Sound City 4-12 w/9.4 Ohm Speakers

20 Studio, 50+, 50PA, 50R, L100, B100, L120, L120PA, L120R, 120 SLAVE, B120, B150, L150, L200, B200, Concord, and SMF

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby Sludge on Fri Jun 26, 2015 2:18 am

I played the Sound City as an 8 ohm cab last night for a few minutes. I was using an L.P. Custom through a non-master 100 watter and kept the volume at 9 o'clock and the tone at 12. The cab was solid, and sounded mighty fine with all pickup selections. I'm looking forward to playing it louder, but need to put some distance between it and me. I'm hoping its age doesn't show too badly as the volume increases. The aluminum dust caps didn't sound as bright as I feared. Maybe because they're center ported. If they prove feral while recording I'll try taming them with moongels, felt, tape, etc..

Thanks for helping. If anyone has anything to add I'd be glad for it. I'm anxious to learn more about speakers that measure 9.4 ohms, Fane, aluminum domes, Sound City cabs, etc. Don't be afraid to wake the dead. This home school music thing is nearly everything to a moldy, wall banging, shut-in like myself.
Sludge
Peasant
 
Posts: 15
Joined: Wed Jan 01, 2014 12:17 am
Location: There's no place like home.

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby robkhooster on Tue Jun 30, 2015 8:34 pm

Pretty much the same drivers and cab that I've got. Sound awesome don't they? I only run a nominally rated 60 watter through mine as I do worry about burning them out with my 100 watt amp, and it only comes out for special occasions as it's kind of heavy...

Image
robkhooster
Court Jester
 
Posts: 83
Joined: Mon Oct 14, 2013 11:26 am

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby robkhooster on Tue Jun 30, 2015 8:45 pm

Papa Dog is the one to ask regarding SC stuff btw.
robkhooster
Court Jester
 
Posts: 83
Joined: Mon Oct 14, 2013 11:26 am

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby pdf64 on Wed Jul 01, 2015 6:10 pm

What resistance do they measure?
My band:-http://www.youtube.com/user/RedwingBand
pdf64
Knight
 
Posts: 1243
Joined: Thu Dec 14, 2006 9:55 am
Location: Staffordshire UK

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby robkhooster on Wed Jul 01, 2015 8:51 pm

Just measured the cab as a whole - 10.7 ohm dc resistance. Never unsoldered the drivers so not measured them individually. The new V30 loaded 2x12 that I normally use measures at 7.5 ohm with the same meter.
Last edited by robkhooster on Wed Jul 01, 2015 8:56 pm, edited 1 time in total.
robkhooster
Court Jester
 
Posts: 83
Joined: Mon Oct 14, 2013 11:26 am

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby robkhooster on Wed Jul 01, 2015 8:54 pm

I've used it in the rehearsal room like this for a few hours at a time with the amp set to 7.5 ohm at decent volumes without any ill effects.
robkhooster
Court Jester
 
Posts: 83
Joined: Mon Oct 14, 2013 11:26 am

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby Sludge on Wed Jul 01, 2015 11:07 pm

Thanks much for posting. I really appreciate it. That's interesting info. and good to hear. I'm glad you haven't had problems. Is it an all valve amp? I'm wondering if a tech could accurately measure the impedance of my cab.

Is there a way to add pictures without outside hosting?
Sludge
Peasant
 
Posts: 15
Joined: Wed Jan 01, 2014 12:17 am
Location: There's no place like home.

