Charles Reeder
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This is about another Lonestar Modification that I ‘stumbled across’. Yeah, I do seem to stumble a lot.
Once again…as I stated (over and over again) when I posted my Lonestar Channel-2 mod; if you are perfectly happy with the sound of your amp ‘as-is’ then for goodness-sakes’ leave it alone! Nobody is trying to convince you that you need the mod…if you ‘need’ it…you’ll know it!
There frequently arises talk about the Lonestar having ‘flabby’ or ‘muddy’ bass…and I think there is a certain amount of truth to that. I love the sound I get from my Lonestars…but I kept thinking it would be nice if I could get rid of some of the ‘flab/mud’. With the gain up rather high on either channel…when playing some low notes… there seems to be too much loss of definition in the bass…even more so than with the midrange and high notes. Well; I didn’t go looking for a way to solve that but I stumbled across one.
I have a Fender Hot Rod Deluxe…and many people have the same complaint about the bass on the HRD….that it is ‘too flabby’…that it ‘muddies’ things up. There is a site for modding the HRD. http://studentweb.eku.edu/justin_holton/bias.html.
If you go to that page you will see a section for ‘modifications’. I clicked onto the ‘James Vanden Berg Mods’ http://studentweb.eku.edu/justin_holton/jvmods.html.
Once there I found the following description of the Hot Rod Deluxe’s flabby-bass problem and the simple mod that fixes it. The following except is the midrange tone pot mod from the ‘James Vanden Berg Mods’ on the ‘Unofficial Fender Hot Rod Deluxe’ site:
(Remember the excerpt below is talking about the Hot Rod Deluxe…It seems almost as if they are describing the bass on the Lonestar!)
TONE CONTROL MODIFICATION TO BETTER CONTROL BASS RESPONSE
Why does this amp sound so flabby in the low end? Part of the reason lies in the speaker/cabinet combination. I’ve plugged this amp into other speakers to compare and found that the stock speaker/enclosure seems to really favor the bottom end, particularly for a 1-12 combo. This is great, because it means that the speaker and cabinet are very efficient for these critical lows, and if we can control the amount of bottom end the amp sends to the speaker, we can get great volume without working the amp too hard. The problem lies in the tone control section. I compared this circuit with other vintage Fenders, and the most critical difference is in the way that the Midrange control is wired. If you look at most of the older 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.
The Mid control on this amp is a 25kA pot. (“A” stands for audio taper). Thus, the stock circuit in this amp puts 25,000 ohms at all times between the bottom of the bass control and ground. On vintage Fenders without a mid control, the resistor in its place was usually only 6.8k. On models with a mid control, such as the Twin Reverb, the pot was only 10k, so even with the mid turned up all the way, it didn’t have the same low-end response as the stock circuit in this HR Deluxe. The larger the value of this midrange resistor, the more bass and low-mid the amp has, regardless of the setting of the bass control.
Have you ever seen a “Loudness” switch on an older stereo? The Loudness circuit boosts the bass and treble and is intended for low-volume situations to compensate for the fact that the human ear hears midrange frequencies (where most speech resides) more acutely at low levels than deep lows or high trebles. As volume increases, this effect reduces. If you play a stereo at high volume with the Loudness switch engaged, it can sound flabby because the bass frequencies are now over-amplified for our ears. This is precisely what’s happening with this Fender HR Deluxe. It sounds great at low levels, but the bass overwhelms the tone at higher volumes.
Justin's comments: Instead of using wire I took a small piece of solder and melted it into place. This creates a very unobtrusive jumper that's easy to remove. Be sure to test your jumper with an ohm meter to make sure it passes current.
Fixing this takes very little effort:
Follow steps 1 and 2 above. Solder a jumper between the left and middle terminals of the mid control (when facing the amp from the rear, as you would be when working on it). That’s it. You can now reverse steps 1 and 2 and try it out. If you did it right, you should now be able to turn your volume down to 0 by turning all of your tone controls to 0. More importantly, you can now dial in just the right amount of low end with the mid and Bass controls. Remember, they’re interactive. The higher you set the mid control, the more bass you will get.
