31

Gear Closet / Re: Marshall DSL15H project

« on: October 12, 2015, 04:40:17 PM »

Fixing the Red CH might be as simple as using a 12DW7 pre-amp tube in V1. The 12DW7 has a 12AX7 triode for the A triode ( pre-amp tubes are actually two tubes or triodes in one bottle) and a 12AU7 for triode B. A 12AU7 has only 1/5 the gain of the standard 12AX7. So if the Red Ch uses V1B, that will be a far easier fix that modding the printed circuit board.  Still need to up the gain of the Green Ch in that case, though, because the Green Ch sux if its master volume and gain are not dimed. If the Red Ch uses V1A then it won't affect the Red Ch and will totally gut the already gutless Green CH. 

32

Gear Closet / Re: Marshall DSL15H project

« on: October 12, 2015, 02:38:57 PM »

I can't seem to find any schematics for the DSL15 online.  Plenty of JCM2000  DSL schems but the boards and lay outs are different. That makes it it kind of a puzzle to find the components affecting the green channel.  The Red channel mods are well known.

The plate voltages are up around 425V,  which means I can't use old stock 6v6 tubes pulled from an old radio or something.  The max rating on old style 6V6s are 315v and 12 watts max dissipation.  Apparently new design 6V6s can handle up to 450 volts and have 14 watts max dissipation (and sound more 6L6 like).

33

Gear Closet / Re: Marshall DSL15H project

« on: October 09, 2015, 11:38:40 AM »

All the caps are the board. These caps are on the power amp, and the pre-amp derives its power supply from there through a resistor instead of a choke.

50 watt Marshalls have always used 50uf filter caps through out, including 50uf on both sides of the choke.  The original JTM45 only used 16uf . Many run a 32uf on the power amp side of JTM45s (including mine) to prevent ghosting.

The 100 watt circuits have general ran 100uf on the power amp side, and 50uf on both sides of the choke like the 50 watt, but there is quite a complicated history of the evolution of the filtering of the 100 watt amps. Early plexi 100s had low filtering (often ghosting) and then by about 69 they had high filtering.  Then in about 1986 they reduced the number of the filter caps on the 100s to make them easier to build.  A lot of people think that the pre 86 100 watt JCM800s have more punch.

Hiwatt 100s make an interesting comparision. Hiwatts ran 200uf on the power amp, 100uf on the screens, and 50uf on both sides of the choke. (BTW the Jubilee tone stack and taking the signal to the tone stack from the plate instead of the cathode are based on the Hiwatt amps design)

 Orange and Matamp ran 100uf  and only 16 uf on both sides of the choke.

Fender Tweeds ran about 20uf caps throughout. The Black Face Fender amps started running about 70uf on the power amp side which became more standard after the CBS take over going into the silver face era. By the 70s many Fenders were running 200uf on the power amp side.

34

Gear Closet / Re: Marshall DSL15H project

« on: October 08, 2015, 10:05:23 AM »

Thanks,

I took the chasis out and checked the bias before running it loud at my current loud playing space yesterday.  The bias was way out of whack.  One tube was dissipating 94% of max dissipation and the other was at 82%. I set them both to 70%.  It did improve the basic tone on both channels.  The green is much less boomy now, but still needs the gain on max to sound decent. The red is smoother but still fizzy. Gone was an annoying treble spike on the Red Channel.

While I had the amp apart, I noticed that the filter caps are 100uf.  This explains the stiffness of the amp. 50uf filter caps are on the list of things to try now.

Previous to the bias check I tried it in some different cabs with Vintage 30 speakers.

V30 1x12 open back-  It sounded better than through the 4x12 for the most part. The Red channel was boxy and a bit nasal, but the Green now wasn't boomy at all with the Deep Switch not engaged. This speaker is a 90s Mesa spec that doesn't have the infamous upper mid spike.

V30 large volume 1x12 closed back- Smoother yet and a little less boxy.  Solid lows without too much boom.

I also A/Bed the amp against some others of mine for reference tones.

Green CH vs MetroAmp JTM45- Should not have done this.  The DSL Green ch sounded like a transistor radio compared to the JTM45 run clean. 

Red Ch vs Silver Jubilee 50/25 watt. I expected this. The Jub completely destroyed the DSL's gain channel. The Jubilee gain channel just sings and is so 3d and dynamic. The Jubilee has not near the hiss and buzz when its not playing a note either. The DSL red Ch is real noisy.

