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Hoffman Amps Forum image Author Topic: So, 2deaf, speaker attenuators  (Read 17620 times)

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Offline jojokeo

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Re: So, 2deaf, speaker attenuators
« Reply #50 on: November 12, 2014, 03:21:45 pm »
Quote
Maybe one of you very knowledgeable guys could elaborate on why this would feel different than a VVR/Power Scaling?

While you're waiting for one of the very knowledgible guys (they really are) to reply, maybe you could consider that a VVR reduces the power to the preamp and output tubes and the light bulb only reduces the power to the output tubes.

Quote
Just so happens the topic is not "how to get full output and not stub your toe".

I didn't know that being snide was acceptable on this forum.
No, we've built many amps just power scaling the power tube(s) or pi and power tubes only leaving the preamp alone.
 
Being snide, snarky, sarcastic, impertinent, cutting, critical, kidding, teasing, etc. are all okay as long as it's meant in a good natured way.
To steal ideas from one person is plagiarism. To steal from many is research.

Offline Willabe

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Re: So, 2deaf, speaker attenuators
« Reply #51 on: November 12, 2014, 05:12:23 pm »
a VVR reduces the power to the preamp and output tubes and the light bulb only reduces the power to the output tubes.

You can wire up the VVR/Power Scaling so it only reduces the B+ for the power tubes. You don't have to us it for the whole B+ rail.


               Brad     :icon_biggrin:

Offline Willabe

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Re: So, 2deaf, speaker attenuators
« Reply #52 on: November 12, 2014, 05:14:51 pm »
I have a soundproof amp room.  Soundproof!  I control my volume by how far I open the door, but this presents a problem.  In a small to medium size room while playing live, I just cannot seem to carry it with me.

Just get a trailer and pull to gigs with you.


                 Brad     :laugh:

Offline 2deaf

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Re: So, 2deaf, speaker attenuators
« Reply #53 on: November 12, 2014, 06:48:45 pm »
Quote
But still - the mini mass had the most treble loss of all my attenuators which had to have bypass caps put across the rheostat (see earlier photo) and they worked well like when we put a treble cap across a simple vol control. The sizes of those were much larger than what we use.

I'm seeing a couple of serious power resistors and a real meaty rheostat, so a whole bunch of the signal is probably being handled by them.  This would make this attenuator act more like the Power Soak.  I would think that he would have to have a few motors in there to make a decent attenuator.

Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #54 on: November 12, 2014, 09:01:34 pm »
I'm tellin' ya - kinked toaster elements.  The secret to the universe.  The holy grail.  The big banana.  The rare combination of asbestos, resistance, reactance, and hot gig snacks.

Seriously, we are talking about bringing a roaring beast down to a moderately annoying beast.  Any one of the previously discussed gizmos will do that.  The problems occur when we try to bring a roaring beast down to a whimpering shadow of it's former self.  I never did that with the Altair and it was the most transparent gizmo I've used to cut sound pressure in half.

I've decided not to believe a thing you guys are telling me. I don't care if you are one of the "very knowledgeable guys" or not.  I am happy in my self imposed sandwich making bliss. :think1:

Jim the snidemeister :icon_biggrin:

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Offline jojokeo

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Re: So, 2deaf, speaker attenuators
« Reply #55 on: November 12, 2014, 09:50:13 pm »
I'm seeing a couple of serious power resistors and a real meaty rheostat, so a whole bunch of the signal is probably being handled by them.  This would make this attenuator act more like the Power Soak.  I would think that he would have to have a few motors in there to make a decent attenuator.
4 total power resistors, 1 50w 50r rheostat, and one un-rated wattage and unknown resistance speaker motor. The signal enters to the bypass switch then to the rheostat's #1 leg. The mid/wiper of rheostat goes back to the bypass switch and to the output jack. The speaker motor also goes (paralleled) to #1 and #2 legs of rheostat directly. The bright caps/switch also goes to pins #1 & #2 of rheostat. The 4 power resistors go to the SPDT on/off/on impedance switch.  It appears that their only involvement is if you choose either 4 or 16 ohm settings. In the middle off position they do not make contact and the 8ohm wire goes right to the rheostat. So, the rheostat and speaker motor are "active" during all settings, the power resistors only when not in 8ohm setting. Everyone can draw their own schematic now :)

