It Sucks To Be Right/dsl40cr!

[coyote]

While the 40C is not without its problems (noisy), I’m very glad I got it when I did. Else I’d likely have one of these 40CR units with all these switching issues.

What I really wish is that tubes were of high quality like in the old days. My Major worked well for years at a time before it would need the tubes changed out. Now you can’t go 18 months before the tubes start flaking out.

 

[matttornado]

So I been gigging with my new 1/18 build DSL 40CR all summer, maybe 7 or 8 shows. As I mentioned previously, I noticed that every once in a while, it would change the master I had each channel assigned to. I would have to go and re-assign the master for the channel I was on.

I also noticed that I would accidentally step on both switches on the foot switch while playing.

Last night while I was playing around, I learned that whenever I step on both the channel select & FX loop switch at the same on the footswtich, it cause the master volume select loose its assigned channel.

I am building a single footswitch now that only activates the channel select leaving the FX loop on.

Hopefully that's all it is. me stepping on both switches by accident.

Also, I finally measured the bias and plate voltage.

Amp as received the bias was set at 31 & 32 MV with a plate voltage of 430 volts. I tried to turn the bias up to about 38mV but the bias adjustment maxed out at 36 mV.

I'm hoping with a different set of output tubes, I'll be able to get the bias closer to around 40mV?

 

[Justin Whitstine]

I noticed the same thing when stepping on both footswitches at the same time. I wanted a boost AND the delay pedal in my fx loop to kick in simultaneously for a solo. And just like you, the amp lost its master volume assignment, so instead of a boost, my volume just disappeared. :\

Recently I put a Mxr 10 band EQ pedal in my fx loop for a boost, when I step on the fx loop footswitch.

Eventually I'll probably try controlling the amp with midi. But that is unfortunate as I just need a very simple footswitch. The stock footswitch is actually perfect for my needs, BUT I WANT IT TO WORK CORRECTLY!

 

[Chris-in-LA]

So I been gigging with my new 1/18 build DSL 40CR all summer, maybe 7 or 8 shows. As I mentioned previously, I noticed that every once in a while, it would change the master I had each channel assigned to. I would have to go and re-assign the master for the channel I was on.

I also noticed that I would accidentally step on both switches on the foot switch while playing.

Last night while I was playing around, I learned that whenever I step on both the channel select & FX loop switch at the same on the footswtich, it cause the master volume select loose its assigned channel.

I am building a single footswitch now that only activates the channel select leaving the FX loop on.

Hopefully that's all it is. me stepping on both switches by accident.

Also, I finally measured the bias and plate voltage.

Amp as received the bias was set at 31 & 32 MV with a plate voltage of 430 volts. I tried to turn the bias up to about 38mV but the bias adjustment maxed out at 36 mV.

I'm hoping with a different set of output tubes, I'll be able to get the bias closer to around 40mV?

Don’t waste your time buying new power tubes to increase the bias to 40 MV. Your problem is that there is too much resistance in your bias circuit, you need to change a resistor. My 2204 clone is doing the same thing, I started with low resistance and the bias went to 75 and would not go below 45. I put in another resistor with a higher value and now it only goes up to 36. Just play it, the difference between 35mv and 40mv is probably negligible.

 

[matttornado]

Don’t waste your time buying new power tubes to increase the bias to 40 MV. Your problem is that there is too much resistance in your bias circuit, you need to change a resistor. My 2204 clone is doing the same thing, I started with low resistance and the bias went to 75 and would not go below 45. I put in another resistor with a higher value and now it only goes up to 36. Just play it, the difference between 35mv and 40mv is probably negligible.

Yep I agree! It sounds great so as long as the tubes are not biased too high, I'm good.

 

[Gene Ballzz]

Eventually I'll probably try controlling the amp with midi. But that is unfortunate as I just need a very simple footswitch. The stock footswitch is actually perfect for my needs, BUT I WANT IT TO WORK CORRECTLY!

Imagine that! Expecting a brand new amplifier to actually work as intended? Now that's just being unreasonable! I have shared your pain, but all has been good for the three weeks since the amp came back from the Marshall Service Center at US Music Corp!

