advertisement


Gales : how good can they get ?

nws56

nws56

pfm Member
No, it's not another restoration story. The Mr Tibbs thread on here has already covered that in detail.
But what no-one has done has upgrade an already 'restored' pair incrementally, finding out the most effective areas to improve.
Some of these will cost absolutely nothing.
Some may stray into boutique territory.
Some may be an utter waste of time - both mine and yours if you stick around to read about it.
But come with me anyway, gentle reader, and hand in trembling hand we will find out together.


Stage 1 : External crossover - Rating * - Value for money rating 10/10
2 :​
3 :
4 :
5 :
6 :
7 :
8 :
9 :
10 :


From the front you cannot tell that the crossover is mounted externally.


A plywood blanking plate was glued to a replacement crossover board inside the speaker.


M6 threaded rod was hammered in to facilitate mounting the new crossover board.


The existing pc board has been temporarily lashed to the new board, but will eventually be discarded when point to point wiring is implemented.
 
Please could you enlightenment the good readers why moving the board to the outside should make a 10/10 improvement?

Is it because the board is modified with different components?
Or is it claustrophobic and prefers it freedom before it will perform?
Or maybe another reason...
 
If you are going to the lengths of moving the crossovers to the outside, then you need to fit them into a separate enclosure and house it elsewhere, otherwise there is no advantage. The only reason I can think of to move the crossovers is to remove them from the vibration path. There is no point that I can think of, in attaching the crossover to the outside of the cabinet. This applies whether or not you are reusing the old crossovers, or fitting new ones.
 
Stage 1 - external crossover. Rating * Value for money 10/10

I had done this before on a different pair of speakers with great results, so expected similar with these.
And seeing how close the big inductor was to the magnet of the bass driver was added incentive.
Also, those incremental upgrades I was planning would be much easier on an external crossover.
And if it didn't work out, it could all be put back again and no one would be the wiser.

So,what difference was there ?
Smoother , cleaner, less edgy. Easier to listen to. Not the overwhelmingly better sound I'd got from the previous occasion I'd done this, but worthwhile doing.
I reckoned a one star rating was fair, and since it didn't cost anything, the vfm is appropriate.
Wife said it sounded 'kinder' . Kinda better or kinda worse I enquired, but she refused to elaborate. I left it at that.
 
Must admit I'm a bit sceptical, but don't let us miseries on PFM put you off.

I do think you should be careful with those "wire-wrap" connections though. OTOH you are not a fully paid up member of the DIY room until you have produced a few magic smoke signals :D
 
Stage 2 - internal rewire. Rating * * * Value for money 9/10

If you scrutinize the pictures above you will see those thin original coloured wires peeping through 5mm holes in that blanking plate. Notice the black and red ones ( for the tweeter ) are even thinner.
No one got upset about this in the 70's. Would the Gales respond to thicker cables ?
Neotech NES 5005 is a no frills, dirt cheap 2.5mm option from the Collective - couldn't face wrestling with nac A5 again.
An obvious improvement straight away; every parameter you can think of was better. A big, bold muscular sound and stronger 3D image.
It made the previous sound - which I had liked ! - seem quite aneamic. Gained smoothness, cohesion and bass weight after some days of use.
Did not change the essential character of these speakers, just gave you more of it. Well pleased with this.
It seems that Fat Wires Matter.
 
Swap all your caps for Russian K73-16. 250V or so should do it (I think) , match either side as closely as possible. Ditch those very nasty cement resistors and go with Kiwame, if you can get away with 5W, otherwise use Mills.

This is just what I have found, to do things properly you need to measure your drivers and match the caps and resistor values accordingly. Good luck
 
Dan K said:
Swap all your caps for Russian K73-16. 250V or so should do it (I think) , match either side as closely as possible. Ditch those very nasty cement resistors and go with Kiwame, if you can get away with 5W, otherwise use Mills.

This is just what I have found, to do things properly you need to measure your drivers and match the caps and resistor values accordingly. Good luck
Click to expand...
Unfortunately Dan, I don't have the level of expertise ( or equipment ) necessary to measure components and drive units. I had a hard enough time persuading the Collective to match some big caps to be slightly over rated value.
Suspect they just shoved the first ones to be reached into a bag...
I am what serious electronic engineers disparagingly refer to as a 'parts swapper', not really grasping the nature of what I'm tinkering with.
This hasn't stopped my enjoyment of doing it one little bit. Funny, that.
I've already acquired all of the caps I need to replace the lot, but will research those Russians. The resistors are awaiting the change - but there is still work to be done on the point to point wiring and star grounding beforehand .
Thank you for your interest.
 
