Upgrading An Ashdown Cab

[Sharkfinger]

OK, so not exacly in the same league as building one from scratch but wanted a relatively light and compact combo that was mega powerful but wasn't your regular 'class D / rubbish speakers'.

Why this particular combo cab?  Because the amp enclusure is tall and (just about) deep enought to fit my incredible EA iAmp800.

Bought an Ashdown combo off ebay that without the head and away I go.  Measured the internal volume and hit up @stevie for advice on porting.  What a gentleman he is, so patient and helpful. Was going to go for the Faital Pro 15PR400 but he advised me to go for the BMS 15N620.  Who am I to argue? Bought the speaker.

Now, before we go any further, the internal depth is pretty shallow, so that means longer ports.  Really difficult to get 100mm diameter ports that are 150mm deep, so I'm going to have to be inventive.  Stevie advise me to use a plumbing pipe but they don't have a 'lip' on the outside.  Got something else in mind, stay tuned (no pun intended).  

Here we go with the gratuitous pic-fest:

 

Yeah, I know it's a bit blurry but you get the idea.

Before I start, taping the affected area to protect it and get a clean cut.

The ports (on their way) will have an outside diameter of 103mm and this hole cutter's diameter is 102mm.  Gets me most of the way there, should be a nice tight fit or maybe have to sand a bit to get it to fit, we'll see.   

Drew around the cutter to get an idea of where it's safe to smash away....

Cut and pulled away the old ports.

 

 

Put a board on the inside back, as a guide for the drill bit of the cutter.  BTW, there was absolutely  no dampening wadding at all, so there's room for improvement right there (Stevie also advised me on this).

 

Using the cutter disk, marked the centre, so know where to place the drill bit.

 

Here it is after.  Needed to use another bit of wood to 'raise' the guide, as the drill bit was not long enough to reach.  Cordless drill wasn't cutting it (pun inteded), so had to go mains.

So far so good.  Done everything I can right now, have to wait for parts to arrive.

Edited June 4, 2019 by Sharkfinger

[SpondonBassed]

1 hour ago, Sharkfinger said:

Cordless drill wasn't cutting it (pun inteded), so had to go mains.

Was that an 18V drill?  For that large a diameter of hole-cutter you'd need something with a lot of torque and a decent size of grip to hold it steady.

[Sharkfinger]

1 minute ago, SpondonBassed said:

Was that an 18V drill?  For that large a diameter of hole-cutter you'd need something with a lot of torque and a decent size of grip to hold it steady.

As I found out yes. It's only a DIY one, although this is the first time it hasn't been up to any job I've asked of it, including going through solid brick walls on the hammer setting.

S'okay, my mains powered one did the job fairly easily.

[stevie]

This is a great way to get a great sound at minimum cost. This is going to sound fantastic!

I'm intrigued to find out how you solve the port problem.

[Sharkfinger]

14 hours ago, stevie said:

This is a great way to get a great sound at minimum cost. This is going to sound fantastic!

I'm intrigued to find out how you solve the port problem.

Once the speaker is in stock and they send it to me.  Probably still a week away.  The wadding should be on it's way and I can at least get on with that.

[Chienmortbb]

Looking forward to this one. 

[Sharkfinger]

On 06/06/2019 at 17:21, stevie said:

I'm intrigued to find out how you solve the port problem.

Been a bit short on time.  Anyway, was going to try to stick this pipe connector on the end but the external diameter of the connector is too big for the internal diameter of the port tube.  

However, found this on Amazon, which is 5 times more expensive than the one I bought (£15 for 2 delivered) but are exactly the right diameter and depth.  Will need to make the cutout a bit bigger but saves a lot of pissing about and less joints to go wrong.  Just got them today, will have a look tonight or tomorrow so fingers crossed.

[Sharkfinger]

Here is the port as it arrived.  Fab, those 'fins' should help hold it in place.

 

Marking on the back where to cut the slits for the fins.

Somehow managed to move it between marking them so had to go round twice and correct.  Actually did the cuts in the wrong place on the first one, so I double checked on the second as you see below.

Nice tight fit.

Using Gorilla Glue, put some on the fins and a little round the edges and pushed it in.

Both done.

And squirted some down the inside gap and the back and over the fins I can reach.

Next morning.  Turns out Gorilla glue expands.  Who knew? I would have if I'd fully read the instructions.  Works to my advantage here as it's filled the cutout gap.

Not so much advantage here, seems to have forced it way out, even though was lying on it's back to hold the ports in place.

Hasn't stuck firmly to the covering so peels off OK.  Can cut off excess.  Will try to do that tonight.

Edited June 13, 2019 by Sharkfinger

[Si600]

Will they come out again? If it were me, the ports not being flush would annoy me no end. I'd be tempted to redo them but gluing only on the inside and holding them down with a few bricks, but then, you're not me 😉

[Sharkfinger]

28 minutes ago, Si600 said:

Will they come out again? If it were me, the ports not being flush would annoy me no end. I'd be tempted to redo them but gluing only on the inside and holding them down with a few bricks, but then, you're not me 😉

As you can probably tell, I didn't buy the combo for it's pristine looks. Probably would come off again but not worth the effort.

