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.
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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

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thanks, Elliott











elliottbnewcombjr

Showing 6 responses by luisma31

I didn't remember you had Sound labs Lew, wow, that is something I would love to listen to, my speakers made by Duke are very good but he is / was a Sound labs dealer dealer some eons ago and he still praises the sound
For the OP, if you have some small stand mounts Elacs B6 or such, attach these in parallel with your mains and let us know what happens to resolution of the mains, I have done it with both tubes and SS and in both cases lowers resolution and increases distortion
+1 @atmasphere and
@lewm
Impedance matters on the load presented to the Amp, as Lew said there is no free lunch, the autorformers yes work if you have the problem but it is best to avoid it.As @charles1dad explained and he is very fond of low power SETs you can benefit ALOT from the 16 ohm Impedance.

Chuck's post as much as I respect and sympathize with his opinions it could be misleading, it depends on which specific experience he might have, IIRC he has Pass amps?
My own experience with several tube amps (especially SET) you would want if possible 16 ohms. Atmasphere amps are a special case have MA-1s myself and they can work with 8 / 6 ohms but 12 and 16 ohm are definitely better

Just my 2c
and used cable with plenty of conductor to do the job.
@atmasphere by plenty you mean AWG correct?


If you want to add a single resistor to replace the L pad and adjust brilliance (like Lew suggested) Mills are great, those are the ones I use on my speaker and are very transparent, 12W BTW 28 ohms in my case.
Edit: in your case of course you might want to measure the lpad setting for resistance and replace with same value, my 28 ohms is very specific to my room and driver
So I heard Raul and I don't disagree. Practically for a speaker you will need quite a few Vishays per channel which will make it more expensive and more bulkier to install but yeah if you have the money Vishays are supposed to be great and Mills good (like you said)