ADA Depot - A Forum To Support Users of ADA Amplification Gear

Miscellaneous => Introduce Yourself => Topic started by: scsibear on May 07, 2016, 11:25:08 AM

Title: Greetings from Scotland
Post by: scsibear on May 07, 2016, 11:25:08 AM
Hey guys

Just joined the Depot a few days ago but had issues getting in, big Thanks to MJMP for sorting that out for me  :thumb-up:

Been playing about 36 years now and can't believe it's taken me so long to get an MP1, i've been running a JMP 1 for years into a 9100 50/50 Dual Monoblock with 5881's in it.
Anyway i got my Mp1 (unmodded) a few days ago now so looking forward to messing around with it.

cheers
scsi
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 07, 2016, 11:58:30 AM
Hey SB

Hi and welcome to the depot,sorry it took a bit longer then expected.
Title: Re: Greetings from Scotland
Post by: tomy on May 07, 2016, 02:14:29 PM
Welcome SB,

good to have new members aboard. I have a 9200 with 5881 in it too, great amp !

Cheers

TG
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 07, 2016, 05:58:58 PM
Hello SB,

    Welcome to the Forum :thumb-up:

    I would be curious to hear how you'd compare the two preamps through the Monoblock.

   Harley 8)
Title: Re: Greetings from Scotland
Post by: scsibear on May 09, 2016, 04:19:18 AM
Thanks for the welcome guys


@tomy: Yeah i like this amp a lot and i do favour the 5881's over the EL34's, just personal taste and all that, ya know.

@Harley: Sure man will do, it's been a bugger trying to get time to try the thing out  the other half's got me decorating the damn living room..that's rock 'n' roll i guess huh. when i get time i will tho  :lol:
Title: Re: Greetings from Scotland
Post by: rnolan on May 09, 2016, 04:44:34 AM
Hey welcome scsibear, I suspect you'll like the MP1 allot  :thumb-up: >:D .  You may want to put some new tubes in it though, depending what's in there and how hard they've worked.

Have fun with the decorating LoL  :wave:
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 09, 2016, 06:49:11 AM
@Harley: Sure man will do, it's been a bugger trying to get time to try the thing out  the other half's got me decorating the damn living room..that's rock 'n' roll i guess huh. when i get time i will tho  :lol:

I decorated my living room walls with my sword collection! I thought about adding a few guitars in between them, but Nahhh....they will be fine downstairs in my studio. Enjoy!

Harley 8)
Title: Re: Greetings from Scotland
Post by: scsibear on May 09, 2016, 10:21:40 AM
Thanks rnolan

I did love the guitar sounds of the 80/90's hair, when emm I actually had long hair too, these days it's more of the slap head variety, (..arrg the pain) but the sound and feel is still in my soul, i love the Ratt, White Lion sound, i even hear Mr Vai used an MP1 on his Passion and Warfare album, so it was a must buy.

Yeah i was thinking of re-tubing anyway at the moment it has Groove tubes GT2075's in both V1 and V2 but i have no idea how long they have been in there or what kind of use/abuse they have been exposed to. As regards the overall condition of the unit, it has typical rack rash as you would expect, however 2 knobs are missing one from the front and one from the rear, so i ordered some new ones from RS Components, it'll probably be getting put in to get a full service anyway, god knows how good the caps will be after this time OR perhaps  save a little and get a few mods done, the noise one mainly i'd like to keep the unit as it was no extra tube etc just new jacks and pots. Ohh and it's version one with the old switch on top for line level selection, so might have a few jobs for MJMP later down the line as he seems to be the man to go to for this kinda thing.

