Problems with Tecamp Puma 100 and help with WinISD

[pete.young]

Used my Tecamp Puma 110 last night for a not-very loud gig and it started making buzzing noises anywhere below B, second fret on A-string.

Gain was about 1 O clock, clip light off, master volume at 12 O clock, so it wasn't a case of everything maxed out. Bass is a passive Precision.

Looking at it this morning, gentle pressure on the driver with fingers and I can hear a rubbing noise, as though something is sticking in the voice coil. I also notice that the cooling fan in the amp doesn't come on when the power is first switched on, so I think it may have failed. I'm guessing that the increase in temperature may have led to a failure of the voice coil.

The amp is out of warranty so it looks as though I'll need to fix it myself. Assuming that I can remove and replace the failed fan, I'm going to need another driver. The existing unit is a Sica code Z006899 . This model appears to be discontinued. I've emailed SICA to ask for a data sheet. The replacement appears to be a Z006900 , or model no. 10L 2,5 SL . The only Thiele-Small parameters listed on the website for the updated model are:

Fs 54 hz
Qts 0,33
Vas 43.8
SpL 96.3

I'm trying to model the enclosure in WinISD without really knowing what I'm doing: the enclosure size is fairly small:

Width 400mm
Height 300mm
Depth 190mm

There are two rectangular ports extending out of the bottom of the enclosure (under where the amp sits) These are each 190mm wide by 50mm high and extend by 120mm from the enclosure. There's also a tweeter box taking up space, 110x100x70 - not sure if that's a significant factor.

I'd welcome suggestions for a replacement driver - the Eminence Deltalite II 2510 seems like a reasonable match

[JTUK]

Hmm.. this is a common problem IMV..but am not sure how bespoke that speaker is...but since you say it is out of production the problem is the same.
You might be in a better position getting info from the maker..and also sorcing a recone kit as it does indeed sound like the coil has
given up. You can try the usual speaker/cone repairers but they will need to have the cone kit from somewhere. I had this problem with PAS which was a great speaker rated at 175watts for 10" but no one could get the cone..and if they used their own assemblies, could not garauntee anymore than 100 watts..if that. I have no idea how PAS squeezed 175watt out of it then, but make of that, what you can..!!!!!!!

If you are techical..you might consider a swap out speaker from a current line but you may need to remodel the cab somewhat..and then that still seems little like trial and error to me.

Gone are the days of just bunging a replacement speaker in the box..but since you have only a single you could match up the porting size and see how that works. At least you don't have another speaker in the cab to have to balance with and that could have complicated things.

It seems you have no choice..I recently tracked down a replacement speaker and my chassis is still current and available via import..and that is the best solution but not an option here. I will be interested in how this experiment turns out

The deltalite 2510 was the speaker I ended up using..and I wasn't convinced, but others say it worked great as a replacement PAS.

Edited April 10, 2011 by JTUK

[stevie]

It sounds like you're going to have to do more than just replace the fan and speaker. I think there's a good chance the faulty fan may have taken out your output transistors.

Edited April 10, 2011 by stevie

[pete.young]

Stevie, why do you think that? It's still fine above 'C' and is OK at lower volumes. I'd expect a transistor to either work or not.

[icastle]

According to the specification, the cooling fan is temperature controlled, suggesting that it doesn't do anything until a particular temperature is reached.

[stevie]

[quote name='pete.young' post='1194999' date='Apr 10 2011, 08:17 PM']Stevie, why do you think that? It's still fine above 'C' and is OK at lower volumes. I'd expect a transistor to either work or not.[/quote]
Oops, sorry... (hitting myself over the head) I didn't read carefully enough.

As far as replacement drivers are concerned, I wouldn't worry about modelling them, just get something close to the Spica specification. For a budget 10 with a ceramic magnet, one of the Fane Sovereigns would be good. If you want some real quality, look at the Celestion NTR10-2520E - at a price (although there are more expensive options around). LawrenceH has been trying that one out recently and maybe he'll catch this thread.
I wouldn't bother with the Deltalite personally - the Celestion is a much better driver at not much more money.

[pete.young]

[quote name='icastle' post='1195208' date='Apr 10 2011, 11:13 PM']According to the specification, the cooling fan is temperature controlled, suggesting that it doesn't do anything until a particular temperature is reached.[/quote]
That's true, but my understanding is that when you first power up the amp, the fan runs for a few seconds as a check that it's working. That doesn't seem to be happening.

[pete.young]

[quote name='stevie' post='1195410' date='Apr 11 2011, 09:14 AM']Oops, sorry... (hitting myself over the head) I didn't read carefully enough.[/quote]

No worries! It's something I can easily test and should probably do anyhoo before I completely right off the driver - I can disconnect the internal and plug the extension into a suitable cab.

Thanks for the recommendation, I'll check out the Celestion. So far Sica haven't responded to my request for a data sheet, so getting a recone kit out of them might be a challenge.

