Help with possible Thunder 1 purchase?

adorshki

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except the stamp-frame-speaker 'flex' sound, when a Strat is pushing hard and the stamped frames bend a little allowing the speaker cones to contort and make the Strat sound rubbery!
??????
You mean the actual frame also known as the basket, the speaker cone's suspended in?

I can't see how that's possible.
There's no point at which torque could be applied to contort the basket, simply from being driven.
The cone edges themselves'd tear before they could distort metal.
In fact the whole point of the frame is to keep the components in the proper alignment with each other for accurate movement.

BUT if something's going on at the magnet, or voice coil, that I could understand.
The voice coil itself is like a reverse pickup and subject to same inductive principles.
Might be getting "locked up" at its maxed frequency or put into some kind of harmonic resonance limiting travel.
I could see that as causing the "rubbery effect".
I'm sure it's real, I just don't think it has anything to do with the basket.
And the magnet or coil couldn't exert any distorting force on the basket, either.
They're fixed to it and not attached to anything else that could provide a fulcrum for distorting force.
Can only act on the cone.
Unless the magnet's too heavy for the basket, then gravity'd be the distorting force.
 

mavuser

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sorry to be late to this thread, but since u asked I would buy a Fender amp for sure and not the Thunder-1. also for $500 i would buy many other Guild amps before the Thunder-1 (reverb or not).

Fender Blues Jr Tweed
Fender Pro Jr Tweed
Fender silverface 70s Vibro champ (or Champ)

are my suggestions.
 

Nuuska

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JBL D120 was die-cast-frame speaker - THAT I do know!

As for speaker non-linear-action - which might be GILDE's "rubbery sound" - many speakers have a"bias"-behaviour - meaning, that when driven hard they tend to push the voicecoil-cone-assembly outward or inward - wiring polarity does not play any part on this - thus misaligning it from center position - therefore introducing asymmetrical distortion behaviour - while voice-coil vs top-plate ( magnetic cap ) alignment was not symmetrically in the center position.

Personally - I do know nuthing about it - them big boys have talked about it - I might have heard or read something long ago . . .

Google is your friend etc.
 
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gilded

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Look guys, I'm not an engineer. I do know a lot of good guitar players and one of them A/B'd his Super Reverb with my Pro/JBL rig one fine Texas day about 10 years ago. He could get 'The Rubbery Sound' with the Super Reverb/CTS alnico magnet stamped-speaker amp but not the Pro/JBL amp.

I asked him why he could get all the other sounds with the Pro but not The Rubbery Sound and he said it was because the JBLs were caste-frame speakers and the the CTS (Chicago Telephone Supply) speakers were less-rigid, stamped-frame speaks, could make it happen.

I wouldn't know if he was right or wrong about what the amp was actually doing to allow him play like that, but that was his belief, his explanation of what was going on. He heard other players make that sound, knew he could duplicate it, did it and went on to other amps in the... Relentless Search For Tone.

I'll tell you what. I'll ask him if he remembers and come back with more Veer if he does.

gilded
 

Nuuska

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Hello

The JBL cast frame is not the reason - but JBL has 4 inch voice-coil with about 150W continuous power handling - and Jensen speakers are more like 30W - therefore with JBL:s there's less compression and other cone-stress related things when driven hard.

To put it short - for clean use JBL - for dirty use Jensen or Eminence or Utah or any other small power speaker.
 

adorshki

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I wouldn't know if he was right or wrong about what the amp was actually doing to allow him play like that, but that was his belief, his explanation of what was going on. He heard other players make that sound, knew he could duplicate it, did it and went on to other amps in the... Relentless Search For Tone.
Understood, I just think he's been "misinformed".
And no disrespect intended, I just suspect it's one of those myths that keep getting new leases on life, but I'm still willing to allow that maybe there's something I'm missing.
But Nuuska's got a lot better handle on this stuff than I do, and seems to confirm my reasoning that what's really happening is happening at the magnet and voice coil, not the "basket".
Especially in light of his observation about "bias" as in how a speaker will tend to distort when getting near its spec limits: "when driven hard they tend to push the voicecoil-cone-assembly outward or inward - thus misaligning it from center position "
This is also why bigger magnets mean better speakers in a very consistently reliable relationship, all other things (voice coil, speaker material, size) being equal.
That's likely also why the JBL will run cleaner as Nuuska mentions, but I suspect there IS a point at which it could be induced to exhibit the same behavior, it just wasn't being driven hard enough. And likely intentionally designed to reduce the chances of it happening.
I'm coming from the audiophile school and citing one of the reasons original AR speakers are so much more highly valued than the modern replacements, for example: all the modern stuff has really wimpy magnets.
I'll tell you what. I'll ask him if he remembers and come back with more Veer if he does.
gilded
No worries, don't mean to stick you in the middle but if it's a subject of genuine interest to you, then absolutely veer away!
:smile:
 