Regards
scsi
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 09, 2016, 11:14:39 AM
I think you mean GT7025's ;D
Title: Re: Greetings from Scotland
Post by: scsibear on May 09, 2016, 11:21:08 AM
LOL hahaha emm yeah that is exactly what i meant, maybe i have developed Dyslexia as well as hair loss :P
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 09, 2016, 11:22:29 AM
Yeah getting older really sucks  :lol:
Title: Re: Greetings from Scotland
Post by: rabidgerry on May 10, 2016, 02:27:52 AM
Hey scsibear

welcome from one fella celt to another!!  :thumb-up:

Good to have you on board.  Playing Edinburgh this year with my band as well!!  Love Edinburgh a lot!  Visiting just for a short holiday in June also!!!
Title: Re: Greetings from Scotland
Post by: rnolan on May 10, 2016, 06:22:22 AM
Hey scsibear, MJMP is a good person to help you out with a good service... or if you're up to a bit of soldering he can get you the bits you need (http://www.marshalljmpmodshop.net/miscellaneous_parts_and_replacement_tubes.htm).
Well the GT tubes are not original so they were changed out at some point.. Have a read through the tube section here for a bunch of good ideas for different tubes, very subjective area as they all sound so different so depends on the sound you like. One combination I can vouch for is a Mullard Short plate new sensor reissue in V1 and a Boogie SPAX7 (which is probably a JJ) in V2. My friend Mike went for this combination and it sounds great  >:D .
I think the noise mod replaces all the caps that need doing (and yes it's probably time  :facepalm: )
Also replace the memory battery (battery mod), if it's never been replaced, it is definitely time (a few here have had a battery fail recently, so you loose all your custom patches)
Rear jack mod replaces the front (and rear) input jacks.  The front jack takes the most wear so it up there on the things to do (but you cant get the jack sockets anymore, but fortuitously, the rear jack mod sorts this out  :thumb-up: ), the mod turns the rear jack into inst level input (stock is line input level) and replaces both the front and rear sockets.  The switch on top changes the main outs from line to inst level (to plug into a guitar amp input (inst level) or into a poweramp (line level)) so the rear jack mod doesn't affect this.
And of course there's the MDRT upgraded transformer  >:D :thumb-up:
Title: Re: Greetings from Scotland
Post by: scsibear on May 10, 2016, 08:58:12 AM
Hey RG nice to meet ya, yeah Edinburgh is nice when the sun comes out but this is Scotland so we know it more as Rain Central i think some of us even got webbed feet.

@rnolan: Ok i gave it a good run through today, i think the unit is pretty spanked, I did a full reset but it's very nasally, honkey even in some presets most of them actually, some have no preset whatsoever 31 - 64 is just silence as is many random others, 65 sounds like a flanger in the background but no sound from the guitar here either, (sounds like it's under attack by Klingons) i don't think even new tubes will fix that any ideas what's going on there ?

Also thanks for MJMP's link I'm gonna need it, BTW those mods you mentioned sound like they will be the ones i'll need, especially the rear ones as i'll be going in via a Furman PQ3 then into the mp1 then out to the RME Fireface 802. I'll have to discuss it with MJMP he'll know if the unit is beyond repair or not too, but i do hope it can be fixed.

Regards
scsi
Title: Re: Greetings from Scotland
Post by: Dante on May 10, 2016, 09:44:23 AM
Welcome to the Depot, SCSI Bear!!

Good to have you along. I'm sure MJMP will take care of you & get the preamp in working order.
Title: Re: Greetings from Scotland
Post by: scsibear on May 10, 2016, 10:14:05 AM
Hi Dante

Thanks for the welcome, and the correct pronunciation  :))

Yeah i hope he can suss out what's going on with the unit
Title: Re: Greetings from Scotland
Post by: Dante on May 10, 2016, 10:57:26 AM
Hi Dante

Thanks for the welcome, and the correct pronunciation  :))

Yeah i hope he can suss out what's going on with the unit

I almost wrote it phonetically = Scuzzy Bear  :thumb-up:
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 10, 2016, 02:02:25 PM
Hey SB

What software version does it have,you see this at startup,it will display either 1.36,1.37 or 1.38
Normally these V1 eproms have 29 presets so strange you have 31 after the reset?