If they don't clean up or there's a noticeable gap between the port and the box, then I might be tempted.  The weight of the combo holding the ports against the box will (hopefully) ensure the gap didn't get too big.  And if there's a tiny line of glue visible between the port and the box?  Well, that's what Sharpies are for

EDIT: Were I to do it again, I would use wood/PVA glue first glue them in place from the outside.  When that hardened, would then use GG on the inside (only) to bond it and fill the gap.

Edited June 13, 2019 by Sharkfinger

[RichardH]

Yes, gorilla glue comes in various types - looks like you have some of the PU stuff there. I wonder whether the ports would knock out - I suspect not, so sharpie time I reckon!

[Sharkfinger]

Right, I've removed the glue over-spill.  Went OK but managed to put a lovely scratch on the port.  No biggie.

Changed position of cable, from near the middle to as far back and to the right as I can, given where I can maneuver the cordless drill from the inside.  Should have done that before the ports, would have been able to get it much further to the right, because now that's in the way. Happen to have a drill bit that's exactly the diameter of the (thick 8mm) cable, so should be a nice air-tight fit.

Now the wadding.  Stevie advised me to get this stuff (furniture padding) but by god it's horrible to work with, especially in a small enclosure.  Very dusty, bits come off and tears apart easily. Wish I'd got the specific speaker wadding.

Spray glue and staple mounted.

Edited June 14, 2019 by Sharkfinger

[fleabag]

I know it's too late but  Stevie's suggestion of plumbing pipe was pretty close. It;s actually ducting pipe to be precise, and although correct that there's no lip like a dedicated bass port off the shelf, it can be sorted.

Screwfix sell 100mm manrose pipe, and they also sell a 100mm joiner. Just cut the joiner off below the lip, and silicone seal that into the pipe and you have a lip.  I did this in my DIY build

 

 

Edited June 14, 2019 by fleabag

[Sharkfinger]

32 minutes ago, fleabag said:

I know it's too late but  Stevie's suggestion of plumbing pipe was pretty close. It;s actually ducting pipe to be precise, and although correct that there's no lip like a dedicated bass port off the shelf, it can be sorted.

Screwfix sell 100mm manrose pipe, and they also sell a 100mm joiner. Just cut the joiner off below the lip, and silicone seal that into the pipe and you have a lip.  I did this in my DIY build

 

I actually bought those very connectors to try to extend the port tubes I bought initially.  They didn't fit those.

Yes, obvious now with hindsight.  Should have read the build diaries!

The piping round the grill is white so might have got away without spraying them.  Oh well....

Silicon sealer.... damn, why didn't I think of that, I even have some.

Edited June 14, 2019 by Sharkfinger

[stevie]

PVC pipe is not the easiest material to glue but silicon sealant does a reasonable job. Wood glue won't stick to PVC at all.

[fleabag]

Yup, silicone worked very nicely for me.

[Sharkfinger]

Managed to spend a bit more time on the project over the last week. 

Want the cable to be 'extendable' in case I need to put an amp on top of the cab (instead of in the amp section of the combo).  This is my method of making sure it doesn't pull on the speaker connection.  Those of you of a nervous disposition look away now, horrible bodge coming up.

Nice solderless connection, nice.

Damn, the speaker won't fit in the cutout.  Didn't see that coming.

A carpenter mate advised me to buy a drum sanding kit from Toolstation.  £9? Sorted.

After about 30 mins and a LOT of dust.  Had to vacuum the inside of the cab too.

Speaker now fits fine and there is even a tiny bit of play.

Edited June 18, 2019 by Sharkfinger

[stevie]

Not a bodge job at all - that looks fine.

I should have warned you about the difference in driver sizes. You almost always have to open the driver hole up when switching from a pressed steel to a cast chassis. My tool of choice for that is the jigsaw.

When were you thinking of connecting your amp?😀

[Sharkfinger]

33 minutes ago, stevie said:

I should have warned you about the difference in driver sizes. You almost always have to open the driver hole up when switching from a pressed steel to a cast chassis. My tool of choice for that is the jigsaw.

Difference wasn't enough to make a jigsaw usable.  Edge of the cutout is also really near the edge of the cab, wouldn't have been able to maneuver the jigsaw round comfortably.  Jigsaw would have been my preference for no other reason than way less dust would have been produced.

33 minutes ago, stevie said:

When were you thinking of connecting your amp?

Will give it a whirl in the next couple of days.  That going well, can actually start gigging it this weekend, as I have enough play in the cable to sit the amp on top.

Haven't figure out how I'm going to fix the amp in there, although my rack mount tray will fit comfortably in there (height-wise), hopefully with the amp.  The holes in the top roughly line up with a standard 19" rack as well.  Would be great if I could just fit a rack mount rail in there and just rack mount my head.

