Wiz away chakster ;-)
16 ohm speakers: any amp sounds better with more resolution. speaker cables less critical.
First,
Thanks to anyone who responds with whatever answers/opinions/advice comes from this. I'm retired, covid bound, Donna is taking care of everything holiday related, too much time, always curious.
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I happened across this in an old thread started by Ralph (atmasphere)
"Sixteen ohms, BTW is a very simple means for getting more resolution out of your system, as nearly every amplifier made sounds better on 16 ohms than it will on 4 or 8 ohms. Speaker cables become far less critical too."
My speakers are 16 ohms (Electrovoice horn tweeter, horn mid, 15" woofer, crossover, rheostats, from 1958).
Extremely efficient, I have more than enough power. Amp, now and in the past all had 16 ohm taps.
Of course I can hook them up to my Cayin's 8 ohm taps now and listen, but facts, opinions, advice, to learn is good.
...........................
Lots of Questions?
1. why/how do 16 ohm speakers make amps sound better, with more resolution?
2. why speaker cables less critical? perhaps this is why I/we don't hear cable differences in my system?
I'm using my homemade twisted pair of cat 5 now (8 individually insulated small diameter solid core).
3. to get exterior bias control: use 8 ohm tap for my 16 ohm speakers? (get alternate amp 4/8 no 16 tap,)
lose advantage(s)? 'sounds better'; 'more resolution'; 'speaker cables less critical'?
this says slightly more mids:
http://blog.hughes-and-kettner.com/ohm-cooking-101-understanding-amps-speakers-and-impedance/
I can fine tune my speakers via their two rheostats: 'presence' and 'brilliance', so not really an issue for me.
4. Importance of Bias Control
how important is Bias? (I don't care about heat, power output, or tube life, just as bias affects sound). Frankly, using vintage tube receiver Fisher 500C, 800C and Fisher Mono Blocks 80Z, I have never checked or adjusted bias. I just put the control in the center position when cleaning insides/controls.
I have always used 16 ohm taps of various vintage tube and SS amps and newer current tube Cayin A88T. (original version, the only one with 16 ohm taps). It's bias control is internal, versions with safer external bias do not have 16 ohm taps.
5. replace their two rheostats? ('presence' and 'brilliance': copper wire-wound on ceramic body, mid/neutral position).
I have them in neutral position now, l/r frequency response equal.
do I need to keep rheostats 16 ohms? use 8 ohm rheostat with 16 ohm drivers?
sales sheet says 16 ohm, but data sheet shows range 1.0 to 5k ohms.
https://www.mouser.com/datasheet/2/303/controls_rheostats-1228697.pdf
does that mean, the drivers will draw whatever they draw (varies thru frequency range anyway), doesn't matter as long as rheostat range starts 1.0 ohm, extends past say 100.0 ohms?
https://www.mouser.com/datasheet/2/303/controls_rheostats-1228697.pdf
...........................................
thanks, Elliott
Thanks to anyone who responds with whatever answers/opinions/advice comes from this. I'm retired, covid bound, Donna is taking care of everything holiday related, too much time, always curious.
..................................
I happened across this in an old thread started by Ralph (atmasphere)
"Sixteen ohms, BTW is a very simple means for getting more resolution out of your system, as nearly every amplifier made sounds better on 16 ohms than it will on 4 or 8 ohms. Speaker cables become far less critical too."
My speakers are 16 ohms (Electrovoice horn tweeter, horn mid, 15" woofer, crossover, rheostats, from 1958).
Extremely efficient, I have more than enough power. Amp, now and in the past all had 16 ohm taps.
Of course I can hook them up to my Cayin's 8 ohm taps now and listen, but facts, opinions, advice, to learn is good.
...........................
Lots of Questions?
1. why/how do 16 ohm speakers make amps sound better, with more resolution?
2. why speaker cables less critical? perhaps this is why I/we don't hear cable differences in my system?
I'm using my homemade twisted pair of cat 5 now (8 individually insulated small diameter solid core).
3. to get exterior bias control: use 8 ohm tap for my 16 ohm speakers? (get alternate amp 4/8 no 16 tap,)
lose advantage(s)? 'sounds better'; 'more resolution'; 'speaker cables less critical'?
this says slightly more mids:
http://blog.hughes-and-kettner.com/ohm-cooking-101-understanding-amps-speakers-and-impedance/
I can fine tune my speakers via their two rheostats: 'presence' and 'brilliance', so not really an issue for me.
