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
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




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

jim

Dear @charles1dad  : Unfortunatelly wrong all your assumptions on me and the Agoners that I  can see I know it them better than you and no not many of them have several first hand experiences listening LIVE MUSIC at near field position in a Music Hall just behind the Orchestra Director listening the Fantastique or 1812 or the like, of course that tehre are several Agoners way superior on that kind of experience than me.
Or seated at 1m. from a drum set listening, at true real SPL, those Zildjan cimbals. 

I never talk or post something I'm not totally sure of it.

I'm not insulting any one but facts are facts and only for your records I was a tube lover electronics for at least 10 years and heard almost any tubes from Jolida to the Audio Note ke-gon passing for Atmasphere, Allnic, Audio Research, Conrad Johnson,  BAT, Cary, Wavac, VTL, Marantz, Luxman, etc, etc. Finally I learned. I'm sure you will too in the near future or maybe you already learned all what any music lover/audiophile must learns. If this is the case good for you.

Anyway, appreciated but wrong. No, it's not because tubes vs SS, the overall issue is a lot more complex that only that.


R.

Hi Raul,
I don’t question your experiences and the subsequent choices you’ve made as a result. You have extensive exposure to many fine tube components. I’ve extensive exposure to a variety of highly regarded transistor components. For your needs/objectives you have determined that solid state is the superior option. I ultimately was more persuaded by tubes. As dictated by our respective experiences we’ve chosen different paths to follow. That’s no problem at all. I respect your input on this forum.
Charles
tomic601

thanks for ’cool dude’, I think more like ’old dude’ many must think ’long winded’.

I ordered everything for new DIY Speaker Cables

COST: $136.44 incl tax & delivery
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CONNECTORS (spades and adapters at speaker’s back panel)

spades, pure copper 2 set screws 8 pcs

https://www.wish.com/product/5f20285d021ca40450e0db12?from_ad=goog_shopping&_display_country_code=US&_force_currency_code=USD&pid=googleadwords_int&c=%7BcampaignId%7D&ad_cid=5f20285d021ca40450e0db12&ad_cc=US&ad_lang=EN&ad_curr=USD&ad_price=25.99&campaign_id=7203534630&gclid=CjwKCAiAirb_BRBNEiwALHlnDzHJI5sHBGgV6SU4SPObQJRDpIRlNlS-YE4jEMoNNitRfQDti9QnlhoCrSoQAvD_BwE&share=web

5 way binding post, pure copper fits 3/4" thick panel

https://www.wish.com/transaction/5fedeb5a8db692f0c1f84c07/product/5f4a22dd64ef860043939722/5f4a22dd64ef860043939723
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CABLE:

I ended up ordering a cat8 s/ftp (shielded, foiled twisted pairs)

When you twist them you lose length, I need 12 ft straight x 2 = 24’ x 2 spkrs = 48lf straight, a roll of 50ft would be short.

Speaker cables l/r should always be the same length (time of travel aligned, hah!).

I chose this cable, ordered 10 m (33ft) red; 10m (33ft) black, each leg 16lf to make 12 ft: red/black twisted.

https://www.ebay.com/itm/174307181712

22 awg, 8 solid (not stranded) OFC copper S/FTP construction = 13 awg

This chart shows relative gauges, physical sizes, and resistance.

https://www.rapidtables.com/calc/wire/wire-gauge-chart.html

two basic choices cat gauges: largest 22 awg; smallest 26 awg

22 awg x 8 = 13 awg (+152% area above 26

26 awg x 8 = 17 awg (+152% resistance above 22

22 awg solid = less flexible is not an issue for me.


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CONDUCTIVITY CHART

https://www.bluesea.com/resources/108/Electrical_Conductivity_of_Materials

silver is only a little more conductive than copper

gold and aluminum are only a little less conductive than copper

brass is a lot less conductive than copper

COPPER TYPES (hard to verify true facts)

often text says solid but diagram shows stranded; text says 23 awg, chart shows 26 awg, and seller’s answers are often not clear.

https://www.thomasnet.com/articles/metals-metal-products/types-of-copper-wire/

’Pure Copper’, (99.9% pure) often in text, with or without OFC

is not in the above article, it is in this article,

https://en.wikipedia.org/wiki/Oxygen-free_copper

C11000 - also known as Electrolytic-Tough-Pitch (ETP). This is the most common copper. It is universal for electrical applications. ETP has a minimum conductivity rating of 100% IACS and is required to be 99.9% pure. It has 0.02% to 0.04% oxygen content (typical).

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L PADS

will be disconnected, new + wire direct from crossover for both horns
(one as a test first)

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WOOFERS, remove, check cones

Picking these suckers up onto a low bench for the work is a job for two masked men. Recent MRI: I now have 4 herniated discs, one tear, pinched nerve.