Still Switchin'
Gene

 

[DonP]

This is not a 50 watt amp. You guys are trying to bias a 40 watt amp to 50 watt levels are going to run too much current through the OT and fry it. Thank goodness Marshall limited the bias range.

 

[Justin Whitstine]

Imagine that! Expecting a brand new amplifier to actually work as intended? Now that's just being unreasonable! I have shared your pain, but all has been good for the three weeks since the amp came back from the Marshall Service Center at US Music Corp!

Still Switchin'
Gene

Gene,
Do you know what they did to it to solve the issue?
@Gene Ballzz

 

[matttornado]

This is not a 50 watt amp. You guys are trying to bias a 40 watt amp to 50 watt levels are going to run too much current through the OT and fry it. Thank goodness Marshall limited the bias range.

Interesting! no one that I know of mentioned that before. So each tube should be rated at 20 watts when calculating bias?

So my bias was good at factory settings of ~31 - 32 mA with B+ @ 430 VDC?

 

[Chris-in-LA]

Interesting! no one that I know of mentioned that before. So each tube should be rated at 20 watts when calculating bias?

So my bias was good at factory settings of ~31 - 32 mA with B+ @ 430 VDC?

Yes, if that is 430v plate voltage and the tube is rated at 20 watts.

 

[Gene Ballzz]

Gene,
Do you know what they did to it to solve the issue?
@Gene Ballzz

They told me that they tracked it down to a programming error in a chip, Though I'm not sure that I'm believing that! Mine would work perfectly until fully warmed up and then the issues would start. I don't see how a programming error could be relating to the warming up the amp. FWIW, I've left the amp fully on, in 40 watt "run" mode for several days and not yet had the problems return?

Just My $.02,
Gene

 

[Sir Don]

I'm still waiting on the 6 button footswitch.

 

[lovehifi]

I biased mine to 32-33ma and that is where it sounds the best to me. Mine came out of the box at 40ish ma. Too hot with fizzy gain.

 

[Snowdogyyz]

The 6 button footswitch makes the amp even better- like having a 4 channel amp (minus eq for all channels). It still has that slight hesitation when switching. Not an issue for me but could be for some. I’m having zero noise issues so far. Loving this amp!

 

[jcourtjr j]

Just got mine today. Got the fx loop footswitch problem, exactly as described here. I contacted Marshall support to see what they will do? Don't want to get rid of it because it sounds GREAT.

 

[Sir Don]

I'm glad mine doesn't have any noise issues or switching issues with the 2 button switch. I really like the sound.

 

[Wolvieberzerker]

Anyone know if the 100hr are doing this? Really like the tone and feel through a cab.

 

[jcourtjr j]

So I bought from musiciansfriend. I sent email to marshall uk? Is everyone just returning them?
I see Gene was succesful in getting his fixed. Anyone else go this route?

 

[Gene Ballzz]

Well here is how I started, after first contacting my vendor, Sweetwater, who has been great throughout the ordeal! Here is the email to Marshall in Bletchley, a re-send, the response and then my reply and another response from them. As you can see, I hadd to jump up & down a bit to actually get their attention! My contact at USMC was Kevin Drury at this email: marshall.service@USMusicCorp.com

"Hi Diana,

Thank you for your response. It would behoove you to actually read my message and/or forward it to someone technically and authoritatively advanced enough to see the importance of what is actually going on. This is an ongoing and rapidly escalating problem with one of your most popular and best selling products. If this is not addressed in a proper and timely manner, it will grow into a full blown and enormously expensive recall of this product! I am a huge and avid fan of Marshall’s amplifiers and have been for more than 40 years! I am sincerely hoping to help your company stave off a problem that could quite easily be costly enough to put the company out of business!
Please understand that what I’m looking for is an official corporate response, answer and solution to my enquiries, as opposed to a retail/marketing response for simply replacing my defective Marshall amplifier! While I’ll be more than pleased to hear from your US representative, the real solution for me and for your company will come at the corporate level! I am not just an angry customer! I am someone who actually cares about what happens to and with your company!
For what it’s worth, the vendor I purchased this from, pulled another identical unit, fresh from a sealed box and it exhibited similar issues! This is an issue that needs to be escalated quickly!
This Is A Serious Issue!
Gene Salvaterra