4. Importance of Bias Control
how important is Bias? (I don't care about heat, power output, or tube life, just as bias affects sound). Frankly, using vintage tube receiver Fisher 500C, 800C and Fisher Mono Blocks 80Z, I have never checked or adjusted bias. I just put the control in the center position when cleaning insides/controls.
I have always used 16 ohm taps of various vintage tube and SS amps and newer current tube Cayin A88T. (original version, the only one with 16 ohm taps). It's bias control is internal, versions with safer external bias do not have 16 ohm taps.
5. replace their two rheostats? ('presence' and 'brilliance': copper wire-wound on ceramic body, mid/neutral position).
I have them in neutral position now, l/r frequency response equal.
do I need to keep rheostats 16 ohms? use 8 ohm rheostat with 16 ohm drivers?
sales sheet says 16 ohm, but data sheet shows range 1.0 to 5k ohms.
https://www.mouser.com/datasheet/2/303/controls_rheostats-1228697.pdf
does that mean, the drivers will draw whatever they draw (varies thru frequency range anyway), doesn't matter as long as rheostat range starts 1.0 ohm, extends past say 100.0 ohms?
https://www.mouser.com/datasheet/2/303/controls_rheostats-1228697.pdf
...........................................
thanks, Elliott
Showing 9 responses by mijostyn
@clio09 , Hi clio, I wanted better dispersion so that everyone seated on the sofa (watching movies) would have the same frequency balance. I am sure the Sound Labs will suit that purpose. ESLs are very simple devices. I suspect if there is going to be any change in sound quality it will be in the design of the interface which in the case of the Sound Labs has been upgraded on several occasions. Like any ESL they need the right amp to sing and I know I have a pair that suit wonderfully. We shall see. |
Elliott, it is excellent that you are making your own cables. You should check out Kimber Kable. You can buy their speaker cable in rolls and terminate it yourself. I use 12TC which IMHO is the absolute best speaker cable you can buy. Also check out Canare. Great company. All my digital cables and interconnects are made with their products. Raul, I agree whole heartedly. I ran capacitors on amplifier inputs for decades. The Dalquist LP1 did that for you. You might want to try a digital bass management system such as used in the DEQX Premate. You get the advantage of time alignment which gives you much more flexibility in subwoofer placement. The best position is always on the floor against a wall or in a corner. However, this placement may not match the main speakers in time unless you can delay them to match. As an example check out my system page. Those 2001 monoliths are about to be replaced by black Sound Labs 845s. I am also working on new subwoofers. Ralph, I am about to find out :-) I already know the results will be thunderous. As for a quality goes, if they are as good as the Acoustats I will be happy. If they are better then....I guess I'll jump for joy? |
Ralph, I have seen pictures of that system with the subwoofer panels between the main speakers. It was destined to failure for several reasons. First is dipole radiators make lousy subwoofers. The wavelengths are just too long and holding the panels perfectly rigid is very difficult. Second is the set up was wrong. He was using point source subwoofers under line source main speakers. They do not radiate the same way. In order to create line source subwoofers your array has to end at boundaries (walls) at both ends and the subwoofers have to be closer than the wavelength of the highest frequency the subs are to reproduce. He would have had to have a sub panel right up against both side walls and one in the center. The beauty of this is that you sharply reduce unwanted reflective energy. Third is analog subwoofer crossovers just do not work well especially with steeper slopes. You really have to have a digital bass management system to handle the crossovers and time alignment. The best are very flexible and you can make changes while listening which is very important. But, everyone noticed that the main speakers became more transparent which is major plus of using subwoofers with ESLs. When you push the volume the sound remains perfectly organized and pain free. They just get louder. We listened to an Arctic Monkey's concert last night. Everybody had big smiles with 100 dB peaks. I cross over higher than most people as I have discovered that, at least with my system that it sounds better. I think it is easier to match things up at shorter wavelengths. But, 200 Hz is perhaps too high for dynamic subwoofers. I cross at 120 dB or so. I've never taken it up to 200 Hz. But if the set up is symmetrical It won't screw up the imaging. It might start interfering with the resolution of certain instruments like a double bass. There is nothing like the smell of napalm in the morning:-) Raul, I think the 80 Hz crossover is right for dynamic speakers when you are using one sub or a swarm system. 80 Hz is the highest you can go without disturbing the image. But, if you are using a symmetrical set up with all speakers in front of you it is fine to go higher. With an ESL like the Sound labs which is a "one way" speaker this makes a big difference but with a dynamic speaker were the woofer might only run up to 500 Hz the improvement in distortion won't be quite as noticeable although the headroom will improve. The point is that crossing higher probably won't get you much. |