END of Fender Hot Rod Deluxe MOD excerpt.
NOW BELOW: THE RESULTS I OBTAINED ON MY Fender Hot Rod Deluxe AND MY Mesa Boogie Lonestar:
Well I tried the mod on my Fender Hot Rod Deluxe…and it worked…very-very well
So, I started wondering if the Lonestar would benefit from a similar mod…and... could a Lonestar even be modded that way? Finally a few days ago I opened up my LSC Head and checked out the ‘midrange’ pots.
On the Fender HRD mod; the center contact on the pot is jumpered to the contact on the left. That is because on the HRD; the pot is mounted to the circuit board from the top…upside down… (So the contacts are facing down).
The Lonestar has ‘flying-leads’ and the pots are mounted with the contacts facing upwards. So with the Lonestar…I needed to run a ‘jumper-wire’ on the midrange controls on both channels FROM THE CENTER CONTACT TO THE CONTACT ON THE RIGHT. This has got to be the easiest ‘mod’ I’ve ever done! It is necessary (on the Lonestar) to do it to 2 midrange pots (unlike the HRD which has only one midrange)…but it was still easier because I had to partially remove the circuit-board from the HRD in order to do the mod on it.
I REPEAT: All the mod involves with the Lonestar is soldering a ‘jumper-wire’ from the middle contact of each midrange control to the contact on the right. (The middle and right when viewed from the back of the amp)
With the Lonestar; I only had to remove the midrange pot for Channel-1 in order to gain access to the pot on Channel-2… by being very careful I didn’t have to remove the Channel-2 pot. I carefully heated the center contact with my soldering-iron and pressed a very slim wire into the hole next to the gray wire already there. The contact on the far right has nothing soldered onto it; so there was no problem at all soldering the ‘jumper’ wire to it. Once Channel-2 was done; I put Channel-1’s midrange pot back in and soldered the ‘jumper-wire’ to it. I reassembled the amp and proceeded to try it out.
Wonderful ‘tight’ bass! There is still plenty of bass on tap…but it doesn’t ‘muddy-up’ the other frequencies and it retains definition longer even with the gain up. I A/Bd the modded head against my LSC Combo to make sure I was really hearing the dramatic improvement that I thought I was. It was a definite improvement. Within the hour I had modded the combo too.
Stock; the Lonestar almost seems to be pushing some ‘sub-bass’ with very low frequencies that are almost inaudible…and that bass seems to ‘leech’ power from other notes as well as ‘bottoming-out/muddying’ the audible low notes. This mod seems especially useful when turning up the gain on channel-2…but it definitely helps both channels. Don’t worry…the LSC still retains PLENTY OF BASS!
NOTE: I had serious doubts about whether this mod would actually do anything useful for the Lonestar…so I ‘hedged-my-bets’ and used long sections of wire with ‘dpt’ mini-toggle-switches attached for the test on the first Lonestar. That way if I didn’t like the effect of the ‘mod’ I could merely ‘turn it off’…without having to immediately tear the amp down to remove it. I let the wires with the switch ‘dangle’ out of the chassis for the test. Now, I can either remove the toggle-switches or find a good place to mount them…when I feel like it. I may actually keep the toggle switches in the circuit as that gives some more versatility. You could do the mod with toggle-switches attached too...in case you are unsure about whether you will like the mod. Then by 'flipping the switch' you can conduct your own A/B comparison test.
REMEMBER: Always be super careful when doing ANY work inside an amplifier! Dangerous High Voltages Inside! If doubtful get a professional involved!
I don’t know if ‘flabby/muddy’ bass’ is an issue with you or not; so I don’t know if you will be motivated to try the mod,…but I figured I’d tell you about it as a possible solution. YOU decide if you need or want it…based upon YOUR experience with the amp…NOT MINE or anyone else’s.
