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PostPosted: Tue Sep 29, 2009 6:45 pm 
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Mark IV

Joined: Wed Sep 12, 2007 6:41 pm
Posts: 845
Location: East Bay, CA
Lone Star Reeder Mod #2: The "Mid Mod"

Charles Reeder's original thread is here:
'Flabby/Muddy' Bass on the Lonestar? Want to change it?
Lots of additional information and theorizing throughout the original thread, some further mod ideas, and one or two diagrams.

BASIC MOD DESCRIPTION:
Add a short jumper connection between the middle and left left terminals (or wiper and high side) of each channel's Midrange potentiometer. Optionally, you can insert switches in the middle of this (these) connection(s), though you'd then have to decide where to drill a hole in your chassis or repurpose an existing one.

EFFECT: Reduces flubby bass response, especially at higher volumes; allows more precise control of bass and midrange, with more than enough low-end still available.

NOTE: Several users (self included) have reverted Channel 1 back to its un-jumpered stock configuration. The benefits of this modification seem to be more pronounced on Channel 2, and have been deemed as less effective or desirable on Ch1. Some feel that higher-volume muddiness is improved on both channels, but there may be a sacrifice of some of Channel 1's "mojo" at less-than-super-loud levels.

YOU MIGHT TRY THIS MOD IF: You feel your Lone Star's low-end response is muddy and has less definition than it seems like it could, especially at higher volumes.

YOU SHOULD NOT DO THIS IF: You are perfectly happy with the performance of your Lone Star as-is.

HOW THE MOD WORKS

Charles discovered this possibility when looking at a site for modifying Fender Hot Rod Deluxes, which, apparently, share the same symptoms in the ears of some of its enthusiastic user base. Here's an excerpt from the post Charles quoted:

Quote:
If you look at most of the older (Fender) designs with a midrange control (such as a vintage Twin Reverb), the Mid control is wired with the wiper tied to the high side of the pot, just like the bass control. This effectively turns the potentiometer into a variable resistor (a variable resistor is a 2-terminal device, whereas a potentiometer is a 3-terminal device that is used as a voltage divider, as in a volume control). On these amps, you can turn the volume all the way off by turning all the tone controls to 0. This then allows you to more precisely balance the lows and highs coming through the tone circuit.

Again, I have to confess my inability to make much sense out of this, other than to say that this does seem to give the Mid and Bass effect more independent control of their parts of the tone range. My own amp tech claims this should have no effect on the tone, though there's agreement here that the effect, subtle as it is, is audible.

SKILLS/MATERIALS NEEDED: Basic soldering competency; ability to take great care while tinkering in close proximity to high-voltage capacitors.
Also, have onhand a short bit of insulated wire -- literally a half an inch will suffice. A light gauge is fine.

HOW TO DO THE MOD

SAFETY NOTE: If you are at all uncomfortable with electronics, soldering, or taking care around extremely hazardous electronic components, DO NOT DO THIS. Please take the time to understand the safety requirements when opening and working with the insides of tube amps. Especially: Do not touch the blue cylindrical capacitors. Even when the amp is unplugged, they likely will contain enough static charge to cause you serious, deadly harm if touched and allowed to dump all that energy into you.

The instructions below assume:

- You understand the important safety precautions.
- You know about the LS' 5th screw, threaded up through the underside of the amp, which is for grounding and vibration dampening.
- You know how to remove the amp chassis from the cabinet, taking care to place it on a steady and well-lit work surface; and you have done this.

1. Use a small flathead screwdriver to loosen and remove the knob and plastic washer from the Mid control on Channel 1. Loosen and remove the short hex nut around the threaded collar in front of the pot. The pot should now be sitting in its hole in the chassis, loosely.

2. Push the Mid pot for Channel 1 back into the amp, still connected but out of the way. You need to do this in order to access the Mid pot for Channel 2.

3. Look down at the Mid pot for Channel 2 as it sits in the chassis. Notice that the pot has 3 terminals, only two of which are connected to any wires (the RIGHT and CENTER, as seen from the front).