When Miles wanted to be mellow he would point the trumpet down and possibly use a mute. When he wanted to let you have it he would point the trumpet right at you and fire away. It was up to the musician. It is mostly speakers that make trumpets sound harsher than normal. Raul the JC1 has been superseded y the JC1+ which is now readily available. It is very similar but even larger and costs $16K a pair which is still dirt cheep in comparison to other amps of it's quality. Ralph one thing the JC1 is not is harsh. It is one of the smoothest most effortless amps I have ever heard. Not that your MA2 is even better. The Sound Labs are certainly a match made in heaven with your MA2 given the extremely high impedance at low frequencies. I do believe this would give your amp more control/lower distortion at those frequencies. However I still believe in taking the deep bass away from ESLs. The diaphragms have a very limited Xmax. They get non linear easily creating distortion at higher frequencies never mind the doppler effect. The ESLs become even more effortless and higher sound pressure levels stay perfectly controlled and relaxed. Without subwoofers the ESLs will start sounding stressed at higher volumes. This is certainly the case with Acoustats. I can not see why it would be different with Sound Labs speakers. I will listen to them full range for a few days to see if this opinion holds. I do believe I listen at higher volumes than most people but I have discovered that with subwoofer I am quite satisfied 5 or so dB lower. Loudness compensation also helps a lot in this regard. My wife is my distortion meter. She will tolerate higher volumes with the subwoofers running:-) |
That is wonderful to hear Raul as I will be driving my Sound Labs with JC-1s at least for the time being. Dr West also highly recommends Atma-Sphere MA2's. The newer units have undergone significant changes in their interfaces. They do suffer from the same anomaly my old Acoustats had. Both designers were intent on making the speakers full range but for some reason that has to with transformer physics it is impossible to make a single transformer cover the entire audible range gracefully so both designers decided to use two transformers and a blending network to do the job. In my case I am crossing over to subwoofers somewhere around 100 Hz (125 Hz with the Acoustats) So, I do not need a transformer to go down low. Consequently I can get away with one transformer and no complicated blending network. This worked great on the Acoustats. I'll live with the SoundLabs for while before I start screwing around with transformers. Lewm relates that he bypassed the bass and brilliance controls. Dr West assures me there is no benefit in doing this. If it is easily reversible I'll give it a try. I am not fond on any additional stuff in the signal path particularly if it is not doing anything useful. |
Elliott, Lewm is correct in that you have to measure the resistance of the L pads when they are in neutral position. It may not be zero. I think it is best to do what Lewm suggested. Set them up so that they sound good to you. Then measured the resistance and substitute the appropriate resistors. Wires that run parallel to each other have the highest inductance. In other words one wire will induce a current in the next wire. Wires across each other at 90 degrees have the lowest induction. I believe the wire in cat 5 cables is parallel. Wires in a twisted pair are always approximating 90 degrees to each other and therefore have very low induction. IMHO the best wire made for loudspeakers is Kimber Kable. It uses smaller gauge wire woven in a pattern that keeps induction very low and because the wires are very close to each other parallel resistance is low. As Ralph relates you keep series resistance low by keeping the wires as short as possible. For 16 ohm speakers 18 gauge twisted pair is more than adequate. If you want to go ballistic buy a set of the higher gauge Kimber Kables. My amps are right under the speakers and I use 3 foot runs of Kimber Kable 12TC. Lewm, I finally ordered my Sound Labs!! They are a custom size, basically 845s the width of 645's, a little narrower. They will fit my situation better. Roger is supposed to be giving me an ETA today or tomorrow. You mentioned that you modified the interfaces. Did you just bypass the controls? |
Hi Elliot, The "rheostat" has nothing to do with the impedance of the speaker. It is just a potentiometer that varies the amount of power going to either the tweeter or midrange horns. 16 Ohm speakers are more efficient. Not much current is required to drive them so heavy gauge speaker wire is not necessary. But, the wire you are using probably has high inductance. You should use 18 gauge wire that is a jacketed twisted pair like this, https://www.parts-express.com/belden-6300ue-18-awg-2c-cable-plenum-rated-in-wall-speaker-wire-100-ft... Always use the 16 ohm tap. If you do not have one the 8 ohm tap will do. |