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just strum
March 28th, 2009, 06:56 AM
What is involved in installing a stand-by switch on the Blackheart LG?

Also, what is the purpose of a master volume knob on an amp. What does it offer an amp as opposed to one that doesn't have one?

What is involved in installing one and is worth the time and money?

tunghaichuan
March 28th, 2009, 07:21 AM
What is involved in installing a stand-by switch on the Blackheart LG?

The easiest way would be to remove the pentode/triode switch and use that slot for the standby switch. Then you'd want to get a switch that would fit the hole, a DPDT. Connect it so that it interrupts HV.AC1 and HV.AC2 on the schematic.




Also, what is the purpose of a master volume knob on an amp. What does it offer an amp as opposed to one that doesn't have one?

What is involved in installing one and is worth the time and money?

A master volume is usually used to turn down the overall volume of the amp to get distortion at lower volumes. If an amp has a high gain preamp, you can get distortion/OD at comfortable levels. An MV also allows you to put an distortion/OD/booster pedal on the front end of the amp and drive the preamp tubes hard while keeping the overall level of the amp at lower volume levels.

On the BH5 Little Giant, (a Class A, SE amp without a phase inverter) you would replace R9 with a 250k audio/log pot. It gets a little more complicated with a push pull amp that has a phase inverter.

I would say that it is not worth the time or money with the BH5 Little Giant. To get OD at lower volumes, I'd consider this circuit (http://yeomansinstruments.blogspot.com/2008/07/vvr-greatest-thing-ever.html) istead.

tung

just strum
March 28th, 2009, 07:26 AM
Well, after first read (sort of clueless on what you are saying - google time), I think I will leave it stock, at least for now.

tunghaichuan
March 28th, 2009, 07:33 AM
Strum,


Well, after first read (sort of clueless on what you are saying - google time), I think I will leave it stock, at least for now.

I've modded the crap out of my Valve Juniors as the really needed it. I have not added standby switches to them, though.

The BH was designed and implemented much better, so no mods are really necessary. I haven't modded either one of mine. To tell the truth, you don't really need a standby switch. It only uses two relatively inexpensive tubes and they are still pretty easy to come by.

The BH is a great platform for pedals be it just one OD/Distortion pedal or a a whole pedal board full. It does not excel at cranked OD tone, though.

tung

just strum
March 28th, 2009, 07:50 AM
The BH is a great platform for pedals be it just one OD/Distortion pedal or a a whole pedal board full. It does not excel at cranked OD tone, though.

tung

My preference is clean, so I believe I will be ok. There is enough rave about these amps that when this one came about for $100 I decided it was time to buy.

Spudman
March 28th, 2009, 09:12 AM
I would say that it is not worth the time or money with the BH5 Little Giant. To get OD at lower volumes, I'd consider this circuit istead.

I'd leave it stock. The switch shouldn't even be an issue for you if you aren't on stage 5 nights a week and desire to leave it on during breaks between sets.

markb
March 28th, 2009, 02:37 PM
Master volumes turned up on amps in the 1970s as a way of driving the amp without excessive volume. The problem is that the sound of classic rock 'n' roll is that of a driving power amp and not the thin fuzzy drive of a preamp tube (the first use of fuzz was the result of a blown tube on an input channel). After introducing the MV line, Marshall even went further and added clipping diodes to their preamps making their "all valve" amps more like a valve power stage with a distortion effect built in. The trick is really to get the amp into "the zone" and use the guitar controls and your right hand to control the drive.

Hence the popularity of low watt amps. They allow you to drive the power amp at reasonable volumes producing all the richness that a valve amp should without blowing out your windows or getting visits from the police. Many a classic record was recorded with a 5 watt amp.

just strum
March 28th, 2009, 06:40 PM
I'd leave it stock. The switch shouldn't even be an issue for you if you aren't on stage 5 nights a week and desire to leave it on during breaks between sets.

Now how and the he11 did you manage to see my fantasy???

Based on your comment and the others, I think you are right.

BTW, did you see the 67 year old babe in the front row - hubba hubba. Doing the old folks home tour, she's one of the young ones and a real catch.

Spudman
March 28th, 2009, 09:26 PM
Now how and the he11 did you manage to see my fantasy???

Based on your comment and the others, I think you are right.

BTW, did you see the 67 year old babe in the front row - hubba hubba. Doing the old folks home tour, she's one of the young ones and a real catch.

She's taken good care of herself. One or two drinks and she's all yours. Holler if you need backup.
http://www.vul.bc.ca/v3/team/pictures/old%20lady.jpg

Rock and roll is a beautiful thing.

just strum
April 1st, 2009, 04:49 PM
Maybe I should start another thread, but I'll just go with the current flow.

My BH arrives this coming Monday and I was going to set-up the AD30VT. Would it be wise to have a switch that would allow me to switch from using it as a cab to using it as a standard amp? I figure I would have the jack wiring going to the switch and the amp wiring going to the switch, then wires leading to the speaker. Position 1 would be for using it as the AD30VT, position 2 for using it as a cab.

