Help with WinISD, please?

[geoffbyrne]

Cab: made from standard ply (18mm?)

Width: 620

Length: 500

Height: 540

4 x vents: 100mm with tubes approx 200mm

Eminence 2515 driver





I'm hopeless with this software - thanks in advance.

G.

[Balcro]

Hi Geoff,

I presume you want to check the tuning and the installed driver or the driver to be fitted, is an Eminence Basslite 2515. Is that correct? Are those ports really 200 mm deep?

Balcro.

[geoffbyrne]

Hi Balcro, thanks for the help. Yes, all the usual stuff. As for the ports, I can't measure them as (a) the cab isn't here, it's at the studio and ( I'd need to take the grill off.

I know the guy who sold me the empty cab told me it was tuned pretty low. They are certainly 6", 150mm.

That's the 2515 in the pic - a lot better than the 200W Celestion that was in it before. I know the 2515 needs a big cab to get the best from it and to my ear it certainly delivers - I just want to see what the figures & charts say.

Many thanks.

G.

[Bill Fitzmaurice]

[quote name='geoffbyrne' timestamp='1395350204' post='2401542']
I know the guy who sold me the empty cab told me it was tuned pretty low.
[/quote]If they're 200mm it's not tuned low, it's tuned high, around 50Hz. They should be no less than 250mm.

[geoffbyrne]

I suppose I'll need to take the grill off......

G.

[Balcro]

Hello Geoff,

I ran the parameters of the C2515 (2014) through winISD and quite closely matched Eminence's own "Cabinet design" for a large vented cab - (3.9 cu.ft).

See here: - http://www.eminence.com/pdf/Basslite_C2515_cab.pdf

To my mind the mix of large cab and this Basslite is not a marriage made in heaven, but the
Basslite is flexible in it's volume requirements. Power handling dips to just over 100 watts at 70Hz but at the same time the driver is very efficient. At that frequency with a 100 watt input it is putting out around 119dB!! Loud!

If the internal volume is reduced to 91 litres, power handling rises to a minimum of 120 watts. Output still exceeded 119dB @ approx 78Hz. In either case I set the tuning @ 46Hz but there was no visible difference in overall frequency response - big boost in the low bass - 80 - 160Hz.

By my calculations your potential cab has an internal volume of about 121 litres. It'll work fine in nearly all situations, but the indications are that it has it's technical limitations. I'll post some graph pictures later this evening.

Balcro

[geoffbyrne]

Very interesting.

I went over to the studio this morning & took off the grill - it turns out the tubes are 165mm!! Less than I thought. Could you maybe plug that in, when you get the chance, and maybe suggest to me what length of tube may be optimal here - I expected them to be 200mm and Bill suggests 250.

I have to say that the cab sounds absolutely great to my ears - I'm a kind of small bass boost, medium low-mids boost, mild treble-cut kind of guy. Lop-sided frown, if you like graphic EQ.

Looking forward to the graphs.

I forgot to mention the cab will be driven by either an Ashdown MAG 400 (UK - 465W@4 Ohms) or an Ashdown MiBass 550.


Apropos your 'not in heaven' opinion - I have a smaller cab containing a Kappalite 3015 - is W=460, D=340 & H=500. It has two small ports 75mm wide and tubes 120 deep. Would it be worthwhile swapping the drivers? I also have a Celestion K15 200W kicking around.

It was my understanding that 2515s needed a larger volume cab to deliver.

G.

Edited March 21, 2014 by geoffbyrne

[JTUK]

Good work, Balcro.

[Bill Fitzmaurice]

[quote name='Balcro' timestamp='1395407183' post='2402104']
I ran the parameters of the C2515 (2014) through winISD and quite closely matched Eminence's own "Cabinet design" for a large vented cab - (3.9 cu.ft).
See here: - [url="http://www.eminence.com/pdf/Basslite_C2515_cab.pdf"]http://www.eminence....e_C2515_cab.pdf[/url]

[/quote]He didn't say if he had a Basslite or Deltalite II, which are quite different. In may event the Basslite models best around 400L tuned to 33Hz, so it's a bit of an odd duck for bass unless you run drop tuned. 100L technically gives more power handling, but the loss in sensitivity offsets that. Maximum SPL remains the same above 42Hz, but it's less below that. Again, moot with a four stringer. The Deltalite in 150L with 44Hz tuning is much better than the Basslite in any configuration for four string. IMO the Basslite has no redeeming quailties save the 4 ohm impedance, which you might need running a single cab with some valve amps.

[Balcro]

Hi Geoff,

Well spotted Bill.

It looks like you need to double check the exact description of the drive unit. Are there any other labels or codes apart from "2515" attached to or printed on the chassis. Let us know.

Balcro.

Edited March 21, 2014 by Balcro

[geoffbyrne]

All I can tell you is it is the Neo driver & it's 8 ohms, my understanding being it is the Deltalite - any more info needed & I'll have to take it out the cab. And I play 5 strings almost exclusively - don't often hit low B, but low D crops up quite often.

G.

p.s. I've just looked at pics of the Basslite & the Deltalite II on Google, and it's defo the Deltalite.

Edited March 21, 2014 by geoffbyrne

[Balcro]

Hi Geoff,

I've just re-run winISD with the Deltalite parameters. Looks like a nice fit at 120 litres. If you can give me the exact internal diameter of the port(s) I'll check it again.

