Martin Audio – MA2.8s Amplifier
ENGLISH
9
5.4.1 T he M LS ¸¸
¸¸
te ch no log y :
MLS swi tch es on rea r p an e l
5.4.2 T he p ro b le m:
If yo u a ssum e tha t a p ow e r
a mp lifie r ca n d elive r 10 0 0
w atts in to 8 oh ms, a nd is
d esig ne d to b e ab le to ru n in to
2 o hm s. Th eo retically, it
sho uld b e ab le to d e live r 4 00 0
w atts in to th e 2-oh m loa d .
V ery fe w p ro fession a l po w er
a mp lifie rs a re ab le to d o this,
a s all con ve n tion al po we r
a mp lifie r de sig ns a re a
com prom ise b e tw ee n p ow er
d issipa tio n, co sts, size etc.
M ost am p lifie rs can de liver o nly 7 0% or less o f the ir th eo re tical
p ow er in to 2 oh ms. T his is du e to re sistive lo sse s in th e po w er
sup ply a nd th e use o f cu rre nt limitin g to p rotect the o u tp ut
sem icon d ucto r d evice s.
5.4.3 T he s olu tion :
T he solu tion is to u se a “C on sta nt P o we r Co n ve rte r”. Th e
con ve rte r is co nn ected b e tw ee n the p o we r su p ply a nd the line a r
p ow er a m plifier. Th e m ain fea tu re of th e Co n stan t P ow er Co nve rter is tha t it ca n p ro d uce mo re cu rre nt th an it takes
fro m th e p ow e r su pp ly, a n d th is wa y o ve rcom e s th e losse s in the p ow e r su p ply wh e n driving lo w im p ed an ce s. As
p ow er is the prod uct o f curre nt an d volta ge , a n incre ase in curre nt re qu ire s a red uctio n in vo lta ge . Th is re d uction in
volta ge also ca uses th e d issipa tio n in th e o utpu t d evice s to be low e r. T h e cu rre nt limit pro te ction thre sh old can b e
a djuste d for a mu ch high e r cu rre nt, so it ca nn ot in te rfe re w ith the re qu ire me nt by th e lo ud spe ake r im pe d an ce cu rve.
6 I NS TA LL A TI O N
6 .1 M o u n t in g
T he a mp lifie r is tw o rack u nits high (2 U) a n d we igh s 10 K g (2 2 lb s) a n d will mo un t in a sta nd a rd E IA 19 ” rack. Am plifiers
m ay b e sta cke d dire ctly o n to p o f ea ch othe r. Th e re is n o ne e d fo r spa cin g be tw e en u n its. If it is th e inten tio n to fill a
rack with am p lifiers, we re co mm e nd ra ckin g is started from the bo tto m of th e ra ck. It is also re co m me nd e d th at re ar
sup po rts a re used fo r am p lifiers m ou n te d in th e m id dle o f th e rack, espe cia lly if use d as p a rt o f a p ortab le system .
6 .2 C o o li n g
Y ou r am p lifie r uses a fo rce d air coo lin g syste m to ma in tain a low a n d eve n op era ting te mp era tu re . A ll fa n co o le d
M AR TIN A UD IO MA series a m plifie rs ha ve fron t to rea r co o ling . N ever try to re ve rse th e dire ction of a irflo w, as the
a mp lifie r ne e ds a p ressu re ch am b er b e tw ee n the fa ns a nd th e interna l h ea t sin k a nd th is o nly o pe rates in o ne
d irectio n of th e airflow .
M ake su re th e re is a de qu a te a ir su pp ly in fron t o f th e a mp lifie r, a n d th a t th e rea r o f th e a mp lifie r ha s sufficie nt sp ace to
a llow th e exh au st a ir to esca
e . If the a m
lifie r is ra ck mo u nted
d o no t u se co ve rs or d oo r o n the fro n t or re ar o f the
Type of mode Pow er /Impe da nce
C h.A C h.B
C on ve ntion al mo de 1 10 0/8 1 10 0/8
1 50 0/4 1 50 0/4
1 70 0/2 1 70 0/2
H ig h vo lta ge mo de 9 4Vrms 9 4Vrms
1 10 0/8 1 10 0/8
6 50 /1 66 50 /1 6
L oa d ma tch in g 1 30 0/8 1 60 0/4
2 30 0/4 2 40 0/2
8 20 /8 8 30 /4
Pow er s h ar in g 3 20 0/2 1 66 0/2
3 20 0/2 2 30 0/4
3 20 0/2 1 30 0/8
L imited po we r 1 66 0/2 5 20 /8
2 00 0/2 8 20 /8
1 00 0/4 1 00 0/4
Bi- amp mod e3 20 0/2 2 30 0/4
2 30 0/4 1 30 0/8
1 30 0/8 6 50 /1 6
2 30 0/4 8 30 /4
Tab le 2
All material © 2007. Martin Audio Ltd. Subject to change without notice.
(33 páginas)
(10 páginas)
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Comentários a estes Manuais