Tell me how to check ohm of speaker

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100 watt amp? (2) 50 watt speakers?

One more question, this is a 100 watt amp. Now that I know I need (2) 8 ohm speakers in parrallel. Do I buy (2) 50 watt speakers or would you recommend 75 watt or 100 watt speakers?????
 
Well, two 50 watters would do. But I've always been one to have a safety margin and besides, I don't think 75 watters would be that much more expensive than 50 watters. Really, it kinda depends on how loud you think you might be playing and how much do you want the speaker to break up. You said a Plush amp right? Isn't that a solid state amp? If so you might want to go with 50 W. rated speakers so they'll distort a little more. If you want clean..go with higher ratings. The brand of speaker makes a tremendous difference in sound. Almost like picking different instruments for their tone. Celestions of course are prized for their guitar tone and I've always been partial to the old Altecs. But it's a matter of taste and I don't think you can really say any one brand is best. If money is limited, lol, then probably some Emminence or whatever you can afford would do fine. Let me know what you get and how it works. :)
 
Hey Lt. Bob, My Plush amp is a '71 or 72 model super 450. It has (4) 6L6's (3) 12ax7's and (1) 12au7 for the reverb. The tubes are not matched as I think who ever had this amp before just put in whatever they could find. That's one of my problems though. I can find no info on this amp. Some say I should use a 12at7 for the reverb, I don't know. As far as the speakers I was looking at the Emminence Legend GB 128, 50 watt, suppose to have that 70's brittish sound. I haven't made the final decision though. Another problem I have is I can only turn this amp up to about Vol. 4 and it's LOUD. Someone said that since the tubes aren't matched, that the bias is probably not even close to set like it should be. I don't know if that's true or not, or if that has anything to do with the Vol. maybe it does???? Oh, and about Sunny Florida. It's just now April and it's in the mid 80's already. Sometimes I'm ready to get the heck out of here. It gets hot, and when you work in air conditioning all day and get off from work the only thing I want to do is get to the house back in the A/C. I'd like to find a place where the temp was 78 all year round. NO heating bills and no a/c bills.
 
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Wow, cool amp. A friend of mine is a major collector and he would lust for that amp. The bias wouldn't affect the loudness much. With 4-6L6's it's gonna be loud. That would in fact be about a 100 watt amp, even a little more. Tubes work best if they are matched but it's not an absolute neccessity as long as the tubes are OK. You could search the net and I'm sure you'll find a site that will tell you about Plush amps and their tubes. I might even look when I have a chance. You've got my curiosity up. If you find a site, it'll probably even tell you about biasing. Some people re-bias after every tube change. If the volume gets too loud too fast, you could try changing the volume pot to one with a different taper, but I don't think I would bother, just learn to use it as is.
My wife has elderly parents in Sarasota so in the next few years we will probably move there to take care of them. I'm a piano tuner and they're getting scarce so I can work anywhere. I'm also a good saxophonist and I have no doubt I can find work on that too. As for the heat, I live in Louisiana so I'm used to it. The mosquitos too. :D
 
Flash,

You can easily estimate the nominal impedence by measuring the resistance.

Impedence is the sum of both resistance and reactance. Resistance is static, and reactance depends on things like frequency and such. The nominal impedence of a speaker is usually about 25% higher than it's DC resistance.

To estimate the load on your amp disconnect the speaker plug from the amp but leave the speakers wired as they are. Set your Ohmmeter to its lowest range. Measure the resistance across the hot and ground ends of the speaker plug. Multiply that value by 1.25 then round it off to the nearest 2,4,8 or 16 Ohms.

Lt. Bob mentioned that it would be safe to use either a 4 Ohm or 8 ohm load on your amp. This probably true, but there is another consideration besides safety, and that's efficiency. Tube amps use output transformers designed for specific loads. If you don't use the right load your not getting the optimal amount of power from your amp. In some cases, using the "wrong" load might have a desirable sound. But this requires experimentation, and for sure the amp won't play as loud it would with the "right" load.

barefoot
 
I've only found one place on the net that mentioned a plush model super 450 and that was from a place that rents equip. I e-mailed him to ask and I got a response from a friend of his that was watching the store for him. He said the guy went out of town and was going to be gone for awhile. I have never heard back from him and now when I do a searce I can no longer find the web site. That's why I was hoping someone on this forum might know someone who has one. Or maybe a suggestion as to where I might post a message. I tried one other place I believed was called guitaramp forum, But got no responses from there yet.
 