4. Leaving the existing connections as-is, solder a short bit of insulated wire between the ends of the LEFT and CENTER terminals on Channel 2's Mid control. Be careful not to drip any solder onto the PCB.

5. Re-affix the Mid pot for Channel 1 and decide if you want to try this with Ch1 or not. Current consensus is probably: Not all that worth it, Channel 1 is pretty perfect as-is. But it's an easy mod to reverse (just unsolder or clip the added connection), so gauge your own needs.

6. Reattach knobs, reassemble amp + cab, and don't forget your AC and speaker connections.

7. Enjoy.

TESTIMONY

Quote:
Well, after this weekend, I would have to say that the midrange "reeder" mod is a success. I didn't tell the soundman or my drummer (who uses in-ears) what I did to the amp. After the 1st night I asked, "How does the amp sound?" The soundman said, " I had to turn you up a little and the guitar (Telecaster) sounds really clear tonight." He said that the LSC sounded more vintage than before. The drummer said that the guitar sounded less muddy. I would have to say that I did turn the mids up a little more than before the mod. I used to run them about 9 O'clock, now about 11 to 12 O'clock. I used channel two alot more for the Country stuff and just used my volume pedal position up and down for solos and louder parts of the songs. This mod is probably not for Metal guys, as the area of mids that seem reduced are in the 400 to 800 Hz range. But, the bass control now seems more active above 1 and between 3 O'Clock. I could reach back and dial in all the thump that I needed for and Classic Rock stuff. But, for Country and Blues music and if you have a Gibson guitar I would recommend it! My vintage 335 sounds very "Carltonesque" with this mod.

First impressions are that the difference is subtle at the levels I can play at home, though I can hear it. It does seem to focus the ranges that the controls affect, which is nice. So far I don't miss anything about the response I had before; I was concerned I might be unhappy at lower levels, but I can turn the bass up a lot more than before and it's fine.

This mod... goes the rest of the way by drying out the gain a little more. It removes the background murkiness, that low-end mud that the gain signature seemed to literally be standing in a pool of: everything above a certain point was nice and clear, but below that point it was submerged in muck that blurred the lower harmonics. Now it's like you can hear everything, and those harmonics have been set free. The gain is crisp, from top to bottom. Ch1 and Ch2 both benefit from this.

Couple of other things: I never really gave the Thicker setting much attention before; a while back after spending some time with the Thick setting I decided that I liked the Normal gain setting best, as it seemed the most open and uncolored. The other two seemed to cloud and flatten the tone too much for me. Now however, the other two settings seem to really step up and -- with the Strat at least* -- the Thicker setting really sings. It's actually amazing how transparent it remains, while somehow managing to really juice the gain with some real muscle. I may have to make it a practice to flip that switch when I use the Strat.

And I may be tripping, but it seems like I can get good harmonic feedback more easily now. Maybe it's all a result of the 2 mods together that I've allowed my gain & drive controls to creep a little higher... but I don't remember such voluntary feedback like this before. It's pretty awesome.

It stands out the most on ch2 with the drive on and a nice gritty tone, but I also was getting a clearer more pronouced low freq response on the clean channel with all the other wonderful harmonics unchanged ala Jerry Garcia. (awesome!)


Thanks to plan-x, thirstypirate, loudguitars, Chrissmoth, and all you crazy modders out there.

And once again: A big thanks to (Doctor) Charles Reeder for his ridiculously productive tinkering! ("Honey, what are you doing down there??")

_________________
LP Std Gold Top | LP Special | AmDlx Strat | AmStd Tele | SG Std 60s | ES335 | FSR Tele
Lone Star Classic
Lone Star Special
Electra Dyne
Mini Rec 25
TransAtlantic 15
Lone Star 27, 23 & 19, RA 27 1x12, WBCB 1x12 Cabs

http://www.damonwood.com


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PostPosted: Tue Sep 29, 2009 7:18 pm 
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Single Recto
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Joined: Sun Oct 15, 2006 11:20 pm
Posts: 1096
Location: CA, Mojave desert
That surpasses anything I would of put together by a mile. I knew you were the right man (geek) for the job. Great job djw.

