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View Full Version : Spendor - SA1 The Original. bass driver problem



dantheman91
06-05-2012, 12:34
Hi

A friend of mine picked up a pair of these speakers quite cheap. but one has a rattling bass unit and he's wondering weather it can be fixed it could be rubbing on the coil or something. any thoughts on what can be done to them.

The Grand Wazoo
06-05-2012, 13:12
Try taking the bass drivers out, rotating them through 180 deg. & then replacing them. Sometimes gravity wins & the coil is no longer centred in the gap.

dantheman91
06-05-2012, 14:42
Hi

Thanks i will let him know. i had a listen to these speakers last night and when working they sound pretty sweet. i want them :lol:

DSJR
06-05-2012, 17:01
The BC1 is renowned for old off centre drivers rubbing... Good luck with the SA1, which sounded dull with period vinyl, but came to life for a short while in the digital age before being all but replaced by the SA2, a pair of which helped restore my BC2's...

The SA1 had a trimmed smaller version of the BC1 cone I understand. No spares are available (the tooling was all but knackered and junked I understand and for the tiny number of repairs, too costly to replace) and used prices of these sweet old things is rocketing now BC1's and SP1's have gone through the roof in recent times. This is one speaker to use with the grille off, as apparently the grille on these has a hugely negative effect on the Audax tweeter. The tweeter is being re-manufactured now I understand...

Mr Kipling
06-05-2012, 17:07
Hi,

Don't know if it's any help but last year I bought a pair of Celef Domestic IIs off Ebay and when they arrived I found one had a rubbing voicecoil. Removing the driver I was surprised to find the magnesium driver had oxidised and was covered in a white salt - not that that had anything to do with the problem. I tried rotating it 180 degrees, which made no difference. Then, a few weeks ago I thought I'd have another look and found that the spider had actually itself from the cone.

When I get some new glasses I'll have a go at a repair.

Kind Regards,
Stephen

DSJR
06-05-2012, 17:09
Good idea - thanks :)

dantheman91
06-05-2012, 17:16
Hi

Interesting thanks for the help so far guys.

Reid Malenfant
06-05-2012, 17:21
Here's another little suggestion if rotating the driver 180 degrees doesn't cure the problem.

Find out which side of the coil is rubbing & which way you need to shift the coil to avoid it. Assuming the spider is still properly glued to the cone & speaker basket & you know which way you need to shift it, put a tiny amount of impact adhesive onto two of the spider peaks next to each other & allow it to go tacky.

Then carefully squeeze the two together the required amount to free up the voicecoil.

This works a treat, you just need to be careful & plan ahead :)

Mr Kipling
06-05-2012, 17:26
I did mean to say the spider had detached itself from the cone. Sorry.

Kind Regards,
Stephen

Reid Malenfant
06-05-2012, 17:31
I did mean to say the spider had detached itself from the cone. Sorry.
No worries Stephen, I understood what you were trying to get at :)


Good luck with the repair by the way! If you get stuck for adhesive suggestions, start a thread on here & I'm sure you'll get plenty of replies :cool:

DSJR
06-05-2012, 18:21
Don't use Superglue...

Reid Malenfant
06-05-2012, 18:23
Definately not... Some kind of epoxy resin would likely be ideal imo.

dantheman91
06-05-2012, 18:24
Hi

im trying to buy them off my friend but he's not having it. :doh:. i think they have been stored for a long time maybe the need to be used to losen up a bit prehaps

Condition is good but we cant work out the year we're thinking 1968 to 1972 ish i think or maybe earlier.

dantheman91
20-09-2012, 14:14
I might be having these as a project. for a second system.

hifi_dave
20-09-2012, 15:13
Don't give up the Rogers just yet.

dantheman91
20-09-2012, 15:28
No way dave the rogers aint going anyway :eyebrows:.they are sublime. i was just thinking about getting the spendors fix them then flog them.

hifi_dave
20-09-2012, 15:39
Good plan..:)

DSJR
21-09-2012, 19:29
SA1's were late 70's and didn't have the collapsing/reforming white surround of early BC1 drivers. Hope you can get these sorted as if it's a coil fault, you're screwed I'm afraid.

dantheman91
03-12-2012, 15:01
My friend has i think fixed the driver. the cone was too loose. he has used (paint) to fix them.

