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Parts for Denon 4400a monoblocks

Joined
May 2, 2020
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#1
Hi guys/girls

I have just received 2 Denon 4400a monoblocks secondhand. I purchased them both from 2 different sellers.
I thought it might be a good idea to take the cases off and look inside both of them and when I opened them up, to my surprise, they were slightly different inside.
One of them looks as though it has the original Denon circular transformer (part number: 2339577008) and the other has a square looking transformer (part number: 8B-DJW-624-01 TAM M 0124) and also smells a bit "smokey" inside.

I wanted to return them to original condition-perhalps the smokey smell is a result of the modification?

Where could I source a suitable transformer for this? When I google the original part number (2339577008), Im unable to find one.

Also, concidering that they are a bit old, is it worth changing the capacitors/resistors in them? or anything else for that matter?
Im a bit of a noob when it comes to such things but i have a "friend of a friend" who could carry out any any electrical work.

Many thanks,
Charles
 

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LTig

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#2
Hi guys/girls

I have just received 2 Denon 4400a monoblocks secondhand. I purchased them both from 2 different sellers.
I thought it might be a good idea to take the cases off and look inside both of them and when I opened them up, to my surprise, they were slightly different inside.
One of them looks as though it has the original Denon circular transformer (part number: 2339577008) and the other has a square looking transformer (part number: 8B-DJW-624-01 TAM M 0124) and also smells a bit "smokey" inside.

I wanted to return them to original condition-perhalps the smokey smell is a result of the modification?

Where could I source a suitable transformer for this? When I google the original part number (2339577008), Im unable to find one.

Also, concidering that they are a bit old, is it worth changing the capacitors/resistors in them? or anything else for that matter?
Im a bit of a noob when it comes to such things but i have a "friend of a friend" who could carry out any any electrical work.
Don't know about the parts, but I would check first if anything is required at all. Connect the speakers and listen:
  • A 50/60 Hz hum may hint to induction of line frequency into the audio circuits. If this happens on the one with the square transformer it may be worth to replace it by the original.
  • A 100/120 Hz hum may hint to dried elcaps, so it may be worth to replace them.
Edit: I had the POA6600 from ca. 1995 to 2004. I bought them used for a good price and sold them to a band for professional use (they insisted!). As far as I know they are still in perfect working order, therefore I don't think that you must replace any parts now.
 
OP
C
Joined
May 2, 2020
Messages
44
Likes
10
Thread Starter #3
Many thanks fo
Don't know about the parts, but I would check first if anything is required at all. Connect the speakers and listen:
  • A 50/60 Hz hum may hint to induction of line frequency into the audio circuits. If this happens on the one with the square transformer it may be worth to replace it by the original.
  • A 100/120 Hz hum may hint to dried elcaps, so it may be worth to replace them.
Edit: I had the POA6600 from ca. 1995 to 2004. I bought them used for a good price and sold them to a band for professional use (they insisted!). As far as I know they are still in perfect working order, therefore I don't think that you must replace any parts now.
Many thanks for your help-reassuring to know that your old amp has lasted this long with out spare parts! I was just concerned at the different transformers from the two mono amps and the burnt smell from the one with the replacement square transformer but, im yet to power on/test them as of yet as im waiting on delievry of speaker cables and a network streamer
 
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