Cheers: Charles
Once again…as I stated (over and over again) when I posted my Lonestar Channel-2 mod; if you are perfectly happy with the sound of your amp ‘as-is’ then for goodness-sakes’ leave it alone! Nobody is trying to convince you that you need the mod…if you ‘need’ it…you’ll know it!
There frequently arises talk about the Lonestar having ‘flabby’ or ‘muddy’ bass…and I think there is a certain amount of truth to that. I love the sound I get from my Lonestars…but I kept thinking it would be nice if I could get rid of some of the ‘flab/mud’. With the gain up rather high on either channel…when playing some low notes… there seems to be too much loss of definition in the bass…even more so than with the midrange and high notes. Well; I didn’t go looking for a way to solve that but I stumbled across one.
I have a Fender Hot Rod Deluxe…and many people have the same complaint about the bass on the HRD….that it is ‘too flabby’…that it ‘muddies’ things up. There is a site for modding the HRD. http://studentweb.eku.edu/justin_holton/bias.html.
If you go to that page you will see a section for ‘modifications’. I clicked onto the ‘James Vanden Berg Mods’ http://studentweb.eku.edu/justin_holton/jvmods.html.
Once there I found the following description of the Hot Rod Deluxe’s flabby-bass problem and the simple mod that fixes it. The following except is the midrange tone pot mod from the ‘James Vanden Berg Mods’ on the ‘Unofficial Fender Hot Rod Deluxe’ site:
(Remember the excerpt below is talking about the Hot Rod Deluxe…It seems almost as if they are describing the bass on the Lonestar!)
TONE CONTROL MODIFICATION TO BETTER CONTROL BASS RESPONSE
Why does this amp sound so flabby in the low end? Part of the reason lies in the speaker/cabinet combination. I’ve plugged this amp into other speakers to compare and found that the stock speaker/enclosure seems to really favor the bottom end, particularly for a 1-12 combo. This is great, because it means that the speaker and cabinet are very efficient for these critical lows, and if we can control the amount of bottom end the amp sends to the speaker, we can get great volume without working the amp too hard. The problem lies in the tone control section. I compared this circuit with other vintage Fenders, and the most critical difference is in the way that the Midrange control is wired. If you look at most of the older 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.
The Mid control on this amp is a 25kA pot. (“A” stands for audio taper). Thus, the stock circuit in this amp puts 25,000 ohms at all times between the bottom of the bass control and ground. On vintage Fenders without a mid control, the resistor in its place was usually only 6.8k. On models with a mid control, such as the Twin Reverb, the pot was only 10k, so even with the mid turned up all the way, it didn’t have the same low-end response as the stock circuit in this HR Deluxe. The larger the value of this midrange resistor, the more bass and low-mid the amp has, regardless of the setting of the bass control.
Have you ever seen a “Loudness” switch on an older stereo? The Loudness circuit boosts the bass and treble and is intended for low-volume situations to compensate for the fact that the human ear hears midrange frequencies (where most speech resides) more acutely at low levels than deep lows or high trebles. As volume increases, this effect reduces. If you play a stereo at high volume with the Loudness switch engaged, it can sound flabby because the bass frequencies are now over-amplified for our ears. This is precisely what’s happening with this Fender HR Deluxe. It sounds great at low levels, but the bass overwhelms the tone at higher volumes.
Justin's comments: Instead of using wire I took a small piece of solder and melted it into place. This creates a very unobtrusive jumper that's easy to remove. Be sure to test your jumper with an ohm meter to make sure it passes current.
Fixing this takes very little effort:
Follow steps 1 and 2 above. Solder a jumper between the left and middle terminals of the mid control (when facing the amp from the rear, as you would be when working on it). That’s it. You can now reverse steps 1 and 2 and try it out. If you did it right, you should now be able to turn your volume down to 0 by turning all of your tone controls to 0. More importantly, you can now dial in just the right amount of low end with the mid and Bass controls. Remember, they’re interactive. The higher you set the mid control, the more bass you will get.
