Newbie Needs Help with Melody I2A3

morganc · « **on:** 20 Nov 2009, 04:59 pm »

So I just ventured into the tube world and bought a Melody I2A3 to pair with my Zu Essence speakers and I absolutely love the pairing, but........
I bought the unit from the dealer as he was clearing his stock and mine was the last he had and it was damaged en route to him. He gave me a great deal on it so i took him up on it and I was planning to use this as a trnaistional unit for the next 6 months. It worked great for one week and then one of the 2A3 tubes went out. He has offered me a guarantee until Jan 1st that if the unit does not work he will refund my money which I thought was quite fair. The damage was mostly to the paint job and really there is no obvious damage to any structure. The unit otherwise looks perfect. I guess I am just trying to figure out if I can determine if it is a bad unit or if it is just a bad tube that was damaged in shipment to me? Should I just order another tube and give it a try? If so, any thoughts on best place to buy a 2A3?
Additionally, I checked the bias and it is close to the recommendation everywhere except where the tube is blown. I assume that the bias will read zero for a dead tube, correct?
Thanks so much for the help!

FullRangeMan · « **Reply #1 on:** 20 Nov 2009, 08:39 pm »

If this tube amp was mine, I could want the custumer service/support take a look inside it right now, before you put a new tube.
I wish the OK from someone responsible from the Service.
Good Luck

ludimagis · « **Reply #2 on:** 22 Nov 2009, 04:55 pm »

I owned the I2A3 for awhile and paired it with Zu Druid, nice integrated & agree that it is an excellent match with Zu. The damage may have caused a problem with that socket leading to the power tube going. But power tubes do occasionally die early. Have to agree that you should contact the seller and at least have him send you a replacement tube so that you can see if it happens again. If need be, contact Jason @ New Quest Sound through agon or ebay. I've purchased current production tube from him; great guy and fair prices. A Sovtek 2A3 will be around $40. Good luck

morganc · « **Reply #3 on:** 22 Nov 2009, 07:21 pm »

Thanks. I took the advice of another tube supplier and rotated the tubes and the other tubes work fine in the socket of the tube that went out so I will assume that it is a tube issue. I have had a hard time finding a single tube. How important is it that the tubes are matched?Is this a big deal? Especially if they are all virtually new?
Thanks

FullRangeMan · « **Reply #4 on:** 22 Nov 2009, 10:15 pm »

Quote from: morganc on 22 Nov 2009, 07:21 pm

How important is it that the tubes are matched?Is this a big deal? Especially if they are all virtually new?

If the tube maker recommend matched tubes you must use matched pairs tubes, not doing it is a risk. They are paired electrically and the amp bias may need matched tubes for a right working.
Amps that may use unmatched tubes commonly have manual bias for every tube, the cousins of Melody, the PrimaLuna have automatic Bias for every output tube.

JoshK · « **Reply #5 on:** 22 Nov 2009, 10:55 pm »

This is a singled ended amp, I believe. If so, not matching isn't a big deal. Try to find a single, if you can, buy a pair and use your single as a back up in case it ever happens again.

If you rotated the tube and it worked then you are good to go.

lcrim · « **Reply #6 on:** 22 Nov 2009, 11:00 pm »

Its a push-pull amp and the tubes should be matched.

FullRangeMan · « **Reply #7 on:** 23 Nov 2009, 02:17 am »

The distributor site just inform it is ''Balanced design'' http://www.melodyhifi.com/I2A3.html
perphaps the two output tubes are SE bridged like the BAT, but I doudb.