I rebuilt a pair of Gales a while back mine had failed surrounds and the resisters were literally burnt out. once I rebuilt the drivers and replaced the resisters I did a series of mods to the crossovers.
The celestion tweeter is quite smooth sounding especially compared to the competitors of the era and if it has a fault it's more to do with detail resolution.Fancy caps are a waste of time here good quality standard polypropylene is fine I used solen as they have the exact values required.I wouldn't use carbon resisters or mox use the excellent Jantzen wire wounds not to expensive and top quality. The biggest improvement is to be had with the inductors, the originals are top quality for the era but are hand wound on plastic formers and held together with insulating tape.They are microphonic particularly the big bass coil, the bass is only a first order roll off and play's well into the mid range.I found with mine as the volume increased I would get a kind of distortion creeping in, thinking about it I wondered if that coil was being affected by vibration so I bought a pair of Jantzen coils which are of similar resistance and glued together.This made the biggest difference to anything else I tried no change with volume now and there's more detail as well probably the better quality copper.Finally I hard wired them and no fuses, with glued coils you can leave the crossover in the box as well.
 
I'd keep them standard but with Solen caps and better quality resistors (the originals are terrible and prone to failure). I've found they work best on wobbly stands where the mass of the cabinet does the work without constraint. The chrome replica stands are a big jump up from anything else I've tried! Even in 'standard' trim, when working properly and well fed these things are still awesome music makers :)
 
GWM said:
I rebuilt a pair of Gales a while back mine had failed surrounds and the resisters were literally burnt out. once I rebuilt the drivers and replaced the resisters I did a series of mods to the crossovers.
The celestion tweeter is quite smooth sounding especially compared to the competitors of the era and if it has a fault it's more to do with detail resolution.Fancy caps are a waste of time here good quality standard polypropylene is fine I used solen as they have the exact values required.I wouldn't use carbon resisters or mox use the excellent Jantzen wire wounds not to expensive and top quality. The biggest improvement is to be had with the inductors, the originals are top quality for the era but are hand wound on plastic formers and held together with insulating tape.They are microphonic particularly the big bass coil, the bass is only a first order roll off and play's well into the mid range.I found with mine as the volume increased I would get a kind of distortion creeping in, thinking about it I wondered if that coil was being affected by vibration so I bought a pair of Jantzen coils which are of similar resistance and glued together.This made the biggest difference to anything else I tried no change with volume now and there's more detail as well probably the better quality copper.Finally I hard wired them and no fuses, with glued coils you can leave the crossover in the box as well.
Click to expand...
That is very interesting. My DIY 3 ways use 2.6mH on the bass for 6dB rolloff. NOT set in varnish so must try this.
 
a.palfreyman said:
That is very interesting. My DIY 3 ways use 2.6mH on the bass for 6dB rolloff. NOT set in varnish so must try this.
Click to expand...
Yes well worth doing, not just about mechanical coupling from the drivers but the signal going through them, also keep away from any metal parts not just ferrous ones.Personally I think the coils are were the money should be spent on crossovers not so much on fancy caps.
 
GWM said:
I rebuilt a pair of Gales a while back mine had failed surrounds and the resisters were literally burnt out. once I rebuilt the drivers and replaced the resisters I did a series of mods to the crossovers.
The celestion tweeter is quite smooth sounding especially compared to the competitors of the era and if it has a fault it's more to do with detail resolution.Fancy caps are a waste of time here good quality standard polypropylene is fine I used solen as they have the exact values required.I wouldn't use carbon resisters or mox use the excellent Jantzen wire wounds not to expensive and top quality. The biggest improvement is to be had with the inductors, the originals are top quality for the era but are hand wound on plastic formers and held together with insulating tape.They are microphonic particularly the big bass coil, the bass is only a first order roll off and play's well into the mid range.I found with mine as the volume increased I would get a kind of distortion creeping in, thinking about it I wondered if that coil was being affected by vibration so I bought a pair of Jantzen coils which are of similar resistance and glued together.This made the biggest difference to anything else I tried no change with volume now and there's more detail as well probably the better quality copper.Finally I hard wired them and no fuses, with glued coils you can leave the crossover in the box as well.
Click to expand...
Hello Geoff,

I remember reading what you did with those 401c's, and I had in mind to replace those inductors accordingly.
Unfortunately I can not find the dcr value of them ; I did in fact pm you regarding these values back in the summer...
Already have the Jantzen resistors waiting their turn to be fitted.
The previous restorer had already bypassed the pots and fuses with those sandcast things so despised by many.
 
I found some notes I made the coils in my gales measured 3.12/3.01 mH and around 0.9 DCR.This is of course with a standard meter so not sure how accurate it is at measuring inductors.There is/was a circuit diagram on line of the Gale crossover that list this inductor as 3.3mH but no DCR value so I bought some inductors at 3.3 and the nearest DCR from Janssen,go higher DCR if you can't find exact match the Gales all ready have a pretty low value here.
 
Insidently I kept the pots in place just cleaned them out, they are use full for fine tuning and don't seem to negatively affect the sound.I did by/wire mine replacing the fuses with speaker posts so I could power the base units separately.
 
You must log in or register to reply here.


advertisement


Back
Top