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gilded

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No worries, don't mean to stick you in the middle but if it's a subject of genuine interest to you, then absolutely veer away!
:smile:
Talked to my friend. He remembered the shoot-out and said that it was a Strat and a BF Super Rev.

He said if there were any pedals, they were inline, but not activated. The amp volume was at 4 or 5, the treble at 7, bass at 4. I'm sure the mid control was on, but he didn't give a number. The vibrato would not have been on.

I asked him what made it all work and mentioned the cast-speaker vs stamped-frame recollection. He had no specific reply, but did opine that the Super and it's speakers were working harder than the JBLs and that's what made the difference. He said that he has always liked the sound he could get with one speaker humming away, rather than 4 speakers loafing.

This guy plays with a very soft pic and his amps are always set to 'Warp Nine.' That may be part of the equation, too.

That's all the veer I have left in me, Al. See you round Campus.

gilded
 

matsickma

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My first amp was a black 1965 Thunder 1 RTV. I was totally shocked when I played other amps with reverb and the reverb came out of all the speakers?!

The T1 RVT is a pretty unique amp employind two different power amp sections. The main amp drives the 12 speaker and had 15 to 20 W. The output of the clean 12 speaker is tapped off, attenuate and then fed back into the reverb tank into the 2nd lower power amp section if about 6 which then drive the small reverb speaker.
The RTV amp allows you to get a lot of different sound options. The amp has 3 inputs with different filtering and attenuation. The tone controls also have a Bright on Pull circuit. So you csn get a lot of different tone options out of the Guild RTV amps. I presently have a black '65 model with a 12 inch JBL K120 speaker and stock CTS reverb speaker. I also have a stock '67 beige RTV model. Its a nice warm tone amp with a sound not easily found in other amps. Great reverb and Tremelo.
Good for studio and small venues.
I perfet the RTV model over the Thunder 1 non reverb model.
RTV's usually sell in the $350 to $450 range.
M
 

Nuuska

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Hello

Then there is one more aspect that makes difference when driving amp near full tilt.

Does it have tube- or solid state rectifier? Tube rectifier is acting a bit like compressor at full power. I do not play like that personally, so other people can explain that better.
 

gilded

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An old Super Reverb would have a GZ34 rectifier, same as the AC30s that I am familiar with.
 

gilded

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matsickma,

Any difference between how the beige and the black RTVs sound? I've never heard a black one and wonder if the 2 amps might be slightly different in construction. Or maybe not, that's why I'm asking you!!
 

matsickma

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Hey Gilded,
In general I would say no difference in tone or charactericts. Granted I didn't swap things around to make all things equivalent. I have owned many of these amps over the past 20 years. I have never checked to see if the main circuits and components are identical in value and manufacturer. But my ears, when young and old, seemed similar. Naturally the 12" speaker model, type and manufacturer will have a major impact to total sound.
However I still clame they are essentially equal in sound attributes.

Not sure why Guild redesigned the chassis on the Thunder1 but it is a better structure. The difference between the black and beige models is a little different cabinet size and shape and more importantly the black RTV cab is particle board where the chassis of the beige amp is pine. The beige amp also has a AC power phase reversal switch.
All of us geasers remember the two prong AC power chords without polarity plugs and the electrical shocks when touching a MIC or another musician. So Guild added a switch to make phase allignment easier with the beige RTV.
Naturally the front grill cloth was changed. Typically the black RTV front silver "fish scale" cloth looks dull and faded, However when new they were beautiful bright shinny silver. I once had a black Thunder 1 with stock cover and its grill was like new, beautiful.

M
 

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Hello

Then there is one more aspect that makes difference when driving amp near full tilt.

