DLS 100 with Mercury Magentics Transformer

jamesbreese · 07-01-2009, 11:14 AM

Well I just got done upgrading my DSL 100. I was having issues with cruddy sound. My amp would sound good for about the first 10 mins or so, and then get muddy and sounding like garbage. I had tried everything. New preamp tubes, new power tubes, new speaker leads. Nothing seemed to work. I read on the forum about bad Output transformers so I guessed it could be that, and even if it wasn't it was sure to improve on my sound.

Well it's installed. It was pretty easy, and if you have ever thought about replacing your transformer I can tell you it's worth it. My amp sounds AMAZING now. At all volume levels, with or without an attenuator.

Go Mercury!!!!

MartyStrat54 · 07-01-2009, 03:51 PM

Yeah, I hear a MM Output Tranny is the way to go. I'm glad that it cleared up your problem and better yet, gave you a richer sound.

Hey, did you ever check out the Brandon Clark band I told you about?

Marty

Jesstaa · 07-01-2009, 08:40 PM

Would mixing a MM OT with a Marshall stock PT give me a bad tone/cut down the awesomeness of the MM tranny, or does it still sound great? Because I can't really afford 2 new trannys plus shipping.

MartyStrat54 · 07-01-2009, 09:19 PM

It's amazing how much money you can spend on an MM PWR,OPT and Choke. To answer your question, just installing a OPT will make a big difference over the OE unit.

Marty

Jesstaa · 07-01-2009, 09:27 PM

Sweet, looks like the first thing on my agenda once I get a job, is get a new Mercury OT tranny, can't wait =P

And I'll have to get EL34s happening in my 900.

Btw, TS, you should get some clips up of your amp with the new Mercury tranny in it.

jamesbreese · 07-01-2009, 11:32 PM

Quote:

Originally Posted by MartyStrat54

Yeah, I hear a MM Output Tranny is the way to go. I'm glad that it cleared up your problem and better yet, gave you a richer sound.

Hey, did you ever check out the Brandon Clark band I told you about?

Marty

I sure did. Good rockin. I saw their myspace page, and I have seen that logo of their somewhere. Maybe Guitar Center.

But yeah this transformer is amazing.

jamesbreese · 07-01-2009, 11:43 PM

I dont think it will make much of a difference. I played with a Variac in front of my amp for a while and it didnt seem to make a difference in tone at all. I am sure it was probably doing things with the internals, but nothing amazing happened. With the new OT though... the difference is WOW. It sounds like heaven.

The install was pretty easy. The clip on things for the new OT were too big, so I had to solder (spelling?) the wires to it, but it was super easy.

solarburnDSL50 · 07-02-2009, 12:28 PM

Quote:

Originally Posted by jamesbreese

Well I just got done upgrading my DSL 100. I was having issues with cruddy sound. My amp would sound good for about the first 10 mins or so, and then get muddy and sounding like garbage. I had tried everything. New preamp tubes, new power tubes, new speaker leads. Nothing seemed to work. I read on the forum about bad Output transformers so I guessed it could be that, and even if it wasn't it was sure to improve on my sound.

Well it's installed. It was pretty easy, and if you have ever thought about replacing your transformer I can tell you it's worth it. My amp sounds AMAZING now. At all volume levels, with or without an attenuator.

Go Mercury!!!!

I feel a worth while upgrade on mine too. I would prolly take a pass on the choke if I had to do it again. I like a little sag in my tone and a choke I think tightens that up.

Keep that in mind if you ever consider going for a choke too. If you want tight like metal players would then I'd get a choke. Me, I'm a blues/rock player so a bit of sag to me is sexy.

MartyStrat54 · 07-02-2009, 07:08 PM

Yeah Joe, we all like sexy!

Marty

Jesstaa · 07-03-2009, 05:52 AM

Quote:

Originally Posted by solarburnDSL50

I feel a worth while upgrade on mine too. I would prolly take a pass on the choke if I had to do it again. I like a little sag in my tone and a choke I think tightens that up.

Keep that in mind if you ever consider going for a choke too. If you want tight like metal players would then I'd get a choke. Me, I'm a blues/rock player so a bit of sag to me is sexy.

This may sound like a fair bit of a nooby question, but what's the choke? I wanna upgrade my JCM 900 once I get the money so I can really let it roar, and I like a nice tight sound.

PaoloJM · 07-03-2009, 07:45 AM

Quote:

Originally Posted by Jesstaa

This may sound like a fair bit of a nooby question, but what's the choke? I wanna upgrade my JCM 900 once I get the money so I can really let it roar, and I like a nice tight sound.