All you need is my headphone amp's stuff and it's the same thing basically just not adjustable for impedances other than 8ohms. I would use the actual speaker motor cut out from an actual sacrificial donor speaker like in photo #4 above. It DOES actually move but even with just the dust cap, it will make noise. I have a number of these near my workbench and use them as dummy & test loads. I can hear a 1k hertz signal just fine w/out the cone & frame. So maybe cut away most of the cap too leaving only the part that holds the tinsel wires and that might make it totally silent? The speaker motor would be rated to handle whatever wattage you'd want to throw at it along with the rheostat being sized appropriately.

Finally, have we determined that an actual moving speaker motor is necessary or not?
« Last Edit: November 12, 2014, 09:53:33 pm by jojokeo »
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Offline Ed_Chambley

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Re: So, 2deaf, speaker attenuators
« Reply #56 on: November 13, 2014, 10:18:49 am »
Ed, there's too many things I want to comment on but your humor is great as always. Wish I had that soundproof room with the door  :laugh:
 
You said Sansamp, that's different than Samamp. I take it that you meant the VAC control?
First let me say the only snidemaster is Jim.  Snide meaning insinuating in this regard.

2 Deaf, No I was not insinuating anything.  Your comments clearly disregarded the attenuation method used in the Samamp and took the time to point it out.  My comprehension skills are good enough to tell that.  I am sorry if you took me as being deceitful as I am not that type of guy.  I was agreeing with you, but it is not necessary to disregard an idea like the attenuation used in the Samamp because you assume it does not work for you.  The OP John was actually asking you for your thoughts and I should have not even commented since the thread was to you.

I will be checking out of this discussion.  I am truly sorry.  As Sluckey says, "Ed is very sensitive".  Now go ahead and believe that. :icon_biggrin:

Yes Joe, I was speaking to VAC control.  I will email you about it. 

Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #57 on: November 13, 2014, 07:57:38 pm »
What?  What did I say?!?!  Ed, you are officially out of my will for the name calling.  But before I do that my wife wants your plans for the soundproof room.   :think1: Hmmmm, I think my wife is out of the will too....


Guys, this has been a real eye opener for me.  I certainly had some strong opinions on what I thought was happening - and although I'm not truly convinced otherwise, it has given me something to think about.  That's why I like this place.  Again, if we are just talking about taking the top off a screamer, most of these attenuators will do well enough for the average fan.  However, the discussion seems to be going back and forth between, ultimate transparent bedroom levels that mimic on stage and in concert - to -  hey it has to sound good in a bar or studio.  In my mind these are two completely different things and applications.  Would it be nice to have both in one box?  Yeah, but I don't think that will happen.  Why?  Because I think we will have to do something completely different for each.  I hear the same comment with each model, "It sounds good 'till you start to really turn it down."


JMHO
Jim


ps.  Sensitive Ed...  I'll have to remember THAT!!! :l2:

