Jump to content
Why become a member? ×

NAD - Burman MPA & SL100 Powerpak


discreet
 Share

Recommended Posts

[b]NAD - Burman MPA & SL100 Powerpak[/b]

After much experimentation with hybrid and solid-state amps, valve pre-amps, analog modelling preamps and pedals and just about every combination of box and sound-shaper apart from a proper valve pre used with a proper valve power amp, I decided that the only way to get the 'all-valve bounce' was to, er... get a proper valve pre and proper valve power amp.

And so I bought this Burman MPA preamp and Burman SL100 power amp on eBay. Hand-built by Greg Burman in Newcastle in 1972. Needless to say it didn't work properly. Damn you, eBay! :rolleyes:

However, a quick visit to Greg Michalik at Guitar Aid in Putney and all is well. A valve in the pre wasn't getting power for some reason and Greg fixed that. Then it was noted that the four valves in the power amp were not a matched quad set as they should be, so Greg fixed that, too. Thanks, Greg! [url="http://www.guitaraid.co.uk/"]http://www.guitaraid.co.uk/[/url]

Other non-standard mods include a PowerCON mains cable (as the old Bulgin original was pants) and two new speaker jack outputs, which were worn out to the stage where the speaker cable would just flop out of its own accord. Fnarr.

So... it's [i]very [/i]loud. It's very clean. It's chunky and bouncy, twangy, hefty and beefy. It's as loud as my B2000 and yet it's 'only' a 100W amp. It's quite true, valve watts are really [i]not [/i]the same as solid-state watts.

For a bit more grit I've jumped three of the four input channels and if you push the gains a bit this works very well indeed. It's the real thing. Basically the rig sounds brilliant just set flat and with the volume turned up. :) I'm in all-valve heaven at last.

Plus Burman kit is quite rare, very cool and built to an extremely high standard. What's not to like? Well I'll tell you... these two bits of kit together weigh 45 kg (99.2 lb). But... the noise it makes is definitely worth the hassle. Very happy! Big grin on face! :D

Inside the MPA... Mullardy goodness:



Inside the SL100 - new JJ EL34s:



Outside the MPA Pre:



Outside the SL100 Powerpak:



There's magic in them glowing bottles, I tells ya! :)

Edited by discreet
Link to comment
Share on other sites

[quote name='RandomBass' timestamp='1389988522' post='2340380']
Glad that worked out young man. General rehearsal and gig reports are now expected. Looks a great setup.
[/quote]

Thank you sir - first all-valve rehearsal on Monday evening, I will file a report. :)

[size=4][quote name='Marvin' timestamp='1390000279' post='2340531'][/size]Great that it's got that sound you've been hunting down.
[/quote]

Kind of knew it would be the all-valve thing, but have been unable to commit to a brand new (or even used) valve head... [size=4]they're not particularly affordable, as you know. This kit cost less than a quarter the price of a new SVT CL (for example) plus the tech work.[/size]

Edited by discreet
Link to comment
Share on other sites

[quote name='Roland Rock' timestamp='1390044343' post='2340781']
Superb! Are you playing through the BFM cabs?
[/quote]

Yes! I've also got bertbass's Carvin 8X10 on loan and it sounds terrific through that too, though different. I prefer [size=4]the BFM J12s, they offer a lot more clarity and detailed reproduction of valvey harmonic content it would seem... which is great, as they're a whole lot easier to haul. ;) Getting surprising amounts of low-end heft too, given their Hz specs on paper.[/size]

Edited by discreet
Link to comment
Share on other sites

Yes... thanks very much for those images, Jack. :lol:

Took the Burman rig and my newly-restored 1974 Hayman 4040 bass to rehearsal last night... in retrospect what I should have done was use the Burman stuff with my regular Custom P first - too many altered parameters meant I couldn't tell which part of the tone was due to the amp and which was due to the new bass - d'oh!

No matter, because the combination of the two was awesome... all-valve is definitely where I'm at tone-wise. Lots of thump and heft, yet the pitch of each note quite clear, the whole sitting perfectly in the mix. Very pleased. Lots of positive comments from the band too, which is good because they will generally use any excuse to blame me for their shortcomings. ;)

AND... I had some misgivings about whether 100W would be enough for rehearsal and/or gigs... needn't have worried. We rehearsed at our usual volume, i.e. not stupid loud, but fairly 'robust' - I had the input gains up at twelve o'clock and the master volume at 8 o'clock. [i]Loads [/i]of power in reserve - lots of headroom. Very difficult to make this amp break up, in fact. You just get lovely round warmth by pushing the gains and that's it. Perfect for my purposes. No hint of [size=4]uncontrolled distortion in any way, yet a shedful of creamy harmonic content. A real man's amp! Very pleased.[/size]

Hayman bass great too - very different from my P and more difficult to play - slab body, heavy, relatively high action, Fender flats, tuners not all they could be - BUT all worth it, because it sounds great with fingers for a solid and very rounded dub-style tone, or with a pick for a beefy, bouncy lo-mid rock twang. Huge amounts of sustain in either case. Used both split pickups simultaneously. A real man's bass! Again, very pleased.