Hey Flash, I know a couple of folks that are into vintage stuff in a major way. Let me ask around and I may be able to help you find out about the tubes. Barefoot is right..tube amps have a particular load in mind and in some old amps, you will even see multiple taps off the transformer that match to different loads. He's right about the safety aspect, you won't hurt your amp but not only might it not put out full volume into the wrong load, but it can have higher distortion and it can even affect the frequency response of the amp which you would hear as a difference in tone. Don't get TOO caught up in all this, you can drive yourself crazy and the final thing that matters is if it ends up sounding the way you want, BUT if we can figure out what load it should have, that would be best. It might be a few days before I can track down my bud, we're not playing 'till this weekend and he's hard to find at other times but when I find out something, I'll let you know. :)
 
I've got some Aspen-Pitman books at home and I'll look tonite to see if the schematic is in there. If I can find any info for you, I'll post it here. If not, good luck to you.:D
 
If we all strike out here, I did find a link for a fella named Andy Brauer who has one of these amps. About half way down the page there's a link to email him. Maybe he'd be willing to help you out. It might be worth a try? I'll still check my books when I get home.

http://members.ebay.com/aboutme/andybrauer.com/
 
Lt. Bob and Monte, thanks a lot. That's so cool. Monte, That Andy Brauer is the guy I was talking about that has the equip. for rent. I couldn't remember his name and I couldn't find it again on the net. My computer crashed a while back and I lost all my E-mail stuff along with every thing else.... Thanks, let me know if you find anything out. Thanks again
 
Flash,
Just got home and checked the Aspen-Pitman books and got zip. I was thinking though...From what I've found on the net this amp is rare, desireable, and collectible. You might want to consider having the original speakers reconed to maintain the amps authenticity and sound (although recones will probably sound slightly different than original). I think the amp will be worth more if you ever decide to sell it. If you can email me any numbers that you find on the speakers or possibly even some digital pics, I can tell you approximately what the cost will be to recone them. And, I would be happy to do it for you. (This is not an ad- I've got plenty to do already!)I will also say that even if you replace the speakers, be sure to save the originals. If you do sell the amp, the buyer may want them. At the very least, I could build recone kits for them using generic parts. Another point that should be made is...depending on what's wrong with the speakers (paper torn, voice coils open, etc. etc.)I might be able to repair them rather than fully recone them and save you some cash.

Just some more options to consider,
Monte
 
Monty, I've kinda been thinking the same thing. I'm really starting to wonder how many of these things they made. As far as #'s on the speakers I seen a same piece of yellow parer on them. I don't know if it had anything on it or not. I will be real careful and see what I find out. I'll let you know. So you recone speakers? What if these things are really strange? Or are speakers basically the same? Just off the top of your head, what would we be talkin' if the papers just torn? Would you have any idea what it cost to ship from florida? I would have to consider all this. I do like the idea though....... Talk to ya soon...
 
Flash,

I hate to start mentioning numbers at this point untill I know what we're dealing with here. If you can email me some more info like I said above, I can give you exact quotes incl. shipping. Even if you decide not to have me do the job (which won't bother me in the least), you'll have an idea of what a local recone center might charge you to do the gig. Possibly there's some one closer to you that you'd rather deal with. Either way, I merely wanted to make you aware of these options.

In answer to your other questions...Yes I recone speakers... In very simplistic terms all speakers are the same in that they have a cone, voice coil, spider, etc. with the exception of piezzo electrics, ribbon speakers, servo-drivers, and other strange "freaks of nature".
 
Yeah Flash, Monte's right about that amp. Definately a collectable. I'm curious. What color is the tuck and roll covering? That is what it is covered in isn't it?
 
The color is pure black. It's amazing, I know I've posted mess. on about 4 forums. No one knows to much about this amp. except that they remember seeing one in the early 70's. I can't wait to find out more.
 
I actually played on one when they came out. A friend loaned it to me for a gig but I don't really remember much about it. At the time I was in love with the roll pleated Kustoms ( shows how much I knew) :) and considered it ugly. Now I'd love to have one and you seem to have the last one on earth. It's probably worth some bucks. Congratulation. Let us all know how it works.
 
Hey Flash, good news. My partner in the play for profit business that I told you about, (the collector) has a Plush. He said I can have it for a while if I want so I'll get it next week and we can look thru it to see whatever you need to know. Maybe I won't give it back. He said it's ungodly loud. :)
 
If it's the same one I have, he's right. I turn this thing on 3 maybe four, at five it blows you out of the room.
 
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