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Miten eroaa soundillisesti TEIDÄN kokemustenne perusteella JCM-800 2203, jossa inputit päällekkäin (vertical) sellaisesta JCM-800 2203:sta, jossa on inputit vierekkäin (horizontal)?. Näissähän on jo rakennusvuosilla eroa sikäli, että nämä päällekkäisinputlaitteet ovat niitä 80-luvun alkupuolen vekottimia ja vierekkäisinputlaitteet tehty 80-luvun puolivälistä 80-luvun loppuun tms.
 
Löysin asiasta tällaisen artikkelin:
 
"The JCM 800 series marked a very unique time in Marshall history. Marshall was free from a contractual distribution deal and in essence celebrated its “independence” with the introduction of the JCM 800 series. Cosmetically now changed with front and rear panels and chasis that extended all the way across the bottom of the amplifier heads, and its larger logo now put onto a fabric backing piece, this is the basic Marshall “look” that continues today.
 
Inside the circuit, the early master volume and non-master volume models continued and were essentially the same as the JMPs that preceded them. To my ears however, I hear just a slight bit more gain and brightness from the circa ’81-’83 JCM 800 master volumes. These were and are aggressive rock amplifiers and sound great. Unfortunately, with the “hype” surrounding the master volume models, especially the strength of the 100 watt 2203, its value has eclipsed the earlier JMP variations. Whether this will continue remains to be seen, but with Marshall recently “reissing” its 2203 model as well as bringing out the limited “Zakk Wylde” (Ozzy Osbourne) model also based on the 2203, the 2203 buzz is currently hot!
 
However, during circa 1985, the design of the 100 watt JCM 800 series changed in order to cut costs. The age of the “vertical input” style of inputs as used on 2203s and 2204s for years had ended. A new “horizontal input” configuration began and this in itself only meant that the potentiometers and input jacks were now mounted directly to the printed circuit boards rather than being wired up with flying lead wires. This obviously simplified construction and in itself was NOT such a big deal, but what WAS a big deal was the change in the filtering and power supply structure of the 2203 (but NOT the 2204 - which remained unchanged) that took place later in l986 – this was also designed to reduce costs. Unfortunately, this latter change altered the tone of the amp. When looking at a “vertical input” JCM 800 2203 (or earlier JMP 100 watt for that matter) at the chassis, a total of six filter capacitors (those large “cans” that look like tubes) were previously present. The first of the horizontal input models were basically unaffected and examples such as the one pictured below show a design with five filter caps rather than the previous six. The primary four caps grouped together that ran as two pairs in series, was still part of the design and corresponded to Marshall's early power supply design. The circa late-1986 2203's, to reduce costs further, incorporated reduced power supply requirements and specifications and was able to eliminate one "pair" of the series-run caps, reducing the number to three filter caps total. Unfortunately these new 2203's just didn’t have the same “punch” or power levels. Sure, they were still loud, but were much more grainy and thin-sounding as they were turned up. It did NOT help that at around the same time, the U.S.A. versions of the JCM 800 series began to re-adopt the EL34 tubes, which otherwise could've been a blessing. For Marshall’s best-selling 2203 and 2204 single-channel master volume heads, the switch in tubes actually limited the tone further since the 6550 – while not as quick to break up – still provided a fuller tonal range in this particular configuration. In essence, the "three-capped" 100 watt JCM 800 was the first Marshall that did NOT necessarily sound better as the volume went up - in fact, it began to sound worse - more grainy, thin, and muddy as the volume increased. REMEMBER: THIS is simply MY opinion represented above - you may prefer the later JCM 800's as is your right to do so!"
 
Itse kun en ole mikään tekniikkaguru niin viisaammat valaiskoot asiaa. Mikko Kankaanpää varmaankin tietäisi

Kun pääteputkien anodivirta kasvaa (eli soitetaan kovalla) AB-luokan putkivahvistimessa, virtalähde kyykkää (anodijännite laskee) - etenkin putkitasurilla varustetuissa koneissa. Tämä kuitenkin ilmenee myös puolijohdetasasuunnatuissa koneissa, varsinkin, mikäli virtalähteen suodatus ei ole riittävän suuri. Juuri tästä on nyt kyse.
 
Joku voisi siis pitää uudemman JCM-800:n soundia parempanakin! Riippuu varmaan runsaasti musatyylistä. Headroomihan tuossa vähenee.

Mä en jaksanut etsiä skemoja, ja varmistaa miten asia tässä tapauksessa on, mutta mun ymmärtääkseni konkkien määrän vähentyminen ei automaattisesti tarkoita, että kokonaiskapasitanssi muuttuisi.
 
Jotenkin tuntuu monissa tapauksissa, että kun vahvistimen kytkentää muutetaan oikeasti jopa parempaan suuntaan (kestävämmäksi esim., saundihan on makuasia), vintits-miehet ovat aina sitä mieltä, että vanhan saundi ja tatsi oli parempi. En tietenkään tiedä kuinka tässä on laita.
 
Mitenhän noi jcm-800 reissuet, kumpaa disainia ne on? Onko nekin huonoja?