A "choke" is an inductor. It has a low DC resistance and a high AC impedance.
A choke mod replaces the standard power resistor that some amps use.
The result of this is a more stable/solid screen and preamp voltage and much less sagging. The resistor will cause a voltage drop proportional to the current through it, this is what causes the sag while you play. The choke will not do this.
This results in a much tighter sound, and is great for modern rock.
I find the sag of the power resistor works really well for blues and classic rock.

The high AC impedance of the choke also reduces the buzz when playing at high gain levels.

The 900 would benefit from this mod if you play more modern, heavier rock/metal.

solarburnDSL50 · 07-03-2009, 08:36 AM

Quote:

Originally Posted by PaoloJM

A "choke" is an inductor. It has a low DC resistance and a high AC impedance.
A choke mod replaces the standard power resistor that some amps use.
The result of this is a more stable/solid screen and preamp voltage and much less sagging. The resistor will cause a voltage drop proportional to the current through it, this is what causes the sag while you play. The choke will not do this.
This results in a much tighter sound, and is great for modern rock.
I find the sag of the power resistor works really well for blues and classic rock.

The high AC impedance of the choke also reduces the buzz when playing at high gain levels.

The 900 would benefit from this mod if you play more modern, heavier rock/metal.

All of this and especially this.

jcmjmp · 07-03-2009, 09:10 AM

Quote:

Originally Posted by PaoloJM

This results in a much tighter sound, and is great for modern rock.
I find the sag of the power resistor works really well for blues and classic rock.

But at the same time, most of the vintage, classic amps all had chokes.

PaoloJM · 07-03-2009, 09:16 AM

Quote:

Originally Posted by jcmjmp

But at the same time, most of the vintage, classic amps all had chokes.

Most of the earlier amps used valve rectifiers which introduce that same sag feel, exept they do it for the power valves too, so it has an even greater effect/affect (never sure which, so there's both!!).
Valve rectifiers have an internal resistance, using around 100/200 ohms depending on the type, and drop voltage proportional to the current drawn just the same.

If the vintage amps had used a power resistor choke and a vlave rectifier the amp would have sagged like old ladies boobs!!

solarburnDSL50 · 07-03-2009, 09:19 AM

Quote:

Originally Posted by jcmjmp

But at the same time, most of the vintage, classic amps all had chokes.

Interesting point...

I swear mine lost sag after the choke. Oh well I still love the amp.

solarburnDSL50 · 07-03-2009, 09:22 AM

Quote:

Originally Posted by PaoloJM

Most of the earlier amps used valve rectifiers which introduce that same sag feel, exept they do it for the power valves too.
Valve rectifiers have an internal resistance, using around 100/200 ohms depending on the type, and drop voltage proportional to the current drawn just the same.

If the vintage amps had used a power resistor choke and a vlave rectifier the amp would have sagged like old ladies boobs!!

Ok...I'm learn'n here. I didn't see your post until I was done writing mine hehe.

No saggy boobies man.

jcmjmp · 07-03-2009, 10:09 AM

Quote:

Originally Posted by PaoloJM

Most of the earlier amps used valve rectifiers which introduce that same sag feel, exept they do it for the power valves too, so it has an even greater effect/affect (never sure which, so there's both!!).
Valve rectifiers have an internal resistance, using around 100/200 ohms depending on the type, and drop voltage proportional to the current drawn just the same.

If the vintage amps had used a power resistor choke and a vlave rectifier the amp would have sagged like old ladies boobs!!

JCM 800 and 1959/1987 both had solid state rectifiers AND a choke. The choke contributes to limiting sag but not in the same way as a rectifier or filter capacitors. The chokes attempts to keep the current steady. That's not the same thing as what the rectifier or filter caps try to do.

Voltage sag can contribute to the overall compression of the amp at high volume. A proper choke will keep current demand high, which in turn can contribute to sag wen the amp is pushed hard.

Jesstaa · 07-03-2009, 10:28 AM

Is it possible to mod in a switchable choke? Cause that'd be brutal.

solarburnDSL50 · 07-03-2009, 10:38 AM

Quote:

Originally Posted by Jesstaa

Is it possible to mod in a switchable choke? Cause that'd be brutal.

I like that idea.

PaoloJM · 07-03-2009, 10:40 AM

Quote:

Originally Posted by jcmjmp

JCM 800 and 1959/1987 both had solid state rectifiers AND a choke. The choke contributes to limiting sag but not in the same way as a rectifier or filter capacitors. The chokes attempts to keep the current steady. That's not the same thing as what the rectifier or filter caps try to do.

