madbeanpedals::forum

General => Open Discussion => Topic started by: culturejam on April 01, 2018, 04:24:24 AM

Title: NAD: Marshall DSL20HR
Post by: culturejam on April 01, 2018, 04:24:24 AM
I've actually had this for about two weeks now. Just wanted to wait to play it a few hours before I weighed in with an opinion on tone, features, etc.

Overall, I really like it. I'll break down what I see as the pros and cons:

PRO:
• Tons of gain on tap on the red channel, but it never gets fizzy.
• Low-end is very prominent but can be mostly dialed out if desired (Bass control + Resonance control)
• The tone stack is very responsive and works in a logical way
• Sounds *phenomenal* when cranked and *really really good* at lower volumes...this is all on the 20W mode
• It's 20W but still has EL34s, but it's cathode biased instead of fixed. So it's still got a "big bottle" sound about it without being a total beast watts-wise.
• Digital reverb is pretty decent. Better than a Belton brick, but not as good as a dedicated DSP pedal or rack unit.

CON:
• The green (clean) channel is what I would call "neither fish nor fowl". It can't ever get totally squeaky clean (with humbuckers anyway), but it also doesn't ever top out with a nice crunch. It goes from sorta-clean to not-quite-driven.
• In the 10W mode on the red channel, the same tone is mostly still there as 20W, but there is a fair loss of high end which requires an EQ adjustment to get it close to the 20W mode. Still, it's impressive and a noticeable volume reduction. I marked this a con because I had read many comments saying "it sounds exactly the same at 10W as 20W", but I'm just not hearing that.

Not tested yet: effects loop, emulated output jack.

Other notes:
• The EL34s are JJ brand and matched (see photos below). The silkscreen says Marshall, but the shape is a dead giveaway...as is the JJ logo sticker on the base. :) 
• The phase inverter appears to be Chinese, but V1 and V2 appear to be JJ as well. Silkscreen markings are identical to the EL34s, and I compared the internals to some JJ 12ax7s I have, and they look nearly identical (same getter, same plate size and configuration, etc).

Enough yapping. Here's some photos.

(https://i.imgur.com/rYTY5xE.jpg)


(https://i.imgur.com/Xg5diEv.jpg)


(https://i.imgur.com/cANx8wv.jpg)
Title: Re: NAD: Marshall DSL20HR
Post by: pickdropper on April 01, 2018, 12:32:56 PM
I've spent a lot of time playing old Marshalls lately and I find that I almost always have to knock the bass to 0.

I've only spent a little time with that amp, but it seems pretty cool.  I'd probably spend most of my time playing with the red channel.  If there is a high end loss with the 10W setting, I'd just stick on the 20W setting as it's only a 3dB volume cut to go down to half power (theoretically, at least).
Title: Re: NAD: Marshall DSL20HR
Post by: jimilee on April 01, 2018, 01:00:34 PM
Neat little box


Sent from my iPhone using Tapatalk
Title: Re: NAD: Marshall DSL20HR
Post by: culturejam on April 01, 2018, 01:18:38 PM
Quote from: pickdropper on April 01, 2018, 12:32:56 PM
If there is a high end loss with the 10W setting, I'd just stick on the 20W setting as it's only a 3dB volume cut to go down to half power (theoretically, at least).

Agreed. The 20W setting is easy enough to run at low master volume and still sounds good. I mainly brought up the 10W high loss because I had seen some guys on TGP claim that it sounded "exactly" the same in both modes. I do not agree.  ;)
Title: Re: NAD: Marshall DSL20HR
Post by: gordo on April 01, 2018, 10:31:29 PM
Nice little amp.  I like the fact that it's not running EL84's.  Nice sounding tubes but you just can't get the "grunt" out of the smaller bottles.
Title: Re: NAD: Marshall DSL20HR
Post by: culturejam on April 06, 2018, 03:21:16 AM
I decided that even though this is a cathode biased amp, I might as well check the current draw on the power tubes. I have one of those "bias probe" sockets with DMM leads I got ages ago and have never used (until tonight).

Maybe I'm using it wrong (but it seems like there's only one way?), but it looks like the one tube I checked is pulling 56mA in 20W mode.

Seems high, right? Like, an EL34 should be pulling 35mA - 40mA in most cases, from what I've read.

I had a speaker load attached, and a guitar plugged in to the input. I think I set it all up right.

Is the current draw different for cathode bias? Is it possible the reading is for both tubes? Obviously, I know fuck-all about how this stuff works.  ;D

(https://i.imgur.com/ArBbtvx.jpg?1)
Title: Re: NAD: Marshall DSL20HR
Post by: culturejam on April 06, 2018, 03:23:26 AM
And just for kicks, here's a gut shot:

(https://i.imgur.com/8HJr1jz.jpg?2)
Title: Re: NAD: Marshall DSL20HR
Post by: culturejam on April 13, 2018, 04:12:09 AM
I put the stock preamp tubes back in so I could test the stock JJ EL34 power tubes vs a set of JJ E34L tubes. As expected, it's not a night/day difference. But I could hear some differences.

The E34L tubes break up a little bit later than the stock tubes and the overall sustain on the dirty channel is slightly less. It's maybe a 10-15% difference, but it's enough to notice. I don't have golden ears, so if I notice it, it's probably really happening. :)

On the clean channel, there's not much difference other than the slightly less gain of the E34Ls, which to me is an improvement.

The other main thing I can hear is that the E34Ls have less hum/noise than the stock tubes. Again, not a "game changer" difference, but I noticed it.
Title: Re: NAD: Marshall DSL20HR
Post by: thesmokingman on April 13, 2018, 01:05:55 PM
going to keep this one in mind ... I have an 18 watt and there are two main things lacking there, master volume and an effects loop ... still eyeballing the or-15 too