:mental:

nat8808
05-12-2012, 16:25
The cone was too loose? In what sense? Paint? Sounds like a bodge...

If it was loose in some way, then sounds like the spider had come unstuck.

I've sorted a BC3 bass driver before that was rubbing - the magnet had shifted over time, closing up the gap for the coil on one side. I solved it by gently heating the magnet on an electric hob to soften the glue and then hit with a wooden block and hammer in the right direction until the cone had equal free movement on all sides. I'm hoping the same technique will solve a completely seized driver too as a previously siezed driver I destroyed suffered from the same closed gap problem due to a shifted magnet (only I didn't know it and the coil was pulled appart as I try to force the cone out - was going to be scrapped anyway)

DSJR
05-12-2012, 16:48
The magnets on BC3 drivers are bolted in position aren't they? I suspect it was the coil going off centre, but if what you did sorted it, then kudos to you.

Martyn Miles
09-11-2013, 13:19
I had an ex. BBC pair, with XLR inputs. Well used and with one dodgy Audax tweeter. Falcon Acoustics supplied ( and fitted...) two new voice coil/ domes. They sounded pretty good after those repairs. I bought the SA1s as the BC1s I owned were somewhat bass heavy in my room. The SA1s were eventually replaced by an original pair of Harbeth HL Monitors. All the good points of the BC1s with a better bass end.
The SA1s were good. In my opinion better than the LS3/5as I owned. These have been replaced by Harbeth HL-P3s. They outperform both SA1s and the '3/5as.

DSJR
09-11-2013, 18:38
As documented in an early 80's Choice review, the old SA1's could sound a bit too tubby with vinyl sources, as limited bass extension and a fairly full balance tends to give an artificial 'bloom' with softer toned sources. On digital masters, it was noticed that the SA1mk1 came to life, as a number of ripe-toned speakers did at the time.

The LS3/5A always squeaked, irrespective of what version or who made them. Very much of their time these days IMO. In a direct comparison between the Harbeth LS3/5A and P3ES, using Quad 34/306 and Marantz CD source (one of the humble ones - CD65?), the P3's absolutely trounced the 3/5A, being clearer, better toned and with far superior imaging. The current P3ESR takes this rather further, especially in maximum bass loudness and midrange clarity IMO...

Martyn Miles
10-11-2013, 08:58
I am hoping to sell my P3s to buy a pair of P3ESRs. They must be worth a reasonable amount, considering what people pay for olde LS3/5as...

Martyn Miles
11-11-2013, 16:02
Hi,

Don't know if it's any help but last year I bought a pair of Celef Domestic IIs off Ebay and when they arrived I found one had a rubbing voicecoil. Removing the driver I was surprised to find the magnesium driver had oxidised and was covered in a white salt - not that that had anything to do with the problem. I tried rotating it 180 degrees, which made no difference. Then, a few weeks ago I thought I'd have another look and found that the spider had actually itself from the cone.

When I get some new glasses I'll have a go at a repair.

Kind Regards,
Stephen

I had a KEF B200 which was rubbing on the magnet. It had been storered for years facedown and was ( surprisingly ) slightly better.
I left it in the airing cupboard for a while, upside down from how it had been in the cabinet. It re-centred itself eventually, and worked perfectly after that. I eventually sold it and it's been OK ever since...

DSJR
11-11-2013, 18:12
It's a sad thing, but the 'old fashioned' paper cone and doped concertina cloth surround as used in old Tannoys may end up being the most stable. Some rubberised cone surrounds do seem to go off and harden a bit with age, mid period Spendors (SP1/2, SP2 up until latest ones at least) losing all their bass for example unless treated with one of the brake fluid formulae.

Martyn, Alex has been using the 'DM1's' and although I found them bass light (stiff cone surrounds?), the midrange is spectacular, clear, very tactile and detailed and totally non-peaky. Just thought I'd mention it in passing :)

Sadly, there's no guarantee that old speakers (fifteen years or more) will perform anywhere near their new performance. Crossover caps go off as well as driver suspensions and even if the crossovers are ok still, the drivers do alter as the years roll on... I speak as an owner of forty year old and twenty four year old speakers which are both in regular use (the forty year old pair do have newer bass/mid drivers, which were checked by Spendor's main designer before he sold them to me)