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Offline jojokeo

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Re: So, 2deaf, speaker attenuators
« Reply #58 on: November 14, 2014, 08:52:47 am »
1) Again, if we are just talking about taking the top off a screamer, most of these attenuators will do well enough for the average fan.
2) ...ultimate transparent bedroom levels that mimic on stage and in concert - to -  hey it has to sound good in a bar or studio
3) In my mind these are two completely different things and applications.  Would it be nice to have both in one box?  Yeah, but I don't think that will happen.
4) Because I think we will have to do something completely different for each.
5) I hear the same comment with each model, "It sounds good 'till you start to really turn it down."
6) ps.  Sensitive Ed... 
1) Yes, especially if played in a bar or gig situation. There's still plenty of frequency response & high end still available and in fact you may not need or want too much high end anyway!?
2) transparency or tone etc, again this isn't nearly as important in live situations like our sensitive ears can be in home & studio
3) yes maybe to a point, but why not? It's only a matter of personal taste, choice, or how sensitive or anal about things we choose to be (just like the difference with type A or B personalities)
4) maybe again but not necessarily. I've got several "mules" that works great in all kinds of situations and power requirements. Plus I keep a bunch of various power level heads available to achieve whatever I need for the situation (just like Ed & others here have - that's the great benefit of what we can make and do for ourselves)
5a) that could be a number of factors; a simple & obvious one would be that the speaker isn't compressing the same therefore loses it's sound as it's turned down no matter what amp/tubes are pushing it.
5b) my bass player next to me says & thinks the opposite  :laugh:
6) it's very easy to read into comments typed out w/out hearing a person's voice inflections and non-verbal communication (facial expressions) that we all experience with face to face conversation. Some are better than others at typing it or interpreting it so before offense is taken, it would be appropriate to not jump to conclusions & give others a chance one way or another before going from a and b, all the way to z. This is just my opinion and I will not even attempt to speak for Ed or anyone else. It can take people time to realize this and then to begin to improve their skills in doing so (this is meant more for the people that are expressing opinion, not interpreting it). Most are here to learn & help being the underlying intentions but lines can get blurry in a hurry for a very large number of reasons. I think we're pretty good at sniffing that out and is what keeps this place so great.

*Mr. Schneidly you have perfected the good natured biting humor tightrope of which you daily walk where others fear to tread  :l2:
« Last Edit: November 14, 2014, 08:58:49 am by jojokeo »
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Offline John

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Re: So, 2deaf, speaker attenuators
« Reply #59 on: November 14, 2014, 07:53:09 pm »
Onliest thing I knows is, this is my most successful thread, evahhhh.  :icon_biggrin:
Tapping into the inner tube.

Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #60 on: November 15, 2014, 12:38:38 am »
John,
This is a cool thread.  Good stuff.  That's what makes this site so great when folks can throw ideas around on a problem and have a hearty discussion.

Jojo,
You suck............the wattage out of the final application and it will totally change the dynamics of the product - the speaker compression being one of many details involved.  That's why I think the bedroom level solution may have to be actively/artificially altered instead of passively altered.  Oh why am I even bothering talking to a guy who plays R&R with a music stand in front of him!!!! :dontknow:

Yer pal,
Jim :icon_biggrin:

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Can we have everything louder than everything else?

Offline jojokeo

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Re: So, 2deaf, speaker attenuators
« Reply #61 on: November 15, 2014, 09:13:17 am »
Jojo,
You suck the wattage out of the final application and it will totally change the dynamics of the product - the speaker compression being one of many details involved.  That's why I think the bedroom level solution may have to be actively/artificially altered instead of passively altered

Yer pal,
Jim :icon_biggrin:

 :l2: Ha! Remove those little dots and you're on to something. Now read it again as it should be written.........(<I'll use them here instead where they should be)
To steal ideas from one person is plagiarism. To steal from many is research.

Offline 2deaf

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Re: So, 2deaf, speaker attenuators
« Reply #62 on: November 15, 2014, 03:13:32 pm »
Onliest thing I knows is, this is my most successful thread, evahhhh.  :icon_biggrin:

I'm glad you brought it up.  I've learned all kinds of things, some of it about attenuation.

:l2: Ha! Remove those little dots and you're on to something. Now read it again as it should be written.........(<I'll use them here instead where they should be)

So, I guess you guys are ribbing each other on this forum and I wasn't picking up on it.  Ed had a valid point, anyways.


I watched a guy demonstrating a Samamp by playing the same Little Wing licks at different settings.  The VAC feature was very impressive through my JBL powered monitors. 