END of Fender Hot Rod Deluxe MOD excerpt.
NOW BELOW: THE RESULTS I OBTAINED ON MY Fender Hot Rod Deluxe AND MY Mesa Boogie Lonestar:
Well I tried the mod on my Fender Hot Rod Deluxe…and it worked…very-very well
So, I started wondering if the Lonestar would benefit from a similar mod…and... could a Lonestar even be modded that way? Finally a few days ago I opened up my LSC Head and checked out the ‘midrange’ pots.
On the Fender HRD mod; the center contact on the pot is jumpered to the contact on the left. That is because on the HRD; the pot is mounted to the circuit board from the top…upside down… (So the contacts are facing down).
The Lonestar has ‘flying-leads’ and the pots are mounted with the contacts facing upwards. So with the Lonestar…I needed to run a ‘jumper-wire’ on the midrange controls on both channels FROM THE CENTER CONTACT TO THE CONTACT ON THE RIGHT. This has got to be the easiest ‘mod’ I’ve ever done! It is necessary (on the Lonestar) to do it to 2 midrange pots (unlike the HRD which has only one midrange)…but it was still easier because I had to partially remove the circuit-board from the HRD in order to do the mod on it.
I REPEAT: All the mod involves with the Lonestar is soldering a ‘jumper-wire’ from the middle contact of each midrange control to the contact on the right. (The middle and right when viewed from the back of the amp)
With the Lonestar; I only had to remove the midrange pot for Channel-1 in order to gain access to the pot on Channel-2… by being very careful I didn’t have to remove the Channel-2 pot. I carefully heated the center contact with my soldering-iron and pressed a very slim wire into the hole next to the gray wire already there. The contact on the far right has nothing soldered onto it; so there was no problem at all soldering the ‘jumper’ wire to it. Once Channel-2 was done; I put Channel-1’s midrange pot back in and soldered the ‘jumper-wire’ to it. I reassembled the amp and proceeded to try it out.
Wonderful ‘tight’ bass! There is still plenty of bass on tap…but it doesn’t ‘muddy-up’ the other frequencies and it retains definition longer even with the gain up. I A/Bd the modded head against my LSC Combo to make sure I was really hearing the dramatic improvement that I thought I was. It was a definite improvement. Within the hour I had modded the combo too.
Stock; the Lonestar almost seems to be pushing some ‘sub-bass’ with very low frequencies that are almost inaudible…and that bass seems to ‘leech’ power from other notes as well as ‘bottoming-out/muddying’ the audible low notes. This mod seems especially useful when turning up the gain on channel-2…but it definitely helps both channels. Don’t worry…the LSC still retains PLENTY OF BASS!
NOTE: I had serious doubts about whether this mod would actually do anything useful for the Lonestar…so I ‘hedged-my-bets’ and used long sections of wire with ‘dpt’ mini-toggle-switches attached for the test on the first Lonestar. That way if I didn’t like the effect of the ‘mod’ I could merely ‘turn it off’…without having to immediately tear the amp down to remove it. I let the wires with the switch ‘dangle’ out of the chassis for the test. Now, I can either remove the toggle-switches or find a good place to mount them…when I feel like it. I may actually keep the toggle switches in the circuit as that gives some more versatility. You could do the mod with toggle-switches attached too...in case you are unsure about whether you will like the mod. Then by 'flipping the switch' you can conduct your own A/B comparison test.
REMEMBER: Always be super careful when doing ANY work inside an amplifier! Dangerous High Voltages Inside! If doubtful get a professional involved!
I don’t know if ‘flabby/muddy’ bass’ is an issue with you or not; so I don’t know if you will be motivated to try the mod,…but I figured I’d tell you about it as a possible solution. YOU decide if you need or want it…based upon YOUR experience with the amp…NOT MINE or anyone else’s.
Cheers: Charles