Does it have tube- or solid state rectifier? Tube rectifier is acting a bit like compressor at full power. I do not play like that personally, so other people can explain that better.
It has a 6ca7 rectifier, iirc. That is much more like a gz34 than a 5y3.also, the filtering is double that of a Princeton, so there will be less sag.
 
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Guild redesigned the amp because it simply wasn't roadworthy.
 

adorshki

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He had no specific reply, but did opine that the Super and it's speakers were working harder than the JBLs and that's what made the difference.He said that he has always liked the sound he could get with one speaker humming away, rather than 4 speakers loafing.

gilded
Sounds like a confirmation of what Nuuska and I were suspecting, that it was how the speaker was being driven and not some sort of distortion caused by the basket.
"Carry on!"
:smile:
 

gilded

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Sounds like a confirmation of what Nuuska and I were suspecting, that it was how the speaker was being driven and not some sort of distortion caused by the basket.
:smile:
I dunno about that, amigo. If the whole amp is jumping and shaking, I could see the speakers joining in the fun!

Remember, no degree, might as well be a Flat Earther!
 

adorshki

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I dunno about that, amigo. If the whole amp is jumping and shaking, I could see the speakers joining in the fun!
What, you haven't heard of bolting 'em down yet?
:glee:
 
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gilded

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Re the 'Rubbery Sound' and the search for Why?

I talked to another friend, a credentialed Electrical Engineer who builds Marshall, Tweed and Black-Face Fender amps for fun. He listened to my botched and bungled postulation of the caste-frame vs stamped-frame theory, then threw in a different wrinkle for our Collection of Great Minds to consider:

The vintage-spec 4x10" Speaker Baffle Board!


First, he politely discredited my speaker frame theory. He said, "Grab a stamped-frame speaker and see if you can bend it with your hands." [We both agreed that I wouldn't be able to do any bending]

He then said, "Look, early Fender amps had relatively thin laminate-wood baffles. The Fender 4x10" combos like the Tweed Bassman and the Brown-Face Concert have those baffles and the combination of a relatively flimsy board and 4 speakers move around a lot more than the same baffle with one or two 10", 12" or 15" speakers of the same thickness."

"As well, when the four speakers get going, lots of interesting resonances are happening while that baffle board is moving all over the place." [which in turn allows guitar players to make some interesting sounds]

I asked about him about the voice coil contorting and he said, 'Lots of things are happening; maybe the voice coil, maybe cone cry, but a lot of it is the relatively thin, 4x10" baffle boards, jumping all over the place."

I then said, 'So it's the voice coil and cone cry together?'

His Reply? 'No, that's not all of it.' Then he gave me an example:

"Suppose you and I are holding on to different ends of a string that is stretched out between us. You keep your end fixed in place and I move/shake/jump-rope my end of the string around. You'll be able to see the movement of the string, right?" [I agreed]

"Okay, now let's suppose that we are both moving our respective ends of the string around at the same time. You'll be able to see that the string is moving around a whole heck of a lot more, yes? [I agreed, again]

That's what happens, when you have the, uh, 'correctly thin' speaker board! The speakers move, the baffle board moves, everything moves and it changes the sound.

Finally, he said, "It's not just the thin wooden laminate speaker boards, the 4x10", Super Reverbs have particle board baffles and Super Reverbs can do it, too." He also worked on a fairly new 4x10" Fender DeVille amp recently and he could hear some of the same characteristics.

Whew, I think I got most of that stuff right!

gilded
 

Nuuska

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Sorry to shoot a good story down.

Wavelength of 1kHz is roughly 12 inches - half wave, that is required for full cancellation is 6 inches - 1 inch for 6kHz - 1/2 inch for 12kHz

12kHz is up there in harmonics area - like 24kHz = 1/8 inches.

Just try pushing the cabin front panel to see what kind of force it takes to move it 1/8 inches.

But the cabin resonating because of it's measurements & materials does influence the sound at all levels.

Dried-out glue joints rattling can easily produce extra noise. Emphasis on NOISE !!!

Your friend may sincerely believe, that what he hears comes from front-baffle flexing - let's let him . . .


Voice-coil compression and non-linearity together with cone not being perfectly stiff and therefore bending and flexing are definitely true causes for sound change at near-limit power.

Also a tube amp near it's full power is far from linear.


Search goes on . . .
 
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