Offline HotBluePlates

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Re: So, 2deaf, speaker attenuators
« Reply #63 on: November 15, 2014, 05:04:53 pm »
Yeah, Jim, Ed & Joe give each other good-natured ribbing frequently. I've misinterpreted it before, but they make their intent known quickly.

Just don't get Jim started on Tubenit's Tele...   :cussing:

Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #64 on: November 15, 2014, 09:30:08 pm »
HBP, you really suck........the fun out of my intent to bring Tubenit out of his misguided relationship with a worthless guitar.  I thought you were on MY side!  YOU are out of my will too.

Jim :m8

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Can we have everything louder than everything else?

Offline HotBluePlates

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Re: So, 2deaf, speaker attenuators
« Reply #65 on: November 16, 2014, 08:24:41 am »
Wait... I was in your will??!? I was to inherit the Major?!  :BangHead:

Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #66 on: November 29, 2014, 01:02:36 pm »
OK fellas, in the process of modifying my Hammond and looking at Leslie options/homebuilt cabs, etc...  I got to looking at the Leslie 147 schematic.  For those who may not be aware, this cabinet could be used with the Hammond Console models (B3, C3, etc), as they had a direct line out - OR they could be used with a conversion kit on the Spinets (M3, L1XX, etc.) and a different input setting on the 147.


What got me thinking about this setup is while walking down memory lane with an old band I saw back in the early 70's, I came across a recording of one of the BEST Hammond/Leslie growls I have ever heard.  Upon doing some research, the player is using an L1XX with a 147 and from what I have read, nothing in between.  (Although you can turn up the drive slightly on the Hammond L) Here is the example for your sonic reference 1:00 on or 6:00 on....:


https://www.youtube.com/watch?v=Ee7e5G60lbk


So why am I bringing this up? I mentioned in an earlier post that I thought bedroom/small bar, and possibly recording studio attenuation levels could not be achieved with passive components, but with active components.  SO, the spinets had a 15watt amp.  The 8 ohm speaker output from the spinet runs direct to the 147 (there is no line out).  Looking at the front end of the 147 amp we have a 10watt 8ohm resistor across the input, running to a 10K VR (I wonder what the rating is?) into a 12AU7 phase inverter driving (2) 6550's for ~40watts.


Now, what I don't know is how loud the Frumpy keyboard player was playing.  What I can tell you is, I know what an L sounds like - with it's built in speaker or direct into my Marshall (you can pull the preamp off but you bypass the reverb and some drive).  The L sounds different from the B or C.  It is brighter and has a more subdued percussion and little key click.  The recording I posted above sounds EXACTLY like mine.  There is no loss of highs.  There is not that "wet blanket over the speaker" dull sound.  None of the things we associate with typical resistance attenuation is there.


So, is the secret possibly running our favorite amp into maybe a smaller amp with some tone tweaks (if needed) a possibility?  If I run my spinet wide open at a blazing 15 watts, how hard am I hitting the front end of the 12AU7?  Obviously that depends on where I have the 10K set, but we don't have to have 6550's in the power section.  We could ultimately do PRR's halfwatter if need be.  Is that wonderful growl coming from the phase inverter being slammed?  Leslie did an amazing job with this as it appears to be pretty much sonically transparent.  What do you guys think?


Jim

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Can we have everything louder than everything else?

Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #67 on: November 29, 2014, 01:23:58 pm »
Leslie 147 schemo




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Offline jojokeo

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Re: So, 2deaf, speaker attenuators
« Reply #68 on: December 06, 2014, 01:32:13 am »
I need to come up with an Inga attenuator  :help: :laugh:
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Offline Ritchie200

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Re: So, 2deaf, speaker attenuators
« Reply #69 on: December 06, 2014, 02:38:29 pm »
Haha! Sorry about that!

Jim

My religion? I'm a Cathode Follower!
Can we have everything louder than everything else?

 


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