Struck Gold; gotTannoy 15" Monitor Reds

[SIDEWINDER18X]

Hi Rajesh,
Are these alnico drivers ?. If yes ! They will need re-magnetizing for sure.

 

[captrajesh]

Yrs they are. But why they appear to be working perfectly fine

 

[SIDEWINDER18X]

Yrs they are. But why they appear to be working perfectly fine

They will work fine but will produce less output in the upper mid band region due to flux loss.
If you search the web you will come across the fact that all vintage alnico drivers needs re-magnetizing.

 

[adityapm]

They will work fine but will produce less output in the upper mid band region due to flux loss.
If you search the web you will come across the fact that all vintage alnico drivers needs re-magnetizing.

What you say is a possibility only when the drivers were continuously hard-driven (meaning heavily played), which normally would result in transferring more heat to the alnicos, and here they have a tendency to lose some of the flux density. Otherwise normal playing will not do any damage.

Ferrites however do not suffer from this issue, though their modulation linearity is somewhat less than that of the alnicos, and as a result for the same target linearity one will need a much heavier (more powerful) magnet compared to the other.

 

[SIDEWINDER18X]

What understandingy is a possibility only when the drivers were continuously hard-driven (meaning. heavily played), which normally would result in transferring more heat to the alnicos, and here they have a tendency to lose some of the flux density. Otherwise normal playing will not do any damage.

Ferrites however do not suffer from this issue, though their modulation linearity is somewhat less than that of the alnicos, and as a result for the same target linearity one will need a much heavier (more powerful) magnet compared to the other.

I have reconed several vintage alnico drivers. I always take a note of the gap strenght for record or reference. In atleast 90% cases had found reduced flux value in them. I do remagnetize them before recone. You can never predict or guess that every thing is alright until you measure it and see for yourself.
And as to modulation linearity ..... this is something off topic & are advanced tech talk.
They might not be simple to understand by most of the members in this forum. I am sorry to say this, but this is hard truth. Lets make discussions simple and easy in hifi vision.
Vivek

 

[adityapm]

I have reconed several vintage alnico drivers. I always take a note of the gap strenght for record or reference. In atleast 90% cases had found reduced flux value in them. I do remagnetize them before recone. You can never predict or guess that every thing is alright until you measure it and see for yourself.
And as to modulation linearity ..... this is something off topic & are advanced tech talk.
They might not be simple to understand by most of the members in this forum. I am sorry to say this, but this is hard truth. Lets make discussions simple and easy in hifi vision.
Vivek

You are right about your experience with the altecs, as most of the altecs that people retrieved here were from pro installations like the movie theaters etc. mostly, and these were anything but not hard driven. But tannoy co-axials were not the flavour of the same industry the way altecs were, and rather Lomo was the 2nd choice mostly. But again parameter measurements are also needed for serious DIYing, about which I have already mentioned.

About the advanced tech talk observation, I think you should speak for yourself instead of generalizing. Also where is the threshold and who decides that ? As I am going thru the variety of posts here, I find there are lots of curiosity !

Aditya

 

[rbalagopalan]

Yes , Mr Bala is always a helping hand . Eager to listen to it - if i could make a trip to Chennai , before it makes it kerala.

Forgot to puton record, Balagopalan's contribution who made it happen. Our forum rocks.

I just happened to come across this thread to day only. In fact when I had been to the owner of these cabinets at his place for auditioning some of his other items he was briefly telling me that these cabinets are of some interest to Capt. Rajesh. So I keenly inspected it and found that there has been every bit of effort of this gentleman in building up this cabinet and made it so meticulously which Rajesh should never miss.

So after returning to Chennai I talked to Rajesh and explained the quality of the cabinet and the effort involved in building this. Cause this gentlemen who built it has a very very vast knowledge in Audio Gears and has everything in his finger tips. On the approval of Rajesh I organized for the pick up and ensured it is being delivered to him.

In fact the four pin connector which he was searching for was available with this gentlemen as spare and he got the same couriered to him. The whole thanks goes to this gentlemen Mr. Sri Venkatesh.

Very rare to find such personalities.

Thanks

R. Balagopalan

 

[Norton]

Re: A little off-topic



Interesting! I thought no one really bothered too much about large cone coaxial drivers other than Tannoy and KEF kinda oldies.

The problem with large cone coaxial drivers is their inability to cope with fast paced music. If there are any large cone coaxial drivers that can cope with fast transients as well as smaller drivers do, I'd like to build a system around them someday.

Contrary to popular notion, even I feel a solid state amp with a medium damping factor should be used with these large cone driver. Large cones are heavier with higher momentum and hence need greater current to be controlled properly. If not they will add their own signature to the sound as well as will be slow.

Really amazing speakers. Have the 12 reds. Outstanding soundstage and timing. Room filing sound

 

[MaSh]

Really amazing speakers. Have the 12 reds. Outstanding soundstage and timing. Room filing sound

Do post pictures and details of your chain please.

MaSh