Orange Micro Terror 20 watt.  Should not have tried this either.  The 1/2 solid state Orange sounded way more tubey and organic. And dynamic. Although the Orange only has three knobs you can set the gain knob up to about 3 O'clock and control the tone from your guitar volume. Turn your guitar down and the Orange cleans up (not completely of course) and crank the guitar volume on a humbucker and its a nice driving overdrive with out fizz. It is as loud as the DSL15.

At the rehersal space, which has high ceilings and hard wood floors and plenty of natural hall reverb, the DSL sounded pretty good. The fizz gets lost, for the most part, in the mix and also the woosh of the room.  You can still hear it but with the masters cranked up, you can hear the 6V6s starting to take over and overide the fizz and thinness.  Below 6 on the masters and it is noticably thinner. The triode mode cranked is good on both channels. I ran it through the V30  closed cab.

 

35

Gear Closet / Marshall DSL15H project

« on: October 07, 2015, 01:02:35 PM »

I have always liked the concept of a 6V6 Plexi, so when it became apparent that the DSL15H heads are availabe used for not a lot of money I snagged one with intention of modifying it.

The word on these amps was that the green channel is too clean and the red channel is too much gain. Well the DSL 15 watt only offers those two modes that nobody used on the old JCM2000 amps. What was the thinking here?  They probably expected the customer demographic for this amp to complain if the gain was not over the top, and the clean was not clean enough. The amp can be modded, but if your not into modding amps these amps are pretty much useless to players other than modern metal players in its stock form. I will be following the mods pioneered by the guys over at the Marshall Amp forum, and the My Les Paul Forum.  I hope nobody minds if I log the journey here.
 
First impressions:
 
 Not very loud.  Even through a 4x12 and cranked up it sounded not very loud.  There is no way this amp can be used with a live drummer at this volume level.  But then I noticed that the pentode-triode switch on the back was set to 1/2 power, or only 7.5 watts.
 
 In 15 watt mode it was totally different.  It can get loud. Exploring both channels through various knob settings and with both humbucker and single coil guitars revealed the following;
 
Green Channel. Way too clean and rather boring sounding.  I had to use the Green channel gain knob on ten at all times for it to have any character at all.  Turn it down to 9 and it became very weak and thin. I normally use PAFs and single coils and do not want to back to high output pickups.

There is a tone shift button that should never be used. It makes it sound like one of those 1970s Fender Twinns that we all hated. Even with the gain on ten the Green channel sounded "plinky".  It had no sustain.  Even more troubling, was that the bass notes were boomy through the Green Back loaded 4x12. It was a like a kick drum when ever a bass string was touched, especially with the Deep Switch engaged.  The Deep Switch was not usable with the 4x12 when using the Green Channel.

 Both the tone shift and the deep switches affect both the Green and Red channels.
 
Red Channel- What a fizzy mess! Bright, harsh, and fizzy, and waaaayyy too much gain. It is basically unusable. At least for me.  Even with the gain knob at only 9:00 it is too distorted. With very low gain settings the Red is still too distorted although thinner.  With low gain settings and the volume whacked up to ten, I think I can hear some mojo from the 6V6s under all that fizz. I think.
 
With the Green channel on ten/ten it is still too clean.  And boomy.
 
What I disliked most about the amp, though, was how stiff it both sounds and feels.  It does not breathe like a traditional tube amp at all. In fact despite the all tube signal path it feels almost solid state. Stiff and tight to the point of brittleness. The Red channel does not sing, and the Green channel is plinky sounding.
 
Many have modded the Red channel into something usable but left the Green channel alone. I will be modding both.
 
 
 
 
 

36

The Pickup Place / Re: T-Top and '59

« on: September 27, 2015, 08:41:34 PM »

I don't think there is one for either. Unless it's the Master set which I haven"t tried.

37

The Pickup Place / Re: Bridge n Middle to balance Injector Neck (HSS Strat)

« on: September 15, 2015, 10:00:21 AM »

The 36th handles gain well. It is articulate under high gain in a strat.

I have used various HSS guitars for years, and Dimarzio tech support is right about PAF types working best with singles or single voiced pickups in the neck and middle.  The original Fender Lone Star strat used a Pearly Gates Plus (a PAF clone).

There is a school of thought of using a high output humbucker with a stronger output while split with the middle pickup, and then having a much louder output when the humbucker is in-series.

But the 36th splits well and has pretty good output anyway. It's a good recommendation in my opinion.

When I tried the 36th in a strat it was a little too bright for me with 500k pots.  If the Injector requires 500k pots, I would probably use a 500k master volume and a 500k tone on the injector, with a 250k tone on the bridge humbucker.

