Jeg har sett en del forsterkere med KT120 (Russisk Tung Sol) som har havarert.
I det siste har jeg hatt litt utveksling med Audio Research.
Her er advarsel som gjelder et par AR forsterkere.
Hi Hans:
KT120s are a no no in the VT100: The horizontal mounting causes the poorly-supported KT120 plate structure to sag inside the tube which can lead to early failure. Also, the extra weight of the KT120s causes them to sag and lose contact with the sockets –which as you know --can cause catastrophic failures! Further, the higher heater current requirement of the KT120 will make the power transformer run hotter and may possibly shorten its service life. Stick with 6550s.
The REF210 requires a now-discontinued factory mod to enable the use of KT120s. KT120s will NOT WORK without the mod and will damage the REF210! Since the mod. was discontinued, we recommend the owner stick to 6550s. And, before the customer asks –NO, we will not install the mod. It has been retired.
Best regards,
Chris Ossanna
Hi Hans:
FYI, we do try to offer updates for a few years. But after demand falls off for a particular update, we no longer stock the parts required. You would laugh if I told you how many people I have to turn away wanting updates we discontinued over 20 years ago J These folks must think we have a parts stock room the size of the US government warehouse where the Ark of the Covenant disappeared into at the end of “Raiders of the Lost Ark”…
Chris
Jeg vil si at det er svært risikabelt å benytte KT120 i forsterkere som ikke er konstruert for disse.
Selv om forsterkerprodusenten sier at de kan benyttes som alternativ til de originale vil jeg si som Chris Ossanna hos Audio Research:
"Stick with 6550's"
Mange mener at KT120 gir mer power eller høyere effekt enn f.eks. 6550.
Det er feil. Strømforsyningen bestemmer hvor mye forsterkeren kan yte.
Hvis det er noen forskjell er den i alle fall marginal og langt fra hørbar.
I det siste har jeg hatt litt utveksling med Audio Research.
Her er advarsel som gjelder et par AR forsterkere.
Hi Hans:
KT120s are a no no in the VT100: The horizontal mounting causes the poorly-supported KT120 plate structure to sag inside the tube which can lead to early failure. Also, the extra weight of the KT120s causes them to sag and lose contact with the sockets –which as you know --can cause catastrophic failures! Further, the higher heater current requirement of the KT120 will make the power transformer run hotter and may possibly shorten its service life. Stick with 6550s.
The REF210 requires a now-discontinued factory mod to enable the use of KT120s. KT120s will NOT WORK without the mod and will damage the REF210! Since the mod. was discontinued, we recommend the owner stick to 6550s. And, before the customer asks –NO, we will not install the mod. It has been retired.
Best regards,
Chris Ossanna
Hi Hans:
FYI, we do try to offer updates for a few years. But after demand falls off for a particular update, we no longer stock the parts required. You would laugh if I told you how many people I have to turn away wanting updates we discontinued over 20 years ago J These folks must think we have a parts stock room the size of the US government warehouse where the Ark of the Covenant disappeared into at the end of “Raiders of the Lost Ark”…
Chris
Jeg vil si at det er svært risikabelt å benytte KT120 i forsterkere som ikke er konstruert for disse.
Selv om forsterkerprodusenten sier at de kan benyttes som alternativ til de originale vil jeg si som Chris Ossanna hos Audio Research:
"Stick with 6550's"
Mange mener at KT120 gir mer power eller høyere effekt enn f.eks. 6550.
Det er feil. Strømforsyningen bestemmer hvor mye forsterkeren kan yte.
Hvis det er noen forskjell er den i alle fall marginal og langt fra hørbar.