[stevie]

Here's some info on the Sica: [url="http://www.teamaudio.fr/en/sica-10-l-2-5-sl-8ohm.html"]http://www.teamaudio.fr/en/sica-10-l-2-5-sl-8ohm.html[/url]. Cost around £80. It looks quite good as far as you can tell from just the specs and Sica do make some quality drivers (Ashdown use some of their cheaper models). It's probably worth rescuing if you can get hold of a recone kit and can put up with the hassle of organizing it.

The spec says foam surround. Is that right? If so, you will find it hard to get a replacement that will go as low, although the Celestion I recommended will do it.

I read that this driver is available in a number of impedances - so check whether you have a 4- or 8-ohm version before getting a replacement. It might also be worthwhile dropping Tecamp an email.

[LawrenceH]

I had a Puma 110 briefly and took some piccies of the inside, including speaker. The Sica model used is just a pressed steel chassis, it is indeed essentially their 'standard lite' model as you've been told. They do a 'premium' version with a cast chassis, and tbh I'd expect a cast chassis on a combo this expensive. Modelling the Tecamp to give an idea of what will work as a replacement is a bit complicated because the port is a shelf-type, which WinISD doesn't cope with - I'd never designed a speaker with modern software before when I tried, and came unstuck because of this (used to just do it the old fashioned way, measuring the tuning and adjusting empirically). You're probably best off as Stevie says just using the TS parameters of the Standard Lite and looking for something in the same ballpark. The internal volume of the 110 is pretty titchy so you want one that works well in a small box.

What I didn't like about the 110 combo was the amount of overlap between the upper end of the woofer and the midrange unit, thanks to the cab only employing a simple high-pass filter cap for the mid rather than a proper 2-way crossover. It makes the midrange rather harsh. The Puma 112 I replaced it with didn't have this problem, presumably because the 12" unit doesn't have such a high frequency response so there is less overlap despite the simple cap crossover. For this reason, and the fact it likes a big box for a 10" unit, I'd suggest the Deltalite II is NOT a great choice in this cab - it has a whopping great peak around 2.5k-ish that will sound nasty against that 4" midrange. Again as Stevie has said I've been playing with the Celestion cast chassis neos, though actually the NTR10-2520D, not E. This has a very smooth extended mid-range and is happier in a smaller box than the Deltalite, and is probably more similar to the Sica driver but considerably better quality. Compared to the Deltalite II in a small box, it is less sensitive in the upper bass region but compensates by going lower and taking more power before you hit the excursion limit (Xlim is 12mm compared to 8 on the Deltalite). BUT - because you have the mid-range unit in the 110, then the NTR10-2520E might be a better choice. The bass end in practice will behave very similarly, but it rolls off lower down (less nasty overlap with your mid driver) and has even greater linear excursion than the 'D' model so you will get very tightly controlled bass right up to the performance limit of the cab (Xlim still fixed at 12mm). It'll most likely sound a bit less bassy than the Sica unit run flat, but will actually go louder and deeper.

You could also try B&C, Faital or Beyma but they will be more expensive units - the Celestion are on offer at £90 here, and if they're as good as the 'D' units well worth it IMO: [url="http://www.lean-business.co.uk/eshop/celestion-ntr102520e-10%C3%82%E2%80%9D-250w-neo-pa-driver-p-526.html"]http://www.lean-business.co.uk/eshop/celes...iver-p-526.html[/url]

I'd definitely take the Celestion over the Sica Standard Lite model, but I'd guess the Premium Lite would also be worth a shout, though I haven't checked the spec. The Eminence units are good for the money, but based on my experience the Celestions are better if you're after even tone in a small box. They just stay so clean for so long!

Edited April 11, 2011 by LawrenceH

[pete.young]

[quote name='stevie' post='1196285' date='Apr 11 2011, 10:01 PM']I read that this driver is available in a number of impedances - so check whether you have a 4- or 8-ohm version before getting a replacement. It might also be worthwhile dropping Tecamp an email.[/quote]

I did send an email to Tecamp, and I've had a hugely positive reply today suggesting that they think the tweeter/midrange unit is the problem and asking me to send the unit back to them.

Which I'm going to do, when I get 10 minutes to dig the box out of the loft.

Many thanks to everyone for your helpful comments: i'll let you know how it pans out.

[LukeFRC]

I dealt with them with a broken tweeter switch on a tech soundsystems cab, they are brilliant to deal with

[pete.young]

An update on this: Tecamp have been brilliant and fixed the amp in less time than it took DHL to turn up and collect it. It's on its way back to me.

They agreed that the driver had failed and fitted a new one for 80 Euros plus tax - not sure which model they used yet.

Given that this is the second driver that has failed (the first one was fixed under warranty), I'm not going to waste any more money on Sica. The next time it blows I'll follow stevie and LawrenceH's suggestion and look for a Celestion. Thanks to everyone for the helpful suggestions.

Edited May 1, 2011 by pete.young