Voltage sag can contribute to the overall compression of the amp at high volume. A proper choke will keep current demand high, which in turn can contribute to sag wen the amp is pushed hard.

These amps are not known for their sag.
As I said, choke contributes to limiting sag/looseness in the screen and preamp. I've installed chokes into amps that previously used resistor chokes, and it's a big difference.
I also pointed out that a valve rectifier has a greater effect on sag as it contributes to the power valves as well, but I'm not sure what your point is here. Are you trying to say what I've said is incorrect?

You last sentence doesn't make sense?

solarburnDSL50 · 07-03-2009, 10:48 AM

Quote:

Originally Posted by PaoloJM

These amps are not known for their sag.
As I said, choke contributes to limiting sag/looseness in the screen and preamp. I've installed chokes into amps that previously used resistor chokes, and it's a big difference.
I also pointed out that a valve rectifier has a greater effect on sag as it contributes to the power valves as well, but I'm not sure what your point is here. Are you trying to say what I've said is incorrect?

You last sentence doesn't make sense?

Clear as mud his was. I'm thinking the choke diminishes sag and he is stating when the amp is pushed hard the choke will contribute to sag...?

Paolo describes what I found to be true with mine. I may have my choke removed and go back to how the amp was. Then it seemed to break out into musical feedback readily where now I really have to coax it into doing so and then it doesn't sing like it did. I don't know...

Something I have been thinking about for awhile now.

jcmjmp · 07-03-2009, 10:49 AM

Quote:

Originally Posted by PaoloJM

These amps are not known for their sag.
As I said, choke contributes to limiting sag/looseness in the screen and preamp. I've installed chokes into amps that previously used resistor chokes, and it's a big difference.
I also pointed out that a valve rectifier has a greater effect on sag as it contributes to the power valves as well, but I'm not sure what your point is here. Are you trying to say what I've said is incorrect?

You last sentence doesn't make sense?

I'm saying that you're partly right. By pulling more current out (via the choke) of the power supply, the voltage will drop. The choke doesn't drop voltage, it just demands the current that is needed and the changes in current demand are filtered by the choke. The dynamics of voltage sag with a choke vs a rectifier tube or reducing voltage filtering are not the same. That's what I'm saying.

A resistor is not a choke, its just a resistor.

You can still get some voltage sag with a choke but the dynamics of that sag are different when compared to sag that is due to lower power supply filtering, rectifier tube or a PT running at or over its limits. The sag will be tighter, if that makes any sense.

If you want sag, replace your filter caps to lower values like 32/32uf instead of 50/50uf

PaoloJM · 07-03-2009, 10:57 AM

Quote:

Originally Posted by jcmjmp

I'm saying that you're partly right. By pulling more current out (via the choke) of the power supply, the voltage will drop. The choke doesn't drop voltage, it just demands the current that is needed and the changes in current demand are filtered by the choke. The dynamics of voltage sag with a choke vs a rectifier tube or reducing voltage filtering are not the same. That's what I'm saying.

A resistor is not a choke, its just a resistor.

That's what I thought you meant.

A choke is not a load and does not demand current.
Valves demand current which flow from the power supply through the choke or power resistor. Chokes have a low DC resistance, usually lower than a power resistor, and so the voltage to the screens and preamp will be higher in the same amp
The dynamics of how sag happens with a power reswistor choke and valve rectifier are exactly the same; valves draw more current from the power supply which drops voltage across any resistance in it's path.
The only difference between the two is that the valve rectifiers sag affects the power valve plate voltage too, the choke or power resistor only affect the screens and preamp.

A power resistor in this position is performing the function of a choke. The word choke does not explicitly refer to an inductor, it refers to the function.

Jesstaa · 07-03-2009, 11:05 AM

Quote:

Originally Posted by solarburnDSL50

I like that idea.

It's a good idea, but is it feasible? If it is, I'm doing it. Lol.

solarburnDSL50 · 07-03-2009, 11:10 AM

Quote:

Originally Posted by Jesstaa

It's a good idea, but is it feasible? If it is, I'm doing it. Lol.

This is beyond me but if I could switch between both...I'd like that option.

PaoloJM · 07-03-2009, 11:11 AM

Quote:

Originally Posted by Jesstaa

It's a good idea, but is it feasible? If it is, I'm doing it. Lol.

