T.R | Title | User | Personal Name | Date | Lines |
---|
3075.1 | | RICKS::CALCAGNI | more zip stupid juice | Mon May 01 1995 09:11 | 13 |
| How about another idea; instead of encasing all or most of the amp,
do it just to an external speaker, say a 12". The box totally encloses
the speaker and a microphone, just the wires or jacks running out. This
is a studio trick I've heard and read about; I think the term is "speaker
coffins" (cause the speaker is buried alive?). This has the added
advantage of you can run pretty much any amp you want through it, not
just the Twin; also avoids the heat considerations you mentioned.
Didn't GP or some similar magazine have a DIY article for building one
of these?
/rick
|
3075.2 | | MPGS::MARKEY | The bottom end of Liquid Sanctuary | Mon May 01 1995 09:23 | 24 |
|
Have you ever considered one of the so-called "power soakers"
that are on the market? (Marshall and Rockman both make one.)
They reduce the overall volume output of the cabinet while
(supposedly) not effecting the tone to any appreciable degree.
I assume that if you are thinking about putting the amplifier
in a box, you are considering micing the speakers. You won't
be able to build a big enough box to do any sort of ambient
micing, so you'll be limited to close micing; which, in theory,
gets you back to the emulated speaker outputs.
What I would suggest you do is get yourself a good graphic
Equalizer and run the uncompensated speaker outputs from your
preamp through it. Experiment with the settings. Most speaker
emulators are nothing more than fixed EQs, and if you can't
find one to fit your taste, then using a graphic EQ and
creating your own settings may be more to your taste.
There was an article in one issue of the ADA company mag about
good EQ settings for speaker emulation. I will dig it out...
-b
|
3075.3 | Now why didn't I think of that | COPCLU::SANDGREN | Keep it simple | Mon May 01 1995 09:24 | 8 |
|
Re. Rick: that sounds like a really good idea! If you anyone
know more about building such a box, I'd like to know! I guess
I'll have to buy a speaker type for closed cabinet...? And
then what would be the best speaker for the twin..?
Poul
|
3075.4 | | COPCLU::SANDGREN | Keep it simple | Mon May 01 1995 09:30 | 7 |
|
re. 3: more ideas! But I think one of the elements of the singing tone
of the twin is how much 'drive' the speaker get from the amp...but
there's room for a lot of experimentation here...
Poul
|
3075.6 | Closet-freaks | MILKWY::JACQUES | Vintage taste, reissue budget | Mon May 01 1995 09:52 | 48 |
|
I know what you mean about preamps. Most speaker-emulator outputs
tend to sound bland. The only one I've ever heard really good
reviews on is made by Groove Tubes. It has a 25 watt tube power
amp coupled with a patented speaker emulator circuit which uses
"Inductive Loading" to simulate a speaker. I believe Groove tubes
now sells the speaker emulator as a separate rack-mount unit. These
are not cheap products by any means. The preamp is about $1k and
the speaker emulator is about $500. The preamp can be used to
drive a speaker in stead of the built-in speaker emulator. I've
heard rave reviews about this rig, but I've never actually tried
one. NYC amplifier guru Harry Colbe also offers a speaker emulator
that works in much the same way as the Groove tubes unit. Again
not a cheap option.
Besides building an isolation box, you should also consider the
following:
1. "The Twin" can be run with only 2 power tubes in stead of 4.
Check your owner's manual. I believe the 2 middle tubes are
removed and the outer 2 tubes remain. You also have to change
the setting on the impedance switch. The manual will explain
the correct method. If you run the amp in the 25 watt mode
with the 2 tubes removed, the amp will only produce about 15w.
2. Place the amp inside of a closet. Insulate the inside of the
closet with heavy carpeting, or rubber padding, including the
floor under the amp. You can stick a mic inside the closet.
This gives the amp a little more room to breath than a small
box.
3. A lot of people swear by the little "Red Box" speaker emulator
made by Hughes and Kettner. These will accept a line level input
or they can be used in series with the speakers in your amp.
4. "The Twin" actually has 2 preamp outputs. One is the balanced
Canon connector on the back of the amp. The other is the
effect send jack. The efx send on "The Twin" has 3 differant
levels controlled by a switch. Experiment with differant
switch settings for best results.
I believe there is a note in here somewhere about the Groove
Tubes preamp. I'll post a pointer if I can find it.
Mark
|
3075.7 | | USPMLO::DESROCHERS | Was this ignorance or bliss... | Mon May 01 1995 10:13 | 9 |
|
This month's GP has a review of new power soaks (all from the
same company). They had switches for 1/4 power, 1/2, 3/4, etc...
Seemed like a good review. Somewhere in the $350 range.
Tom
|
3075.8 | | MPGS::MARKEY | The bottom end of Liquid Sanctuary | Mon May 01 1995 10:19 | 8 |
| >Power soaks are known to wreck amps and void warranties...
I don't know why this would be. Essentially, a power soak is
a voice coil (an inductor) without a radiating device (a
cone). Electrically, it's a speaker as far as the amp is
concerned.
-b
|
3075.9 | SR&D units were notorious. | MILKWY::JACQUES | Vintage taste, reissue budget | Mon May 01 1995 10:53 | 11 |
| The original "Power Soak" designed by Tom Sholz did have a reputation
for destroying amps. These units were essentially a decade resistor.
The knob on the front selected from various power-resistors built
into the unit. These were made to use with a speaker. I think the
problem with these units is that the load presented to the amp was
not what the amp needed to see. Also, people were cranking their
amps much higher than they normally would (ie: running the amp on
10 continuously).
Mark
|
3075.10 | | POLAR::KFICZERE | | Mon May 01 1995 10:55 | 10 |
| Fwiw,I just swapped me soak for a Boss Turbo Over Drive pedal.I can
*with out a doubt* say that the soak *does* effect the tone of your
amp.To make a long story short,i run a silver face Fender Bassman with
no master volume.I figured the soak would be ideal.What i found was
that the only time i liked the sound coming from it was when it was
wound to eleven (cranked to full power).I figured i might as well not
be running it at all.Must be something to do with letting those 4-10's
"breathe."
-kev
|
3075.11 | this must be the ticket | COPCLU::SANDGREN | Keep it simple | Tue May 02 1995 05:14 | 23 |
| Thanks for all the input. I think I like the idea of a modifying
my amp to 15 W and build a small box for 1X12 speaker. Imagine
something like this:
------| |----------| |------
| |
| ______ |
| / \ |
|---| |---/ \---| |---|
| speaker |
|---====== |
| mike |
| |
------| |----------| |------
I could then experiment with covering the holes to get an optimum
of sound quality/insulation. I think I'll buy myself a Celestion
30W vintage speaker for this setup. How do you like this idea?
Poul
|
3075.12 | Pierce your speaker for perma-fuzz | KIRKTN::JHYNDMAN | | Wed May 03 1995 11:15 | 11 |
| Re .10
If that's the case, could'nt you just use an old speaker with
the paper cone cut off it ? I wonder if it would make any sound at
all? Could be interesting....I might try it tonight, I've got a speaker
from an old Vox amp that I've never liked the colour of, kinda muddy
blue 8-) 8*)
Jim.
|
3075.13 | yeah, those speakers are real dogs :-) | RICKS::CALCAGNI | more zip stupid juice | Wed May 03 1995 12:06 | 4 |
| the de-coned speaker trick is commonly used by amp repair techs as a
dummy load, when they want to run some realistic signal levels through
an amp on the bench.
|