this ). If you have a Dyson do not take it all apart. The new belt being a rubber type material will stretch well enough to get it on. You need someone to help if so. Just remove the brush cover to get access.
The old TV was first generation LED. It is slightly superiour to the replacement. The new one cost £140 - £40 - £10 ( voucher ) = £90 24 inch LG. A new switch-mode £18 plus postage , out of stock. The out of stock was the crunch. I gave it to my friend and general repairer Richard Franklin in Kidlington Oxon. Richard repairs anything and has things like PL12 D for £80 to sell. When the TV is fixed it might be £65. I think I will happily pay that and have it back. Funny I should be unwilling to fix a TV yet happy to fix a vacuum cleaner! I suspect the TV is no more difficult. The new TV has a far better guide and simple menu. For that it is nice to have. It's sound is slightly better also. The only reason I wrote about this is I suspect it is a very good way of making a preamp. That is to simply short the sections not required. It might have value? J FET shorting I think has been used ? A relay might be better ? I have used a noise gate on a phono stage done this way. It completely fools people. A simple comparator which detects vinyl noise to say switch on. It is so quick as to never be detected. 100 dB signal to noise! The point is even if only 60 dB the LP is always able to swamp it. The TV solution the same . - 80 dB hum at a guess - 70 dB from the hard-drive PSU. The hum is rumble ! Daewoo knew about it as it has no bass below 100 Hz. It's all SMD so I never tried to fix it. 40 GB and 40 Hours recording and a 2005 product code in the memory. It has lasted well. It must be like DivX compression, it is as good as SD transmission quality. I tried fitting a larger hard drive. It wouldn't format it. The downstaires one is 360 hour and excellent. Some how the extra space isn't doing much. I mostly use the old one!
I have the opposite problem to most. The large baffle is giving colouration to the sound. Some assume the size of the baffle to be this colouration. All seem to write this way. I suspect the frequency ripples are not very important compared with the delayed energy.
The silly TV solution was pleasing. It is actually far better than it should be. I assume the FM transmitter has a self limiting action. When using the double 220R it produced a near zero output in the Scart connection. Perhaps it was falling outside the limiter range? As far as I can see the op amps are safe doing this. Distortion is OK and such a simple solution. The Dyson vacuum cleaner caught fire the other day. It was the belt to the brush. My son being lazy let the brush jam up. It was like how cave men made fires. It looked so likely to be carbon brushes as it is the motor area. £3.60 including shipping for the belts ( 1 spare ). I mention this as the Dyson is as rediculous as my paralell op amps solution. Dyson take the drive directly off of the motor shaft with no retaing groove. Having tried this with turntables I have had no sucess. I respect them as the spare part works very well. The engineering is in the belt and so cheap ! My son said " Dad this will be done by 3 D printers soon ". I don't think so, it's the web of cords that make it possible. How I longed for 1950's Grundig belts for my turntables with cloth backs ( Dejan was first to say this ). If you have a Dyson do not take it all apart. The new belt being a rubber type material will stretch well enough to get it on. You need someone to help if so. Just remove the brush cover to get access.
The old TV was first generation LED. It is slightly superiour to the replacement. The new one cost £140 - £40 - £10 ( voucher ) = £90 24 inch LG. A new switch-mode £18 plus postage , out of stock. The out of stock was the crunch. I gave it to my friend and general repairer Richard Franklin in Kidlington Oxon. Richard repairs anything and has things like PL12 D for £80 to sell. When the TV is fixed it might be £65. I think I will happily pay that and have it back. Funny I should be unwilling to fix a TV yet happy to fix a vacuum cleaner! I suspect the TV is no more difficult. The new TV has a far better guide and simple menu. For that it is nice to have. It's sound is slightly better also. The only reason I wrote about this is I suspect it is a very good way of making a preamp. That is to simply short the sections not required. It might have value? J FET shorting I think has been used ? A relay might be better ? I have used a noise gate on a phono stage done this way. It completely fools people. A simple comparator which detects vinyl noise to say switch on. It is so quick as to never be detected. 100 dB signal to noise! The point is even if only 60 dB the LP is always able to swamp it. The TV solution the same . - 80 dB hum at a guess - 70 dB from the hard-drive PSU. The hum is rumble ! Daewoo knew about it as it has no bass below 100 Hz. It's all SMD so I never tried to fix it. 40 GB and 40 Hours recording and a 2005 product code in the memory. It has lasted well. It must be like DivX compression, it is as good as SD transmission quality. I tried fitting a larger hard drive. It wouldn't format it. The downstaires one is 360 hour and excellent. Some how the extra space isn't doing much. I mostly use the old one!
Nigel, I can't hear what you're hearing from your baffle speakers, but in 30 years I have never experienced the setup of the speakers to be the fundamental problem. If speakers do well at a distance but not so good closer, then my immediate verdict would be that the dynamics of the system are doing nicely, but the level of audible distortion is still too high - the further you are from them the less you hear problems, but once you get close enough these problem artifacts are quite obvious, and distracting. Now, it is always possible that the speakers are the fundamental problem, but IME this is extremely unlikely - your speakers are like a 'scope on system behaviour, and getting closer is like switching the sensitivity control to a finer setting - it becomes easier to "see the noise".