On Jul 12, 2018, at 7:35 AM, Contact at Marshall.com <contactus@marshall.com> wrote:

Good afternoon Gene,
I confirm receipt of your e-mail I have sent this to our customer support in the US.
They will respond within 48 hours
Best regards
Diana
CONTACT AT MARSHALL.COM
+44 (0)1908 375 411
DENBIGH ROAD, BLETCHLEY, ENGLAND, MK1 1DQ

From: Gene Salvaterra <XXXXXXXXXXXx>
Sent: 12 July 2018 15:30
To: Contact at Marshall.com <contactus@marshall.com>
Subject: DSL40CR/SERIAL # XXXXXXX 01-18
Hi Folks,
I’m sending this again, just in case it did not make it to you yesterday. I’ve received no reply or confirmation of you seeing it.
Thank You Again,
Gene Salvaterra
Good Day Folks,
I purchased this amplifier from Sweetwater and am contacting you in hopes of avoiding the roller coaster ride of having the vendor ship, return ship and re-ship, etc, etc, until I get one that functions properly!
Here are the purchase details:
Model: DSL40CR
Serial # XXXXXXXXXXX 01-18
SWEETWATER
Ordered: 06/29/2018
Invoice # XXXXXXXX
Received: 07/09/2018
Being an avid internet forum user, I’ve noticed a fair number of problems with this amp model. Some of them exhibit noise issues, but the majority of the complaints surround anomalies in the switching system. I’m fairly certain Marshall is aware of these issues and I’m hoping that they have already been addressed through production and/or design changes. I have been building and repairing amplifiers (as well as playing/using them) for more than 40 years and can generally surmise what the problem is caused by. Given your company’s propensity to keep schematic drawings as closely guarded secrets, this set of problems that could likely be easily repaired is beyond me!
Here is clear description of the issues I’ve encountered, though it should be noted that this particular unit, otherwise sounds fantastic and does not exhibit any of the noise issues that other folks have encountered:
> Everything in the switching system works perfectly and functions just as it should when the amp is first turned on.
> After the amp has been on for ten minutes or so, the effects loop can be turned off via the foot switch, but will not turn back on. This only occurs when using the CLASSIC channel. The loop LED on the pedal illuminates, but the loop does not activate! Also, just before the loop starts to not be able to be switched back on via the foot switch, it starts to develop a delay when switching on.
> If the loop is left on (according to the foot switch) and I toggle to ULTRA channel and back to CLASSIC channel, the loop comes back on, but will not come back on if switched off.
> At the same time that the loop problem comes up, the system decides to "forget" which MASTER is selected for the CLASSIC channel.
> It should be noted that all switching also functions perfectly when amp is in STANDBY mode, as well as after the amp has been turned off and allowed to cool down for a while!
> It should also be noted that everything functions as it should from the front panel switches, when the foot switch is unplugged!
> As I also have a DSL20CR, I have two of the same foot switches and the amp functions "exactly" the same with both of them, so it's a reasonable assumption that the switch itself is not the issue!


One intention of this email is hoping that IF this set of issues has already been addressed and/or corrected, that you may let me know after which manufacture date I can look for to avoid future issues? The other intention is as a friendly heads up from a long standing, loyal customer that if these issues have NOT been addressed, it will likely cost your company massive amounts of money in warranties and returns! Again, in case you are unaware, I have read of at least a hundred or more instances of similar, yet slightly different switching issues with this DSL40CR amp model as well as the DSL100HR!


Please let me know the best way to proceed from here! Should you choose to ship me a fully tested, perfectly functioning unit that would be fine also!


All of my contact information:


Gene Salvaterra
XXXXXXXXX
XXXXXXXXX
USA
Phone: XXXXXXXXXX


Thank You,
Gene Salvaterra"

 

[Gene Ballzz]

Oh, and FWIW, USMC said that mine was they first they had heard of or encountered this problem, but I'm not buyin' it!
Just My $.02,
Gene