| Author | Message | ||
     Rory Coupland (bigjilm) Username: bigjilm Registered: 06-2013 |
Is it possible a MMan site's schematic is wrong? Ive spent flamin ages & come to conclusion it just must be.. On 2275-130 schematic, C2 it says is 0.1uf (in my amp it is 1uf). C20 it says is 1 uf (mine is 0.1uf). [Its easy to find C2: its the furthest LHS (input area / preamp) and it is a BIG yellow 1uf.. not a small yellow 0.1uf! ] Can anyone verify my findings pls..? or I will go stark raving mad, take off all my clothes and attach probes to my soft dangly bits. rc | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Start hanging the probes! C1 in my 2475(same schematic) is correct. In fact, the way the board is designed, you would have trouble even getting the 1uF to FIT in the spot where the .1uF should go without the leads doubling back to the holes. That c1 should be the first cap all the way to the left or outside, depending on where you are looking at it from. Wait a minute-I thought you had a 2100-130. The SS driver version of the 2100-130 shows a 1uF cap there. | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
I see you have always said is was a 2275-130. Are you SURE you don't have a 2100-130? That would make it right. I just looked at your old photos. They do show a 1uF there. | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
The more I look at this, I just wonder if that was a test to try to get more bass. My 2-10 is bass lacking and I have never gotten around to doing anything with it. Maybe this is what they were after. | ||
| Rory Coupland (bigjilm) Username: bigjilm Registered: 06-2013 |
The probes are not yet attatched, but Im in my bithday suit ready.. Defo a 2275-130 (on back of amp) its a '115 HD one thirty' on front badge but I dont suppose that makes any differenece to chassis / layout. Im 100% sure C2 (Im talking about here, not C1) and C20 are as I mention, opposing the schematic. [Mine is -identical- to this ebay FS eg, a 2275-130 with the BIG yellow C2 (1uf) furthest LHS. Pic 5 best].. http://www.ebay.co.uk/itm/Vintage-Music- Man-HD130-Chassis-Guitar-Amplifier-Proje ct-/300916830881?_trksid=p2047675.l2557& ssPageName=STRK%3AMEWAX%3AIT&nma=true&si =fedOh3Ez%252FgiF%252FwYaq4ZD0q4IBEA%253 D&orig_cvip=true&rt=nc#ht_1670wt_966 rc | ||
| Rory Coupland (bigjilm) Username: bigjilm Registered: 06-2013 |
..and C20 is easy to spot too: its immediately to the RHS of the vertical orange wire in middle of board (again pic 5 of above link is best). [I may have confused C2 with C1 -either way- its the LHS cap Im on about there (C1 & C2 on schematic are both tiddler "0.1" ..mines a big yellomumma "1uf"]. | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
MAybe they decided that the 2100 sounded better so they tried it. It IS an export version, I think you said so maybe that's where they tried it. Interesting. | ||
| Rory Coupland (bigjilm) Username: bigjilm Registered: 06-2013 |
That sounds plausible Mike. But what about the C20 similar oddity? this one is in the reverb circuit, and goes to ground after R22 a 2.2k (whatever that sort of cap is called exactly) ie its not a coupling cap. Again schematic wrongly says this is a 1uf, and actually it is in mine a 0.1uf. My hunch/ 2p's worth: C2 and C20 have been mixed up by the schematic monkey.. and so the result in 1000's of amps the bass is a bit too phat (C2) and the reverb is a bit too weedy (C20) which I would say my amp sounds like (certainly the reverb sounds poor to me hence my trying to ascertain which cap -may- be worth a change in the reverb circuit and so trying to find the elusive C20 "1uf".. then my resultant head-scratching, gnashing of teeth, and general abject nakedness etc). | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
I personally would like the fat part. Don't use 'verb right now at all anyway. The amp I'm using out right doesn't even have it. Try changing the reverb cap and see what it sounds like. Fun to experiment! I'd leave the front end cap in there but I don't know mushy it's making YOUR amp. | ||
| Rory Coupland (bigjilm) Username: bigjilm Registered: 06-2013 |
Mike you and I should swap amps then! Im fine with a 2-10 (less bassy/ less volume for neighbours etc) and a 15" would give you your bit more 'size' / bass. I might tinker with that C20 reverb cap.. an itch youve made me scratch now! still at least I can leave off the probes to my gentlemen's area. |