What input do you use,the front or the back one?
Title: Re: Greetings from Scotland
Post by: scsibear on May 10, 2016, 05:21:12 PM
Hi Marshall, yeah it's V1.38 on start up, and i've only tried the front face input so far, as regards the presets, this was me trying each one going from 1 to 128.
Some are totally blank (no sound at all) at least one makes a real bad Flanging noise and some just have the exact same tones, however i had a listen to one of the guys mp1 sounds from the forum, it was on the MDRT upgrade thread before he did the upgrade and my unit sounds nothing like that  i wish it did, this is just really nasally and honkey  I suspect that's prolly the tubes needing renewed.
However i think i'll deffi have to send it over to you for a service and an upgrade.

Regards
scsi
Title: Re: Greetings from Scotland
Post by: rabidgerry on May 11, 2016, 12:12:15 AM
Hey scsibear this wasn't my MDRT thread was it and the clips I posted?

Ok change of plans, not playing Edinburgh now, it has been changed to Glasgow!  Played there before so it would have been nice to play Edinburgh just for somewhere new.
Title: Re: Greetings from Scotland
Post by: rnolan on May 11, 2016, 03:42:26 AM
Hey scsi, well definitely could do with new tubes and unless the rear jack has been modded (I suspect it hasn't) the rear input is line level, so not a place to plug in the guitar directly.
Sending it to MJMP for a revival/service is a good idea.  I have some ideas re the sound, just guessing and thinking out loud...  I think the front input jack may be worn (as I said before, it takes the majority of the wear and tear over the years).  So rear jack mod will fix that (and at this age it should be replaced anyway). My reasoning is there may not be enough signal hence thin nasal tones. So you reloaded the factory settings ? (1 to 29), the others (30 to 128) are all user slots and who knows what the previous owner(s) put there  :dunno: if anything (hence blank patches).  But you can also overwrite 1 to 29 with whatever you want, I'm assuming right now they are the factory defaults since you did a factory reset which takes the 29 patches from the EPROM and overwrites the user 1 to 29 slots.
So lets try to get patch 1 (Marshall patch) going/tested.  This patch should sound good and full, so try it and let me know how it goes.
So a nasal sound (while it could be lots of things) could be eq settings (but the eq on the factory presets are fine so patch 1 should be good from that perspective).  The flanging you get on the other patch could be chorus settings ?, also there are trim pots for the OD1 and OD2 tube circuits, if they've been changed it could cause gain issues.
Ok just re-read your post and looked up the furman parametric and the Fireface (which is a digital I/O interface for PC recording). So (pls correct me if I'm wrong) you are monitoring through a studio style setup ie going direct from MP1 to I/O to PC ? and then listening through full range speakers so no wonder it sounds nasally  :facepalm: there's way too much top end because the speakers are full range.
The MP1 is designed as a stage preamp to plug into a clean/transparent stereo poweramp driving 2 (or a stereo) guitar cab(s) loaded with 12" guitar speakers (eg 2 x Marshall quad boxes).  All the MP1 patches have the right balance of treble to sound good through a 12" cone (not into the tweeters in full range monitors) so you end up with wayyy too much treble going direct.  To go direct with MP1 most use a cabinet simulator which, apart from other things, basically cuts back the excess treble (eg ADA GCS3, Micro cab etc) to sound the same (similar) to what the cabs sound like.
Now interestingly, the headphone out on the MP1 has a very simple "cab sim" style filter to remove the excess treble so it sounds ok in the headphones (which are also full range). It's not as elaborate and versatile as a separate cab sim but if you run a R/T/S to 2 x T/S lead (stereo jack to 2 x mono jacks (same as an insert lead)) from the stereo headphone out jack to 2 channels on your Fireface (pan one hard left the other hard right) it should sound much better (not as good as power amp and cabs  >:D or as good as decent cab sims) but usable for now.
If you are going to use the PQ3 (personally I don't think you'll need it) I wouldn't put it in front of the MP1, hey you can but not good gain structure, let the MP1 input just get straight guitar.  You could use the PQ3 in the FX loop, as PQ3 is mono it's not so good after the MP1 (MP1 should be run stereo if you can).  The PQ3 is also a preamp so you could run it into the rear line level input, it will have too much gain to run into the front input.
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 11, 2016, 04:19:08 AM
Well I think R already answered your questions  :lol:

