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 4 responses by tomic601

Ralph - the Wagner you cite, what is your reference LP for that ?
best to you in the new year ?

jim

Interesting thread with a lot to unpack if learning is the goal. Some astute gems :-) and yes, I have much to learn...

I find it best to approach the amplifier/speaker wire / speaker as a system. It is an unfair advantage as Richard Vandersteen says when you engineer a relatively easy load and then purpose design both the amp and wires for that load.  He has Tubes and SS in the M7, SS only in the M5, post Covid stop by, I assure the M7 is anything but bright. To repeat its a system. I believe JA said it was one of the best amplifiers he has measured. Of course he listened to it as a system w model 7 speakers.


 I spent a career at one of the most advanced technology companies on or above the planet, many many issues and failures due to cross disciplinary ( speakers and amps in this thread ) lack of system engineering principles being adhered to....

go to all that work to build an OTL to hook it up to transformers, two of them per side... for the OTL fans ( count me in ) this is a head scratcher.... there are of course some brilliant transformer designers:

Modjeski and whoever did the Mac240.. of course enough voltage in the tube amp and you can direct drive the ESL.

on feedback, it ain’t free - introduces other distortion you may or may not like. Many threads are just one flavor of distortion against another... might as well watch cat chase tail... real movement forward will seek to banish distortion period. 
Horns and horn miking and horn microphone choice are imo a black art.... assuming artistry, the tough choice is picking the right microphone.... and w horn dynamics that is a daunting task ( see again the part about distortion )

back to Elliott, who is a cool dude, your MX-110z can drive a long RCA , I would go that route, shorten up the speaker wires, then listen, solve for R ( measure L pad ) and replace w fixed value and enjoy !!!!!

you can see a variety of speakers and amps and a 30’ run of BJC rca in my vintage system picture, horns, planers, dynamic, SS, Tubes, analog, digital, tape we do it all !!!!!!!!

jim




one time at bandcamp our speaker designer became an amplifier expert...not !

my $ is on Ralph

of course, it’s an unfair advantage when the amplifier is designed for the load and the load is designed to be relatively easy....by the same mindful designer.... Vandersteen M7 or M5, there are of course other designers doing both, MBL, ATC, etc...

i believe there is an exception, keeping the amp in class A by light loading..ala Roger Modjeski