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View Poll Results: Which side should be the front?
Long 11 28.21%
Short 28 71.79%
Voters: 39. You may not vote on this poll

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Old 26th November 2012, 08:53 AM   #11
HpW is offline HpW  Switzerland
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Quote:
Originally Posted by Wavebourn View Post
Hi!

I have a dilemma, which side should be the face, with front panel?
Usually monoblocks have short face. But if to make the front panel on the long side it will be 19" rack mountable. Which road should I choose?

The front panel will contain only power switch and volume control. Rear panel will contain power socket, fuse, output binding posts, RCA and XLR sockets, RCA-XLR switch.
Below is a picture of my modified Cary SLM-100 with following changes:

1) Input on the front to have now signal trough the power & output and also a very short connection to the first input tube

2) Power switch on the back to avoid long power cables trough the chassis

3) the standby (connection to ground with a lift up resistor) switch & cables connection has been shorted and now use a relays.

Still open & research in progress (may some one helps in this regard ): the schematic for the real XLR / symmetric input while have only 2 * 6SN7 tubes...

HpW
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Old 26th November 2012, 09:22 AM   #12
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Having faced the same dilemma recently, I can say that the only way that sensitive signals do not pass near the power supply AND not have the input jacks right on the front, is to have the long face forward. Then again, you can take a cue from Ming-Da preamps (yes, them), and have the narrow face front, but the inputs on the side forward.
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Old 26th November 2012, 10:16 AM   #13
AJT is offline AJT  Philippines
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Quote:
Originally Posted by HpW View Post
Below is a picture of my modified Cary SLM-100 with following changes:

1) Input on the front to have now signal trough the power & output and also a very short connection to the first input tube

2) Power switch on the back to avoid long power cables trough the chassis

3) the standby (connection to ground with a lift up resistor) switch & cables connection has been shorted and now use a relays.

Still open & research in progress (may some one helps in this regard ): the schematic for the real XLR / symmetric input while have only 2 * 6SN7 tubes...

HpW

makes a lot of sense to me, this is also my prefference, but you know there are folks that find this arrangement ungly no matter how i try to explain the advantages...oh well......
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Old 26th November 2012, 12:37 PM   #14
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When I think in terms of MOSFET followers in this type of application, I think in terms of the TubeLab "power-drive" (because I am somewhat familiar with it). Whatever scheme specifics may be, such a follower concept does seem to open the doors to a very broad selection of drivers and also seems as if it should be "sonically invisible".
Two questions:
.......1) Is it sonically invisible?
and, 2) Are you contemplating a regulated screen supply?
It seems to me that screen supply regulation might represent the last link in a design of this basic description: dynamic maintenance of impedance, that is to say.
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Old 26th November 2012, 01:06 PM   #15
Bigun is offline Bigun  Canada
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power switch on back is a nuisance, have to reach over and behind everything to turn on/off
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Old 26th November 2012, 02:26 PM   #16
HpW is offline HpW  Switzerland
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Quote:
Originally Posted by Bigun View Post
power switch on back is a nuisance, have to reach over and behind everything to turn on/off
Well, for this I have a common power plain (and power filter) with all audio stuff on and a single common power switch for all.

HpW
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Old 26th November 2012, 03:09 PM   #17
Funker is offline Funker  Germany
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Default which side to front?

Hi Waveburn,

Wow, 4 GU50 that will give your amp the real grunt. For my taste, I would prefer it with the narrow side to front.

I made a test setup with 6 of the GU50. I drive them hard into grid current (B2) They drive 450W into the Load at 1000V plate and 250V g2 . What an amazing valve. My aim is to build a Bass Guitar amp with these.

73
Wolfgang


Quote:
Originally Posted by Wavebourn View Post
Hi!

I am building a prototype of the amp, it will be monoblock, 200W output, 4xGU-50.
I have a dilemma, which side should be the face, with front panel?
Usually monoblocks have short face. But if to make the front panel on the long side it will be 19" rack mountable. Which road should I choose?

The front panel will contain only power switch and volume control. Rear panel will contain power socket, fuse, output binding posts, RCA and XLR sockets, RCA-XLR switch.

Click the image to open in full size.

Click the image to open in full size.
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Old 26th November 2012, 03:13 PM   #18
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Talking perfect timing

Yesterday I was -just one more time- thinking what to do with the two big PTs that I have laying around. Wavebournes posts got me interested in the GU-50, so I checked out their availability, prices, specs, compatibility with my PTs. I could do 4 or 6 per channel. When I woke up this morning I say this thread... Now that's what I call a good start of the day
I'll be following this one.
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Old 26th November 2012, 03:57 PM   #19
djn is offline djn  United States
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I just voted for the wrong side. I would make the short side the front as it shows off those tubes nicely.
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Old 26th November 2012, 04:21 PM   #20
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Although I voted long front ...this 500W amp is 19"x18" square ...snags, no room available at the rear for AC socket and opposite side XLR inputs, for listening room and stage aesthesics I avoided front panel clutter as rt'angled entry of both IEC and XLR are around.
I'd admit getting the mechanical size of this amp into a 19" rack criteria wasn't easy.

richy
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File Type: jpg rear view.JPG (154.0 KB, 208 views)
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