My approach would be to use a recording where the problems are particularly obvious, and say to myself, "Okay, this is not sounding good because I can hear a distortion somewhere in the system - from my experience, what is likely to be the cause of that type of distortion? Well, area or cause A is the most likely, so I will deliberately change something in area A, and see if I hear a difference - and proceed from there". I very deliberately do ... not ... "blame" ... the ... speaker - if I had done that, I would not have got anywhere in the last 30 years ...
My approach would be to use a recording where the problems are particularly obvious, and say to myself, "Okay, this is not sounding good because I can hear a distortion somewhere in the system - from my experience, what is likely to be the cause of that type of distortion? Well, area or cause A is the most likely, so I will deliberately change something in area A, and see if I hear a difference - and proceed from there". I very deliberately do ... not ... "blame" ... the ... speaker - if I had done that, I would not have got anywhere in the last 30 years ...
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I am being fussy mostly. One could say the tonality is vastly different polystyrene to plywood. In most engineering the polystyrene sheet is as useful as a chocolate screwdriver. This is the exception. Turntables using a ply motorboard sound a bit the same. I have used different drivers and had similar results.
Windows 8. ASUS A55 8AM mother-board seemed only to work with Windows 8. This meant I couldn't use many older programs. A Windows 3.1 emulator helped. Form this my son rebuilt my old Windows XP computer as the mother-board was OK. Since then I have been donated a very nice mother-board that runs Windows 7. Very easy to get along with and using it now. On buying someone a laptop this Christmas the guy in the shop said he understood that all Windows 8 users could get a free update to Windows 10 as 8 has troubles. Having said that glad I had got use to 8 as now when using laptops with it on it doesn't phase me. ASUS now have downloads to enable other uses including Linux I am told. As my son said both ASUS and Windows rush to get things out and then let us sort it out. I knew we were in for trouble when Linux wouldn't load. Like buses come in 3's I now have 3 computers and the house 6 in total. One has been turned into a server.
Windows 8. ASUS A55 8AM mother-board seemed only to work with Windows 8. This meant I couldn't use many older programs. A Windows 3.1 emulator helped. Form this my son rebuilt my old Windows XP computer as the mother-board was OK. Since then I have been donated a very nice mother-board that runs Windows 7. Very easy to get along with and using it now. On buying someone a laptop this Christmas the guy in the shop said he understood that all Windows 8 users could get a free update to Windows 10 as 8 has troubles. Having said that glad I had got use to 8 as now when using laptops with it on it doesn't phase me. ASUS now have downloads to enable other uses including Linux I am told. As my son said both ASUS and Windows rush to get things out and then let us sort it out. I knew we were in for trouble when Linux wouldn't load. Like buses come in 3's I now have 3 computers and the house 6 in total. One has been turned into a server.
I can agree that speakers are blamed by default, when in fact they are not the main culprit. On the other hand, we all know speakers are not all the same, some are simply better than others no matter what you do. My feeling is that this is caused by a misstep in putting the system together. I believe one shoud start with the speakers, wring whatever they are capable of delivering, and that can be a lot, really a lot. Then, when you have a firm footing, a pivot point so to speak, only then proceed with the rest of the system.
I did just that and never looked back, and if I did, it was in anger with myself for not doing it sooner. In that sense, I understand Nige doing effectively the same or very similar thing. Once he sorts out his speakers, and has a firm standard against which to copare everything else, it will be easier for him. How will he know when he gets to the point of diminidhing retruns with his speakers? Easy, they will sound very similar in any situation with almost any decent amp he attaches to it, and if he should choose to make the amp a monster, he will not lose by it for sure.
I did just that and never looked back, and if I did, it was in anger with myself for not doing it sooner. In that sense, I understand Nige doing effectively the same or very similar thing. Once he sorts out his speakers, and has a firm standard against which to copare everything else, it will be easier for him. How will he know when he gets to the point of diminidhing retruns with his speakers? Easy, they will sound very similar in any situation with almost any decent amp he attaches to it, and if he should choose to make the amp a monster, he will not lose by it for sure.
And I thought I was the locall nutter, when in fact I own only two PCs, one for regular work, and the other a chameleon (HDDs in replacable racks, so it can be Windows XP or Windows 7 Professional at a whim).
Obviously, delusions of grandeur on my part.
Add another 4 zeros and a gallon of snake oil, and I'll agree.
Paramount to whom?
Depeding o the goal, it may not be to me, the limit being what I have in my audio savings account. But price is NEVER paramount in the sense that I look at it first, I look at what that mpney gets me, and then compare with what I can afford. No doubs price is a facto, but it is NOT paramount to me in the sense that it overshadows everything.
The word "paramount" is the issue here. Obviously it will be the rule-all parameter if I am asked to pay like €15,000 for a phono stage alone, both because I don't believe any phono stage ever made is worth that kind of money and because I don't have that money. But I look at the price only after I have an idea whether I believe something is worth the effort, thus price is my secondary consideration.
Paramount to whom?
Depeding o the goal, it may not be to me, the limit being what I have in my audio savings account. But price is NEVER paramount in the sense that I look at it first, I look at what that mpney gets me, and then compare with what I can afford. No doubs price is a facto, but it is NOT paramount to me in the sense that it overshadows everything.
The word "paramount" is the issue here. Obviously it will be the rule-all parameter if I am asked to pay like €15,000 for a phono stage alone, both because I don't believe any phono stage ever made is worth that kind of money and because I don't have that money. But I look at the price only after I have an idea whether I believe something is worth the effort, thus price is my secondary consideration.
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