The 1.38 has only 29 presets.
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 11, 2016, 05:48:00 AM
Hey scsibear,

   Actually, a slight correction to Richard's post about direct recording with the headphone output. If I'm not mistaken, in one of the MP-1 manuals, they tell you that you can use the headphone jack to go direct, but they recommend running through an outboard EQ first, and they also give the frequencies to boost or cut to get the cab sim effect. I'll have to go look for it to be able to post the settings.

    Harley 8)
Title: Re: Greetings from Scotland
Post by: rabidgerry on May 11, 2016, 08:52:56 AM
hmmm strange I record all my preamps using the main outputs direct into my multi-track.  Never had an issue.

Are you guys telling me I should be using the headphone out?  Why?
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 11, 2016, 03:35:46 PM
Hey RG,

   If it works for you that way and it sounds good, then it's the right way. There are a lot of ways to do recordings, just like there are a lot of ways to place microphones. All I was referring to was one of the ways ADA offered to get a cab sim recording with the original MP-1 since that was the only model that didn't have a built-in recording output.
   In the end, if the sounds you are getting, are pleasing to your ears, then go for it! The technique doesn't matter as much as the results.
  Harley 8)
Title: Re: Greetings from Scotland
Post by: rabidgerry on May 12, 2016, 01:18:56 AM
Hey RG,

   If it works for you that way and it sounds good, then it's the right way. There are a lot of ways to do recordings, just like there are a lot of ways to place microphones. All I was referring to was one of the ways ADA offered to get a cab sim recording with the original MP-1 since that was the only model that didn't have a built-in recording output.
   In the end, if the sounds you are getting, are pleasing to your ears, then go for it! The technique doesn't matter as much as the results.
  Harley 8)

I hear ya Harley!  :)

I just thought that perhaps I overlooked a dedicated recording output using the device.  I would never have thought to use the headphone out unless I was desperate or something, since I wasn't using an amp in my DI setup I always just used the main outs.  Interesting and good to know though that there is the extra option.
Title: Re: Greetings from Scotland
Post by: rnolan on May 12, 2016, 01:38:30 AM
Hey Harley, I don't recall reading that, I'll give the manual a read (it's been a while).  EL posted a while ago re using the headphone outs as alternate to the main outs.  MJMP told him/us about the filter (caps IIRC) in the headphone circuit which you'd need to take out if you wanted the signal the same as the main outs.  It's pretty basic filtering just to take the top end off a bit (like a basic low pass filter) so the headphones sound ok.  You could achieve a similar effect using eq on your desk/DAW etc.

Hey RG, do you need to eq much when you go direct from main outs ?
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 12, 2016, 05:32:12 AM
Hi Richard,

   I'm not 100% certain it is in the manual...I think that was where I saw it. Possibly the V.2.01 manual. I would have to look for it, but that could take a while, since it's been years since I saw that. I remember it was a footnote about the MP-1.

  Harley 8)

  Just an after thought; it may actually have been in an issue of ADA Trendz
Title: Re: Greetings from Scotland
Post by: scsibear on May 12, 2016, 06:02:15 AM
OK let me try to address some of these comments

@RG: yes it was your MDRT Thread with the pix :thumb-up: and even better your not playing Edinburgh, as I'm in Glasgow anyway LOL so i can maybe pop along and see you guys  ;) Just let me know where and when man.