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby pdf64 on Thu Jul 02, 2015 8:39 am

I'm wondering if a tech could accurately measure the impedance of my cab

That should be simple, eg run a signal generator at about 10Vac with a 1k resistor in series, over say 200Hz - 500Hz.
With the speaker out of the cab or with the back off the cab.
That should avoid any resonances and so the (potentially divided) voltage across the cab give a true reading, provided that a true rms meter is used.
From that voltage the cab's impedance can be derived, eg 8 ohms would have 79mV across it.
My band:-http://www.youtube.com/user/RedwingBand
pdf64
Knight
 
Posts: 1243
Joined: Thu Dec 14, 2006 9:55 am
Location: Staffordshire UK

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby robkhooster on Thu Jul 02, 2015 10:04 am

Yes it's an all valve amp (I would get lynched on here otherwise) ;-)
robkhooster
Court Jester
 
Posts: 83
Joined: Mon Oct 14, 2013 11:26 am

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby Sludge on Thu Jul 02, 2015 3:17 pm

Do your speakers have an ink stamp on the frame by the spades that states "Hi Fi 8". Mine do, as pictured earlier, and it has me wondering what that's all about.

What power rating is on your frames? I used a magnifying glass but couldn't get a read.
Sludge
Peasant
 
Posts: 15
Joined: Wed Jan 01, 2014 12:17 am
Location: There's no place like home.

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby Sludge on Thu Jul 02, 2015 4:09 pm

Thanks for the info pdf64. The back of my cab is sealed. Would it be best to wire all four speakers together out of the cab, or just measure one? I need tech-work and might get this done soon. I'll talk to the tech about it.
Sludge
Peasant
 
Posts: 15
Joined: Wed Jan 01, 2014 12:17 am
Location: There's no place like home.

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby robkhooster on Thu Jul 02, 2015 4:32 pm

Mine are rated at 40w each, but I wouldn't want to exceed more than half of that these days given their age and rarity. Looking closely at the pics again - the frames on mine do appear to be slightly different to yours as the connecting terminals are in a different place; mine are on the back of one of the arms of the frame, yours are in between; and the design of the frame itself looks slightly different too. So I suspect mine are slightly older, no idea why they have been given the same model code though. I don't recall any hifi 8 stamps either. Got a pic of the whole cab, especially the model plate on the back if it's got one?
robkhooster
Court Jester
 
Posts: 83
Joined: Mon Oct 14, 2013 11:26 am

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby pdf64 on Thu Jul 02, 2015 9:45 pm

Yes, the Sound City labelled ones look to have the cast aluminium type frame, whereas the Dallas Arbiter looks to be pressed steel.
But the rating labels and readings indicate that the magnet and voice coils are the same.

I don't see the benefit of testing all 4 speaker's impedance; 1, or maybe 2, tested when removed from the cab.
My band:-http://www.youtube.com/user/RedwingBand
pdf64
Knight
 
Posts: 1243
Joined: Thu Dec 14, 2006 9:55 am
Location: Staffordshire UK

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby PeterS on Thu Jul 02, 2015 11:10 pm

If they prove feral while recording I'll try taming them with moongels, felt, tape, etc..


Feral! :lol: I've successfully removed them with lacquer thinner, but I'm not sure I would try that with high-value speakers...
PeterS
King
 
Posts: 6156
Joined: Tue Sep 13, 2005 4:07 pm
Location: Canada

Re: Sound City 4-12 w/9.4 Ohm Speakers

Postby Sludge on Thu Jul 02, 2015 11:40 pm

Thanks for the info. That's good to know. I recently saw a video lesson for replacing domes, and a razor was used to cut the aluminum dome off just above the glue. Maybe use the razor first, then put a rag in there to catch solvent and debris. In the vid they just glued a replacement cap on without complete removal. I was surprised to see him going at it with a razor.

I'm all for the preservation of historic objects. But ultimately, I might be thought of as some nameless defiler who marred and wasted a few things in my feeble attempts at making art, by the few who stumble across my trail of mistakes.

I'll get pictures of the cab posted soon. That's why I was asking about posting pictures minus otherworldly hosting.
Sludge
Peasant
 
Posts: 15
Joined: Wed Jan 01, 2014 12:17 am
Location: There's no place like home.

PreviousNext

Return to Sound City

Who is online

Users browsing this forum: No registered users and 1 guest