Yep, it's easily do-able.
I was looking at implementing a inductor choke/standby/resistor choke using a single pole, double throw, centre off switch. You need a large Carling switch to do it. Some guys over at 18watt.com have already done it.

My next amp design will have a switch that changes resistor choke to inductor choke, removes the rectifier valve emulator resistor, while increasing the filtering, all at the same time to implement a vintage/modern power supply switch. This is possible by using a multi pole relay and a simple toggle switch.
I've already done the increased filtering and valve rectifier thing on the last amp I built and it work great, but they are seperate switches on that amp.

solarburnDSL50 · 07-03-2009, 11:16 AM

Quote:

Originally Posted by PaoloJM

Yep, it's easily do-able.
I was looking at implementing a inductor choke/standby/resistor choke using a single pole, double throw, centre off switch. You need a large Carling switch to do it. Some guys over at 18watt.com have already done it.

My next amp design will have a switch that changes resistor choke to inductor choke, removes the rectifier valve emulator resistor, while increasing the filtering, all at the same time to implement a vintage/modern power supply switch. This is possible by using a multi pole relay and a simple toggle switch.
I've already done the increased filtering and valve rectifier thing on the last amp I built and it work great, but they are seperate switches.

Right on man. Wished you lived next door to me hehe. I may have to run this by Jerry(FJA)and see if he would do this for me.

Thanks for the input Paolo!

jcmjmp · 07-03-2009, 11:18 AM

Quote:

Originally Posted by PaoloJM

That's what I thought you meant.

A choke is not a load and does not demand current.
Valves demand current which flow from the power supply through the choke or power resistor. Chokes have a low DC resistance, usually lower than a power resistor, and so the voltage to the screens and preamp will be higher in the same amp

Yup - My wording was wrong there. The choke does not demand current, it only filters it and when a change in current demand occurs, it opposes it (slows it down) somewhat.

With a resistor, when current demand increases, the voltage drop accross the resistor is greater compared to a choke, resulting in much larger and faster voltage sag.

Sag will be reduced with a choke for sure, but there will still be sag present in the amp.

Placing a resistor in place of a choke is not the same kind of sag that, say, a tube rectifier would yield because the dynanics would be vastly different.

I'm not sure what you mean by the choke affects the preamp. The choke is part of the B+ power supply. That has an effect on all tubes, not just the preamp, unless you're referring to a circuit that I am not familiar with.

PaoloJM · 07-03-2009, 11:23 AM

Quote:

Originally Posted by jcmjmp

Yup - My wording was wrong there. The choke does not demand current, it only filters it and when a change in current demand occurs, it opposes it (slows it down) somewhat.

With a resistor, when current demand increases, the voltage drop accross the resistor is greater compared to a choke, resulting in much larger and faster voltage sag.

Sag will be reduced with a choke for sure, but there will still be sag present in the amp.

Placing a resistor in place of a choke is not the same kind of sag that, say, a tube rectifier would yield because the dynanics would be vastly different.

I'm not sure what you mean by the choke affects the preamp. The choke is part of the B+ power supply. That has an effect on all tubes, not just the preamp, unless you're referring to a circuit that I am not familiar with.

Nope the choke is only part of the filtering for the power valve screens and preamp. The plate supply for the power valves, B+, is taken straight from the main filter cap in 99.999999% of guitar amps, not just Marshalls.

As I described above the sag dynamics/mechanisms are the same, just that the valve rectifier affects the power valve plate voltage as well.

jcmjmp · 07-03-2009, 11:27 AM

Quote:

Originally Posted by PaoloJM

Nope the choke is only part of the filtering for the power valve screens and preamp. The plate supply for the power valves, B+, is taken straight from the main filter cap in 99.999999% of guitar amps, not just Marshalls.

As I described above the sag dynamics/mechanisms are the same, just that the valve rectifier affects the power valve plate voltage as well.

Again.... maybe I wrote too quickly. My point was that it affects all tubes, not just the preamp.