@rnolan: Yep I have been going in from the guitar via the front(TR)  not the rear line in(TRS), I totally agree as regards what and if the previous owner has put patches all over the place including blank ones, lemmie try out 1st patch for ya (Marshall) I'll use a passive and an active...ok Active sounds fine (Warlock with SD Heavy Metal Live Wire2) quite ballsy but could do with some EQ fixing, with the passive (Gibson MIII Deluxe Stock pups) hardly any distortion at all sounds more like the volume has been rolled off..(this is making me think valves here !!)
What your saying about the internal trim pots is also possible who knows if he's been prodding & poking.

When i was listening the 1st time and it was really nasally it was through 400 Ohm headphones in the headphone socket at the back  I see it requires 600 Ohms cans that might explain that one, You are correct as regards FF802 digi interface and it's like a studio setup as you say..However I have not decided as yet if I would be recording direct from the MP1 into the FF802 or just mic up the cab (Pre>50/50 dual monoblock into 4 x 12) I haven't even tried to record it direct or play it through the FF802 yet. I've only tested it via the cans socket and through the main amp & cab. Also I was toying with the idea of getting the two tone live for cab sims via the MP1's fx loop. I see what your saying about the insert Y lead idea and also with the PQ3 about too much gain the PQ3 has  low in and out sockets as well as a high in and outs  this is what the likes of vita Bratta did Low into PQ3 Low out to MP1, lots of options to consider here for sure thanks for the tips on that.

BTW I am ok with a soldering Iron LOL I was looking through as i had mentioned before RG's thread about the new tranny and just kept going with the other mods it actually looks like fun, i'd be quite into that, but wouldn't be sure which mod to start with, given that it may need quite a few it may work out better just posting it to Belgium and getting the lot done in one fell swoop
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 12, 2016, 03:42:40 PM
Hey scsibear,

    OK, I was combing through the ADA Trendz magazines and finally came across what I was looking for.
    Go to the ADA Trendz section from the Home menu, and look for Vol2-no1, and download the PDF file. When you open it, go to page 9, and the article is there under the heading: Attack of the Killer Tone.

    They give a starting reference for using the outboard EQ from the headphone jack to record direct. I never tried it, but hope it works out for you.

     Harley 8)
Title: Re: Greetings from Scotland
Post by: scsibear on May 13, 2016, 05:41:33 AM
OK HH I'll go and DL it now and have a look, Thanks

Regards
scsi
Title: Re: Greetings from Scotland
Post by: rnolan on May 13, 2016, 08:44:47 AM
Hey scsibear, that's not good about the stock Gibsons, they should have plenty to drive that patch. I agree tubes ??? but I'm thinking input jack also ?? If your up for the journey it is fun to do it yourself, on the other hand sending it to MJMP for a makeover is a good idea  :dunno: .  Now f you do the battery mod, all the patches will be wiped (probably a good idea, clear the deck as it were), then reload the factory presets (they come off the EPROM) and it's just like new, 29 patches and the rest blank (fill to your hearts content).
Initially, I'd get it going as intended, so Guit > MP1 > 50/50 > 2 x cabs (or wire your cab stereo, it makes a huge difference to run in stereo, I'll never go back to mono...). Once you get the basics sorted, combine some FX (delay, reverb (is all I use)) heaven on a stick... Now new tubes are always a good idea (have you read through the tube choice threads here ? lots of good ideas and opinions).  However, I can personally vouch for a Mullard short plate (new sensor reissue) in V1 and a decent JJ (or Boogie SPAX7 which is a JJ) in V2 as this is what Mikes using and it sounds great (Gibson LP Classic). Personally I like the Mullard long plates (new sensor reissues), they would also work very well.

Here's something to try, Guit > (inst lv in) furman eq (Line lv out) (but eq flat (to start))> MP1 rear (line lv in) > 50/50 > stereo cabs Just to isolate the front jack, I think its had its day based on your active/passive test
Title: Re: Greetings from Scotland
Post by: scsibear on May 14, 2016, 02:12:43 PM
@Richard

Yes i have read the Tubes thread and it's a very interesting one with many options, so kind of at a loss as to which pairings might be best, I see you recommended the Mullard short plate and the SPAX7 (Mikes set up) tho you say you prefer the Mullard Long plate (what's the difference between the short & long and can you say why you prefer the long ?).