38

The Pickup Place / Re: I'm like a throwback to 2006 - Looking for suggestions

« on: September 10, 2015, 02:13:31 PM »

The PG bridge is relatively hot for a PAF, and it is bright. It has some cut. I had to use 250k pots with a PG bridge on a strat.

 The PG neck is warm. The PG set are like opposites on the same guitar, and that provides for a wide range of possible tones from warm to bright.

39

The Pickup Place / Re: I'm like a throwback to 2006 - Looking for suggestions

« on: September 10, 2015, 11:04:32 AM »

You owe it to yourself to try the Air Classic.  There's not a more musical pickup made and its not too hot.

40

The Pickup Place / Re: neck match for Super D

« on: September 10, 2015, 11:01:03 AM »

While this is a somewhat old topic, it looks like we could use a little traffic and this topic interests me:

I don't use a neck pickup too often, but when i do it's for bluesier stuff ala Allman Bros. That creamy fat tone. Not muddy.

All the Brothers (Duane, Dickey, Warren, DDT, Derek, Jack, Jimmy...) used the neck pickup a fair bit for both leads and chords. Neck pickup use is a big part of the ABB sound. In most cases they are using a stock, and covered, PAF, in both positions. 

Even when Dickey uses a strat, which he does quite a bit, he uses the neck position with an unknown (to me) rail pickup there.  Jack Pearson also used rail pickups in his strats, although he often used the bridge position much more than the others.

It is reported that Dickey's rig can sound harsh and bright in the hands of others but as soon its in Dickey's hands the tone is warm and creamy. Another case of "tone is in the hands". To get closer to that creamy sound at less than arena volume, many of us could probably use a slightly stronger neck pickup, such as the Breed neck, or the PAF Pro.

Duane found a set of PAFs in one of his gold tops that he transferred to other guitars when he found a new number one. These probably had a bit more output needed for slide work.  It is said that he wasn't 100% happy with any guitar until he found a tobacco burst les paul in the last months of his life.

41

The Pickup Place / Re: Looking to try something between a 36th PAF and Tone Zone

« on: May 02, 2015, 03:09:05 PM »

Some other Dimarzio pickups with some PAF properties but more power to consider:

Breed neck
Liquifire

42

The Pickup Place / Re: Single coils for Trower and Gilmour tones

« on: May 02, 2015, 03:02:14 PM »

The standard Gimore pickup is the Duncan SSL-5, which is a hot single. 

A Blue Velvet may work for both, anyway, considering your amp.

Trower often uses a Fuzz Face type device between the strat and the amp. This approach lets you control the tone more with your guitar volume when using low output pickups. Cranked up it drives the fuzz face which in turn drives the amp harder, and backed off it cleans up. Trower for many years used a JCM 800. Now he uses a Vintage/Modern. With a Soldano you should not need either a fuzz or a loud pickup, just set your gain in a spot that allows you to clean up or push it.

You may want a noisless set with the high gain amp, though.

43

The Pickup Place / Re: HFH vs Super 2 vs 36th

« on: November 19, 2014, 10:15:00 AM »

I use the Bluesbucker as the neck pickup in my TZ loaded Charvel. Its a great neck pickup with a high output bridge humbucker. It has a lot more power and body than a traditional strat single coil but its much more clearer than most traditional neck humbuckers.

44

Everything you wanted to know about .... / Re: Air Classic

« on: October 30, 2014, 09:40:43 AM »

Thread revival it seems. I'm thinking of getting a matched set for my LTD Xtone PS-1. I'm looking for a more jazzy tone with this guitar. Dimarzio recommended the 36th anniversary PAF neck in the neck position, and the Air Classic bridge in the bridge position. Anyone willing to share some insight on that???

The 36th is bright and tight. The neck model even more than the bridge model. So they are recommending it for the neck position to maximize articulation in that guitar for how you want to use it.

The Air Classic is more musical and sweet so it will pay nicely in the bridge position for what you want.

45

The Pickup Place / Re: Old timers...Virtual Hot PAF vs 36th bridge?

« on: September 13, 2014, 10:31:39 AM »

As far as the 36th being as bright as the Pearly Gates, I would say yes. Bright and tight (for a PAF) is how I describe the 36th. The 36th in the Bridge is not thin though. As far as output, the 36th does have more than the avarage PAF but not quite as much as the Pearly Gates as I remember them. I would say the Pearly Gates compares more closely to the PAF Pro or the Fred in output. DiMarzio says that the 36th is as loud or louder as the VHPAF, but other say no its not.