07-01-2009, 11:14 AM	#1 (permalink)
jamesbreese Junior Member Join Date: Feb 2009 Location: Tulsa, Ok Posts: 12	DLS 100 with Mercury Magentics Transformer Well I just got done upgrading my DSL 100. I was having issues with cruddy sound. My amp would sound good for about the first 10 mins or so, and then get muddy and sounding like garbage. I had tried everything. New preamp tubes, new power tubes, new speaker leads. Nothing seemed to work. I read on the forum about bad Output transformers so I guessed it could be that, and even if it wasn't it was sure to improve on my sound. Well it's installed. It was pretty easy, and if you have ever thought about replacing your transformer I can tell you it's worth it. My amp sounds AMAZING now. At all volume levels, with or without an attenuator. Go Mercury!!!! __________________ J. Breese Tulsa, OK JCM2000 DSL 100 1960A 30 Watt Celestions 1960B 75 Watt Celestions

07-01-2009, 03:51 PM	#2 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,583	Re: DLS 100 with Mercury Magentics Transformer Yeah, I hear a MM Output Tranny is the way to go. I'm glad that it cleared up your problem and better yet, gave you a richer sound. Hey, did you ever check out the Brandon Clark band I told you about? Marty __________________ MARTY 2009 Gibson Explorer-Hell Raising Machine 1989 Fender Strat Plus USA 2008 Fender Tele USA 2004 Schecter Elite w/DiMarzio's TSL100 with custom 4x12 cab. TSL122 with Man 'O War Speakers. TSL602 #1 with JBL D123 Speakers and 602 #2 with Altec 417 Speakers. "Oh so sweet my friends." DSL401 #1 with Red Fang Speaker and 401 #2 with JBL D123 Speaker. Tubes: Let's just say they are NOS that kick ass.

07-01-2009, 08:40 PM	#3 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 797	Re: DLS 100 with Mercury Magentics Transformer Would mixing a MM OT with a Marshall stock PT give me a bad tone/cut down the awesomeness of the MM tranny, or does it still sound great? Because I can't really afford 2 new trannys plus shipping. __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Sovtek 7025 Pre: V1 - N.O.S Mullard ECC83. V2 National 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

07-01-2009, 09:19 PM	#4 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,583	Re: DLS 100 with Mercury Magentics Transformer It's amazing how much money you can spend on an MM PWR,OPT and Choke. To answer your question, just installing a OPT will make a big difference over the OE unit. Marty __________________ MARTY 2009 Gibson Explorer-Hell Raising Machine 1989 Fender Strat Plus USA 2008 Fender Tele USA 2004 Schecter Elite w/DiMarzio's TSL100 with custom 4x12 cab. TSL122 with Man 'O War Speakers. TSL602 #1 with JBL D123 Speakers and 602 #2 with Altec 417 Speakers. "Oh so sweet my friends." DSL401 #1 with Red Fang Speaker and 401 #2 with JBL D123 Speaker. Tubes: Let's just say they are NOS that kick ass.

07-01-2009, 09:27 PM	#5 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 797	Re: DLS 100 with Mercury Magentics Transformer Sweet, looks like the first thing on my agenda once I get a job, is get a new Mercury OT tranny, can't wait =P And I'll have to get EL34s happening in my 900. Btw, TS, you should get some clips up of your amp with the new Mercury tranny in it. __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Sovtek 7025 Pre: V1 - N.O.S Mullard ECC83. V2 National 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

07-01-2009, 11:43 PM	#7 (permalink)
jamesbreese Junior Member Join Date: Feb 2009 Location: Tulsa, Ok Posts: 12	Re: DLS 100 with Mercury Magentics Transformer I dont think it will make much of a difference. I played with a Variac in front of my amp for a while and it didnt seem to make a difference in tone at all. I am sure it was probably doing things with the internals, but nothing amazing happened. With the new OT though... the difference is WOW. It sounds like heaven. The install was pretty easy. The clip on things for the new OT were too big, so I had to solder (spelling?) the wires to it, but it was super easy. __________________ J. Breese Tulsa, OK JCM2000 DSL 100 1960A 30 Watt Celestions 1960B 75 Watt Celestions

07-02-2009, 07:08 PM	#9 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,583	Re: DLS 100 with Mercury Magentics Transformer Yeah Joe, we all like sexy! Marty __________________ MARTY 2009 Gibson Explorer-Hell Raising Machine 1989 Fender Strat Plus USA 2008 Fender Tele USA 2004 Schecter Elite w/DiMarzio's TSL100 with custom 4x12 cab. TSL122 with Man 'O War Speakers. TSL602 #1 with JBL D123 Speakers and 602 #2 with Altec 417 Speakers. "Oh so sweet my friends." DSL401 #1 with Red Fang Speaker and 401 #2 with JBL D123 Speaker. Tubes: Let's just say they are NOS that kick ass.

07-03-2009, 10:28 AM	#18 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 797	Re: DLS 100 with Mercury Magentics Transformer Is it possible to mod in a switchable choke? Cause that'd be brutal. __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Sovtek 7025 Pre: V1 - N.O.S Mullard ECC83. V2 National 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

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