I've actually just ordered a new helping hands, with magnifier & light and had recently just upgraded my soldering gear.
I would like to try do some of the mods myself (i suppose if i make a mess of it i can always still send it over to MJMP's anyway) telling him what i exploded.

Well new valves first of course, then what ? Battery, Noise, MDRT, Jack sockets ???
In what order would you recommend doing the mods ?? is there a preferred order at all ?

Ohh and as for Stereo cabs, my 4 x 12 is actually an old original Line 6 412s Stereo cab with the eminence speakers 75 each so a 300 watt cab
only thing is I have NEVER used it in Stereo I always just used it mono to be honest I'm not too sure how to set it up as Stereo
perhaps you can elaborate !
On the back it has 2 inputs and switchable options  these are:

LEFT/Mono : 16 ohm per side Stereo OR 8 ohm Mono(left only)
RIGHT : 4 ohm per side Stereo OR 2 ohm Mono (left only)
The 50/50 has a switch for each amp 8 or 16 ohm out for amp A and the same for Amp B
Would i just switch the cab to 16ohm and plug the left side into amp A and the right side into Amp B and set both Amp switches to 16 ohm ??
would that work then in stereo ?

Regards
scsi (Ray)

Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 14, 2016, 03:00:08 PM
Hi scsibear.

   I can't help with the cab plug ins, because I'm not familiar with Line 6 gear at all.
   As for the valves, I can tell you that the short plates will have a more crisp sound in general. They are more for high end definition IMHO, whereas long plates give more bottom end emphasis. This helps smooth things out a bit, and balance the overall output of the preamp tone.
   My personal preference for the MP-1 would be valves that have the long plates, since I seem to hear enough high end crispness, and would like to get more emphasis on the low mids and bass frequencies. Then again, I primarily play Stratocasters.
  Also, keep in mind Richard plays MP-2's, and those are completely different from the original MP-1. I like the sounds of the Mullard long plate RI my MP-2's as well.
   In the end, whatever combination or pair of valves gives your MP-1 the sounds that please your ears, is the right one.

   Harley 8)
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 14, 2016, 03:58:58 PM
Do you have some more info about that line6 cab?(manual or model nr)
Title: Re: Greetings from Scotland
Post by: scsibear on May 15, 2016, 08:39:23 AM
@HH: Yeah I kind of figured it was just down to what sounds right to my ear as you said.  The 4 x 12 has very good low end, real strong, warm, and good all round projection which i like.
I originally started on the bass and when i moved over to the guitar i was running it through a bass amp at the time, and as i got more guitar oriented gear i still liked having a good strong low end growl and still do to this day, I guess it's just what i got used to.
I think it's just a case of pick two types and see how they sound, probably an ongoing process til I find what i like best.

@MJMP: I'm sorry I cannot find the data sheet for the 412s anywhere, and the serial# has been well buffed off from years of gigging (van rash) i bought it new 16 years ago. They made 3 of them over the years, the one i have is the original one (Red/Silver grill cloth) built for the Flextone 1 and Flextone 2 amps and had Eminence Tube Tone speakers in them, the second one was built for their new Vetta Amps which took over from the Flextone 1 and 2 series these had Chinese Celestion V30s in them (Black grill cloth) very fizzy and no bottom end apparently , the last ones were built for their Spider series amps (Black grill cloth), I'm not even sure what's inside those but i've heard they are supposed to be pretty crappy from what I've read, but having never heard one i honestly couldn't say apparently they were based on a bogner 4 x 12 (looks wise).