Found myself playing fewer notes and leaving more space, which had the effect of stripping down the overall sound and making more sense of the material. The big, full-range tone meant I didn't feel the need to fly around the fretboard to make up for any perceived deficiencies.

Conclusion: Oh, yes. Can't wait to gig this gear. It's all I need. The early 70s is a good place to be, tone wise - IMHO.
If only I were a real man, all would be well. :D

Link to comment
Share on other sites

[quote name='discreet' timestamp='1390301922' post='2343671']
Very difficult to make this amp break up, in fact. You just get lovely round warmth by pushing the gains and that's it.
[/quote]

I've just discovered that if you bridge [i]all four[/i] inputs and have the gains up at 3 o'clock, you will be in gritty grindy country. :)

Edited by discreet
Link to comment
Share on other sites

Congrats!
Your write-up was certainly inspiring.
Though sadly it may mean BC loses its grumpy, negative, no-fun discreet now, and gets a boring happy one in return. I'm not sure I like Burman that much anymore. ;) :P :D

What's this input bridging about? Does it mean that each of them inputs only can supply a limited current to the pre? I'd always assumed that a gain knob wide open meant virtually 0 Ohm, but I must be wrong then? Or are there step ups in the mixer?

Anyway: have fun with it.

Link to comment
Share on other sites

[quote name='BassTractor' timestamp='1390313861' post='2343898']
Your write-up was certainly inspiring... ...What's this input bridging about? Does it mean that each of them inputs only can supply a limited current to the pre? I'd always assumed that a gain knob wide open meant virtually 0 Ohm, but I must be wrong then? Or are there step ups in the mixer?
[/quote]

Thank you - a bit [i]too [/i]inspiring, perhaps... and I know very little about the electronics of the MPA pre-amp except that it has four Mullard ECC83s in it, and when I bridge inputs 1 and 2 I get more signal, or gain, or whatever you want to call it, going into the power amp. Bridging all four with the gains up gives maximum beans and a grindy tone. No doubt one of our more technical members could explain it? :)

Edited by discreet
Link to comment
Share on other sites

[quote name='Billy Apple' timestamp='1390336769' post='2344273']
Exactly how do you bridge all the channels. Pic please?
[/quote]

It's the same way as guitards have been bridging the channels on their plexis for decades. Look at the mpa preamp pic. Plug into top left input, run a little effects hookup cable from the top right input to the input diagonally below it. Continue ad infinitum... Really can't wait for mine to arrive now! Like a bit of grind I does...

Link to comment
Share on other sites

[quote name='Billy Apple' timestamp='1390336769' post='2344273']
Exactly how do you bridge all the channels. Pic please?
[/quote][size=4][quote name='Bigwan' timestamp='1390337878' post='2344291'][/size]Look at the mpa preamp pic.[/quote]

Or my new avatar. Though to be fair that's only bridging three channels... for home use. ;)

Edited by discreet
Link to comment
Share on other sites

[quote name='discreet' timestamp='1390334576' post='2344229']
it has four Mullard ECC83s in it
[/quote]

Ah! That must be it. I gather this means one tube per channel, and that we're mixing four pre-amps, as in the "step up" model I mentioned.

I'd never heard of such a thing, but it seems ultra cool in my book.
Is it a feature of many amps?

Link to comment
Share on other sites

[quote name='BassTractor' timestamp='1390351418' post='2344517']
Ah! That must be it. I gather this means one tube per channel, and that we're mixing four pre-amps, as in the "step up" model I mentioned.
I'd never heard of such a thing, but it seems ultra cool in my book. Is it a feature of many amps?
[/quote]

No idea. This thing seems very quirky and is the only pre/power valve amp I've had experience of... there was an integrated SVT CL way back in the day and a 120W Orange before that, even further back in the mists of time... [size=3]mists of time...[/size] [size=2]mists of time...[/size]

Edited by discreet
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...