Edited June 18, 2019 by Sharkfinger

[SpondonBassed]

7 hours ago, Sharkfinger said:

Would be great if I could just fit a rack mount rail in there and just rack mount my head.

I'd have thought that was entirely possible.  What's to stop you?  Maybe we can help.

[Sharkfinger]

13 hours ago, SpondonBassed said:

I'd have thought that was entirely possible.  What's to stop you?  Maybe we can help.

Hope so.  Height of gap is only just tall enough with the feet on.  Will not go in there with my rack mount 'kit' (details here).  If I used another rack mount tray, then I would have to find ways of stopping the head sliding around.  Pre-existing holes (which are nicely plugged), turn out not to align with standard 19" rails, so would need to put new holes in, almost right next to them.

If I'm going to muck about with it, I might has well come up with something custom which uses the pre-existing holes and will generally look neater.  Got some ideas about this and I'll start executing these.

Generally, I'm going to make a 'tray' out of 3mm ply, which is almost the entire footprint of the amp-section.  I'm going to make a raised 'bank' all around the amp, to stop it sliding back and forth or side to side.

Then, vertical pillars that line up with the holes but are not quite full height. When I screw them in, the whole thing will be pulled up a few MM against the top of the section and prevent it from moving up and down.

That's the plan.

[Sharkfinger]

On another note, I installed the speakon and gave it a play test.  Not quite gig volume but as loud as my garage will allow.

Long story short, it sounds good! Very clear and even, responds VERY well to EQ tweaks.  I was especially and pleasantly surprised by the high frequency response.  On my amp, I can sweep the highs from 1K to 8K, so I turned it right up and played an open string as I swept up through this range.  

As expected , the greatest tone changes were as I went up to about 3K.  Surprisingly, the changes were still evident as I carried on through to 4K and above, which I really didn't expect from the spec of this speaker.  There was even noticeable changes to tone (though slight) at the very top of 8K!

Will definitely get gigged this weekend.  

Any of you think I should 'run it in' gently or 'drive it like I stole it'?

Edited June 19, 2019 by Sharkfinger

[BassBunny]

If I remember rightly the iAmp has holes to mount rack ears so when faced with a similar problem to you I used some aluminium angle brackets. Similar to these and mounted my amp in the amp slot as normal:

https://www.ebay.co.uk/itm/Aluminium-Corner-Brace-Angle-90-Degree-Bracket/263138777771?var=562137755591&hash=item3d444b1aab:m:ma82AAgBsXb8AQYOEOvy0Tw

I couldn't quickly find a size that could be cut down when just searching eBay, but they are there. Where I got mine from they did about 10 different sizes and I got the widest one I could that required the minimum effort in shortening it. Obviously being aluminium, it's easy to play with. Sprayed them black and bobs your whatsit. I think I've still got them somewhere, I'll dig them out as a picture is worth a 1,000 words.

[Chienmortbb]

1 hour ago, Sharkfinger said:

On another note, I installed the speakon and gave it a play test.  Not quite gig volume but as loud as my garage will allow.

Long story short, it sounds good! Very clear and even, responds VERY well to EQ tweaks.  I was especially and pleasantly surprised by the high frequency response.  On my amp, I can sweep the highs from 1K to 8K, so I turned it right up and played an open string as I swept up through this range.  

As expected , the greatest tone changes were as I went up to about 3K.  Surprisingly, the changes were still evident as I carried on through to 4K and above, which I really didn't expect from the spec of this speaker.  There was even noticeable changes to tone (though slight) at the very top of 8K!

Will definitely get gigged this weekend.  

Any of you think I should 'run it in' gently or 'drive it like I stole it'?

There are some that say run it in and others that say just go for it. Stevie and Phil Starr may have more to say but I would not worry about it. Just use it it will run in by itself. 

[Sharkfinger]

42 minutes ago, BassBunny said:

If I remember rightly the iAmp has holes to mount rack ears so when faced with a similar problem to you I used some aluminium angle brackets. Similar to these and mounted my amp in the amp slot as normal:

https://www.ebay.co.uk/itm/Aluminium-Corner-Brace-Angle-90-Degree-Bracket/263138777771?var=562137755591&hash=item3d444b1aab:m:ma82AAgBsXb8AQYOEOvy0Tw

I couldn't quickly find a size that could be cut down when just searching eBay, but they are there. Where I got mine from they did about 10 different sizes and I got the widest one I could that required the minimum effort in shortening it. Obviously being aluminium, it's easy to play with. Sprayed them black and bobs your whatsit. I think I've still got them somewhere, I'll dig them out as a picture is worth a 1,000 words.

Please do.

I would have thought the bigger problem would be finding screws to fit the current hole thread.  I emailed EA and asked for a replacement rack mount kit but they weren't forthcoming, as it's discontinued.  However, some screws have recently gone missing from the front so I've asked about replacements for these, as well as rack mount screws.