Regards
scsi


Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 15, 2016, 09:46:55 AM
Ok I see now,so switch to the right  16 ohm/side if you plug it in stereo or 8 ohm if you plug it into the left side only
Switch left 4 ohm stereo or 2 ohm mono.
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 15, 2016, 12:12:56 PM
I see the switch there too. Am I the only one who thinks their mathematics is off?
160 watts per speaker? Doubtful, more like 80 watts @ 8 Ohms each is my guess. That must be 160 watts per channel if you run the cab in stereo. See what happens when you let people drink beer on the job?

From what I'm seeing here, it looks like you can run  in stereo by plugging in 2 speaker cables, which will run 2 speakers wired in series per side. You can select between 4 and 16 Ohm in stereo mode. The switch cuts the impedance in half.
Plugging into the left side runs the cab in series/parallel in mono mode. You have to be careful not to run that in 2 Ohms in mono, or it's goodbye poweramp.

That would work in stereo with almost any ADA poweramp. and most of any other you might try, albeit Marshall, Boogie, etc. You just have to mind the poweramp impedance requirements.

Harley 8)
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 15, 2016, 02:16:25 PM
Yes most solid state amps don't really like 2 ohms,usually doesn't hurt a tube amp.
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 15, 2016, 06:26:07 PM
@MJMP,  I cooked the output transformer of a 1973 Super Lead 100, (Marshall), because of mismatched impedance once. That was a costly repair, and the amp never did sound the same after that. I always make sure I'm using the correct impedance after that experience, and I never plug into an unknown cab, that I can't be certain of the impedance.
    I guess you could say I'm a bit paranoid about messing up another great sounding amp that way.

   Harley 8)
Title: Re: Greetings from Scotland
Post by: scsibear on May 16, 2016, 06:43:13 AM
Well the good thing is that the 50/50 has only 2 options and this is either 8 ohms or 16 ohms, personally I'd prolly set the amp for 16 ohms out A and B and into left and right switching the cab to the 16 ohms option.

Does that sound about right ?
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 16, 2016, 01:07:32 PM
That would be the way I would do it. :thumb-up:

Harley 8)
Title: Re: Greetings from Scotland
Post by: El Chiguete on May 16, 2016, 09:27:32 PM
Hey scsibear,

    OK, I was combing through the ADA Trendz magazines and finally came across what I was looking for.
    Go to the ADA Trendz section from the Home menu, and look for Vol2-no1, and download the PDF file. When you open it, go to page 9, and the article is there under the heading: Attack of the Killer Tone.

    They give a starting reference for using the outboard EQ from the headphone jack to record direct. I never tried it, but hope it works out for you.

     Harley 8)

Has anyone tried this out allready??? I have no time to try it out these days.
Title: Re: Greetings from Scotland
Post by: rabidgerry on May 17, 2016, 03:36:12 AM
Quote

@RG: yes it was your MDRT Thread with the pix :thumb-up: and even better your not playing Edinburgh, as I'm in Glasgow anyway LOL so i can maybe pop along and see you guys  ;) Just let me know where and when man.

Ahh I thought so.  Those clips are recorded with the original tranny.  I have yet to post any new clips with the MDRT and noise mod completed.  I will do soon though.  Not sure how much of an A/B will be able to be made now.  Some of the differences are in the feel and other things as well.  I'll give it a go.

Oh when I find out where we are playing in Glasgow I'll give you a shout man.  Don't know the venue yet.
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 17, 2016, 07:25:47 AM
@Harley,i was actually pointing out that a tube amp can withstand more abuse,like you can even short the output and it will not blow up in an instand like a SS amp would do.But you are right you always need to use the correct impedance setting on a tube amp.
Title: Re: Greetings from Scotland
Post by: Harley Hexxe on May 17, 2016, 07:05:39 PM
@MJMP

    I agree, butr when I think of tube, (valve) amps, I tend to think of the older point-to-point amps. When it comes to anything on a printed circuit board, I can't help feeling that they are not as durable, or tolerant to parameter changes like this. That is why I try to err on the side of caution.