I figure if I don't do that, I would always have to go in through the back and switch the wires connected to the speaker.

markb
April 1st, 2009, 04:57 PM
Fit two jacks. One to the speaker side of the speaker cable, one to the amp side. Use a jumper cable between the jacks (make it short) when you want to run the AD to its internal speaker. This gives you an AD30 head, combo when you want it and a cabinet. If you mount the jacks on a recessed plate and use right angled plugs for the jumper it won't even stick out at the back.

just strum
April 1st, 2009, 05:03 PM
Fit two jacks. One to the speaker side of the speaker cable, one to the amp side. Use a jumper cable between the jacks (make it short) when you want to run the AD to its internal speaker. This gives you an AD30 head, combo when you want it and a cabinet. If you mount the jacks on a recessed plate and use right angled plugs for the jumper it won't even stick out at the back.

So by doing that, I would also have the option of running the AD to another cab when I finally get one set up later, yes?

just strum
April 1st, 2009, 05:04 PM
Okay, a "I know nothing about electronics" question. When I purchase the jacks, is there anything I should concern myself with besides size?

markb
April 1st, 2009, 05:16 PM
So by doing that, I would also have the option of running the AD to another cab when I finally get one set up later, yes?

Yep. Ultimate flexibility. Use two of these (Http://www.smallbearelec.com/Detail.bok?no=770). I'd cut a rectangular hole in the panel and mount them on something like the pre-drilled recessed plate at the bottom of this page (http://www.penn-elcom.com/Default.asp?MC=1102010&GC=31). Using a plate like this will cover up any ragged edges on the hole you cut.

just strum
April 1st, 2009, 05:38 PM
Yep. Ultimate flexibility. Use two of these (Http://www.smallbearelec.com/Detail.bok?no=770). I'd cut a rectangular hole in the panel and mount them on something like the pre-drilled recessed plate at the bottom of this page (http://www.penn-elcom.com/Default.asp?MC=1102010&GC=31). Using a plate like this will cover up any ragged edges on the hole you cut.

Mark,

How about a plate like the attached? How does the jacks on the right differ from the one you suggested (besides looks)?

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-287

markb
April 1st, 2009, 06:01 PM
That's all fine. Same (British) manufacturer even. The jacks don't really matter as long as they have enough threaded length to go through the plate and leave you a few turns on the nut.

just strum
April 1st, 2009, 06:04 PM
I have to find a local store so I can buy the stuff now and install it over the weekend. I don't think I could let the amp sit there without being able to use it - I would go insane.

just strum
April 2nd, 2009, 04:25 PM
I was looking at the AD30VT last night and trying to determine where to install the jacks. Since the entire back comes off, that would require me to disconnect the jacks every time I took the back off (not a common occurrence, but still a pain in the butt). That said, I am thinking of putting the jacks in the side.

Just throwing that out there.

TS808
April 3rd, 2009, 10:42 AM
Well, after first read (sort of clueless on what you are saying - google time), I think I will leave it stock, at least for now.

I have a Little Giant too and I think it's a cool enough amp to not require any mods (just my opinion).

I always run pedals through my Little Giant for more distorted tones; It's a surprisingly clean amp for the low wattage it puts out.

TS808
April 3rd, 2009, 10:46 AM
Maybe I should start another thread, but I'll just go with the current flow.

My BH arrives this coming Monday and I was going to set-up the AD30VT. Would it be wise to have a switch that would allow me to switch from using it as a cab to using it as a standard amp? I figure I would have the jack wiring going to the switch and the amp wiring going to the switch, then wires leading to the speaker. Position 1 would be for using it as the AD30VT, position 2 for using it as a cab.

I figure if I don't do that, I would always have to go in through the back and switch the wires connected to the speaker.

I've been seeing some Blackheart cabs showing up on ebay lately. I would opt to go for another cab. There's even a 1x10 Blackheart cab that is reasonably priced.

just strum
April 3rd, 2009, 04:21 PM
I've been seeing some Blackheart cabs showing up on ebay lately. I would opt to go for another cab. There's even a 1x10 Blackheart cab that is reasonably priced.


The four usual web places have the cab for $149, but then I ran across this

http://www.musiciansbuy.com/crate-bh110kit.html

plus some free stuff.

TS808
April 3rd, 2009, 07:30 PM
The four usual web places have the cab for $149, but then I ran across this

http://www.musiciansbuy.com/crate-bh110kit.html

plus some free stuff.

Cool! I bought stuff from them before...they always throw something in to sweeten the deal.:AOK:

just strum
April 4th, 2009, 01:53 PM
Mark,

How about a plate like the attached? How does the jacks on the right differ from the one you suggested (besides looks)?

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-287

When I was out today I tried to pick-up some jack plates, but I couldn't find any at the music shop or Radio Shack. I wanted to do the work on the amp today, but it looks like I will have to order the parts. I hate paying more for shipping than the cost of the item.