P.S. Now there's a drive mod to be dealt with. LOL :lol:

_________________
Recto-Verb 25 head
Lonestar Classic (LSC) 2x12
.
Plan-x
https://myspace.com/wichmanbrewster/music/songs


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PostPosted: Tue Sep 29, 2009 7:22 pm 
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Mark IV

Joined: Wed Sep 12, 2007 6:41 pm
Posts: 845
Location: East Bay, CA
plan-x wrote:
That surpasses anything I would of put together by a mile. I knew you were the right man (geek) for the job. Great job djw.

P.S. Now there's a drive mod to be dealt with. LOL :lol:


Thanks, bro. Yeah, gotta get on that drive mod. eeek (rhymes with "geek").

_________________
LP Std Gold Top | LP Special | AmDlx Strat | AmStd Tele | SG Std 60s | ES335 | FSR Tele
Lone Star Classic
Lone Star Special
Electra Dyne
Mini Rec 25
TransAtlantic 15
Lone Star 27, 23 & 19, RA 27 1x12, WBCB 1x12 Cabs

http://www.damonwood.com


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PostPosted: Mon Apr 19, 2010 7:38 am 
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Mark II

Joined: Fri Apr 02, 2010 8:06 pm
Posts: 66
I haven't tried this mod but if you want to get rid of the mud and the farty bass try the bias mod . I did it on my lonestar and man what a difference.


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PostPosted: Wed Dec 15, 2010 11:44 pm 
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Mark III

Joined: Fri Oct 05, 2007 3:51 pm
Posts: 360
Lately I've seen quite a few people tried or want to try this mod hoping that it would somehow improve the bass/mid. However most who has done the mod don't notice any difference. Thought I'd chime in:
The reason (and also a best practice) for tying the middle lug to the 'other' open lug is for reliability, and it has no tonal benefit. Over time the pot wiper can wear out and have bad contact to the pot's resistive track. When the wiper is in this 'bad' spot, the pot is an open circuit and could cause issue. So by wired the wiper to the open lug, when the wiper is in a 'bad' spot, the circuit still sees a resistance that's of the pot's value. You can check this out yourself by taking a pot and measure its resistance with/without a jumper wire, the values are identical.
There's a lot of 'mojo' talks so I hope this helps clarify a few things. Again if you hear an improvement or difference then more power to you, rock on.


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PostPosted: Fri Jun 08, 2012 8:44 am 
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Mark II

Joined: Thu Jun 07, 2012 11:49 am
Posts: 100
When removing the chassis from the LSS, what do you have to do with the grounding/vibration screw. I haven't worked on a Bogie before. I assume the other 4 screws hold the chassis. Is there a slide like in most Fenders where the chassis can set as you slide it out?


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PostPosted: Thu Jun 14, 2012 1:59 pm 
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Mark II

Joined: Thu Jun 07, 2012 11:49 am
Posts: 100
I installed this wire while I had it out to do th Gain Pot swap. Also opens the amp up and removes the blanket sound.

Would anyone want to post some good settings for Blues? I stayed away from this amp for far too long cause it had to many knobs.

I guess I don't have a consistent grip on tweaking.

VR, Ron


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PostPosted: Tue Jun 19, 2012 2:22 pm 
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Mark II

Joined: Thu Jun 07, 2012 11:49 am
Posts: 100
The grounding and Anti vibration screw that runs up thru the chassis and touches the shield at the top of the amp. I found, you don't have to do anything with the screw. I do wish the chassis had a shelf to slide out on. Mine dropped, no damage tho. I was expecting similar to a fender ledge.


Last edited by rfrakes on Sun Jul 06, 2014 1:58 pm, edited 1 time in total.

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PostPosted: Sat Jul 05, 2014 9:18 pm 
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Bottle Rocket

Joined: Sat Jul 05, 2014 7:22 pm
Posts: 9
The black shadow speaker that comes with the lonestar is very bassy and dark sounding. If you replace that speaker with a less bassy speaker then the lonestar will sound much less bassy (dark)... I replaced the speaker and it's much less dark sounding. Try this before a mod!!


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