   Harley 8)
Title: Re: Greetings from Scotland
Post by: MarshallJMP on May 18, 2016, 04:02:29 AM
Well the older amps ,quality wise were a lot better then the amps they make these days.
Title: Re: Greetings from Scotland
Post by: rnolan on May 19, 2016, 06:53:02 AM
@Richard

Yes i have read the Tubes thread and it's a very interesting one with many options, so kind of at a loss as to which pairings might be best, I see you recommended the Mullard short plate and the SPAX7 (Mikes set up) tho you say you prefer the Mullard Long plate (what's the difference between the short & long and can you say why you prefer the long ?).

I've actually just ordered a new helping hands, with magnifier & light and had recently just upgraded my soldering gear.
I would like to try do some of the mods myself (i suppose if i make a mess of it i can always still send it over to MJMP's anyway) telling him what i exploded.

Well new valves first of course, then what ? Battery, Noise, MDRT, Jack sockets ???
In what order would you recommend doing the mods ?? is there a preferred order at all ?

Ohh and as for Stereo cabs, my 4 x 12 is actually an old original Line 6 412s Stereo cab with the eminence speakers 75 each so a 300 watt cab
only thing is I have NEVER used it in Stereo I always just used it mono to be honest I'm not too sure how to set it up as Stereo
perhaps you can elaborate !
On the back it has 2 inputs and switchable options  these are:

LEFT/Mono : 16 ohm per side Stereo OR 8 ohm Mono(left only)
RIGHT : 4 ohm per side Stereo OR 2 ohm Mono (left only)
The 50/50 has a switch for each amp 8 or 16 ohm out for amp A and the same for Amp B
Would i just switch the cab to 16ohm and plug the left side into amp A and the right side into Amp B and set both Amp switches to 16 ohm ??
would that work then in stereo ?

Regards
scsi (Ray)
Hey Ray, I've been away from here a little bit lately, so I'm going to respond to this post from here (there are other posts to this I haven't read yet but I just wanted to answer this directly  :wave: . Ok so your cab  is capable of stereo or mono (it's just how the wiring goes and what the speaker(s) (nominal!!) impedance's are (from what I can tell they are all 8 ohm speakers))). So in stereo you would use both inputs (R & L (and switch to suite?)), and go for the 16 ohm option on the speaker inputs and the power amp outputs.
Now I can explain why if you are interested ? Fundamentally, you want to match your power amp > speaker (nominal) impedance (so you don't blow shit up...).
Title: Re: Greetings from Scotland
Post by: rnolan on May 19, 2016, 07:19:21 AM
Hey Ray, I've just "scanned over" the other posts/replies, the only way the the numbers stack up for your cab is that they are all 75w 8 ohm speakers (x 4) in your cab.  so in stereo you can have 2 x 4 ohm or 2 x 16 ohm (2 x 16 ohm is my recommendation given your amp likes 8 or 16 ohm loads). Hey if you had a ADA B200s I'd go for the 4 ohm load...
Understand that:
in parallel 8 + 8 = 4; 16 + 16 = 8, 4 + 4 = 4 etc (halves)
in series 8 + 8 =16, 4 + 4 = 8 etc (doubles)
So many boxes are wired in a combination of series and parallel to give the power amp the best nominal impedance. Your box gives you choices..., Mono 300w (2 ohm or 8 ohm). or stereo 150 w per channel (4 ohms or 16 ohms) because the speakers are 75 w 8 ohm.
Title: Re: Greetings from Scotland
Post by: scsibear on May 20, 2016, 05:19:44 PM
Hey Richard,
Yes you are exactly correct they are all 8 ohm speakers (4 of em) at 75 watt each so i am gonna go down the road of inputs L & r on the cab set to 16 ohms and both out of the amp A & B set to 16 ohm as well, that should work with no flames or big nazzy pop noises :)

Regards
Ray
Title: Re: Greetings from Scotland
Post by: rnolan on May 21, 2016, 02:03:12 AM
 :thumb-up: way to go.