Balcro.

[Bill Fitzmaurice]

[quote name='geoffbyrne' timestamp='1395425546' post='2402402']
I've just looked at pics of the Basslite & the Deltalite II on Google, and it's defo the Deltalite.
[/quote]Visually they're identical, they have the same frame. The only way to be sure is to measure the DC resistance. The Basslite is about 3.7 ohms, the Deltalite II about 5.3 ohms.

[geoffbyrne]

[quote name='Bill Fitzmaurice' timestamp='1395434041' post='2402548']
Visually they're identical, they have the same frame. The only way to be sure is to measure the DC resistance. The Basslite is about 3.7 ohms, the Deltalite II about 5.3 ohms.
[/quote]

I've found the original PMs for the deal - it's a Deltalite II.

[geoffbyrne]

[quote name='Balcro' timestamp='1395433532' post='2402540']
Hi Geoff,

I've just re-run winISD with the Deltalite parameters. Looks like a nice fit at 120 litres. If you can give me the exact internal diameter of the port(s) I'll check it again.

Balcro.
[/quote]

The 4 ports are 100mm diameter and the tubes are 165mm.

You're doing a great job, mate.

G.

[Balcro]

[quote name='geoffbyrne' timestamp='1395435188' post='2402567']
The 4 ports are 100mm diameter and the tubes are 165mm.

You're doing a great job, mate.

G.
[/quote]

Your welcome.

Gotta Dash, back after 11.30

[Balcro]

Hello Geoff,

These graphs show the frequency response for your existing set-up with the Deltalite. I've only used 3 of the ports. Using 4 sent the port length to over 24cm.

Edited March 21, 2014 by Balcro

[geoffbyrne]

Gosh that looks impressive!!! What effect would using the 4 ports have? Or is it a limitation of the software?

Anyway, it looks as good as it sounds to my ear.

When I use it conjunction with the 3015 (which is a bit more middy & brighter) I get about 800 watts capability and a very full sound. With my MAG400, that's my heavy rig - I also have a GB NX212 which I use with my MiBASS 550 as my light rig. I don't think it's just as loud or as bassy as the 15s, but it's a lot more manageable

G..

[Balcro]

Good morning Geoff,

Ah! The effect of using 4 ports - There's a very small boost, maybe 0.2 of a decibel, to that flattened frequency response curve between 100 - 200Hz. Minimum power handling dips by about 0.4 watts, cone excursion is unchanged, and Port air velocity (assuming a 150watt input) drops from an already low 13.5 to about 10.5 (not sure of the unit in this case). These changes are clearly of little
importance.

However, using 4 ports puts up the required port length to maintain the same tuning; it rises to 24.4cm, which means you would have to lengthen all 4 ports. It's easier to just cap off one port.

Putting in 150 watts as a test input, winISD calculates that the output at 100Hz will be about 123dB!! Extremely loud. You're also within the 4.8mm xmax limit @ 73Hz (see the red horizontal line). It's surprising how little input you need to make a big noise. The middle picture shows the power handling with the revised internal volume.

The 3rd pic below shows the cone excursion. Xmax is exceeded at about 41Hz, but unless you're going to play at deafening sound levels with a full-on octaver, you'll probably never reach it.

I've re-checked the volume figures overnight and have now calculated the internal volume to be 123.6 litres. See the l/h picture. This has had a negligible effect on the curves.

Enjoy the noise.
Balcro.

Edited March 22, 2014 by Balcro

[geoffbyrne]

Many, many thanks for doing this. I owe you a pint (or three!) and much respect.

So, to sum up, the Eminence Deltalite II 2515 works very well in this cab, but would probably benefit from having one of the ports blocked off - right?

G.

[Balcro]

Hi Geoff,

That's correct. Just cover the end of the port on the inside.

Balcro.

[Bill Fitzmaurice]

[quote name='Balcro' timestamp='1395509673' post='2403250']
Just cover the end of the port on the inside.
[/quote]On the outside, so that the air volume within the duct contributes to that of the enclosure.

BTW Balcro, move up to the W7 version of WinISD, there are a lot more options, including max power, max SPL, and port velocity.

Edited March 22, 2014 by Bill Fitzmaurice

[Balcro]

[quote name='Bill Fitzmaurice' timestamp='1395509842' post='2403254']
On the outside, so that the air volume within the duct contributes to that of the enclosure.

BTW Balcro, move up to the W7 version of WinISD, there are a lot more options, including max power, max SPL, and port velocity.
[/quote]

Hi Bill,

I understand the option, but I advised on an inside mounting as the volume taken up by the port has already been accounted for in the enclosure net volume calculation of 123.6 litres and Eminence's recommendation is for 119 litres. Still, it's only a gain of 1.2 litres, so won't make a great difference. Putting it on the outside may well be practically & cosmetically easier with no chance of damaging the port tube.

Thanks for the tip about the Windows 7 version. I'll look it up. It's a couple of months since visiting Linearteam, being an XP luddite.

Regards,

Balcro.

[Bill Fitzmaurice]

[quote name='Balcro' timestamp='1395512274' post='2403279']
Hi Bill,

I understand the option, but I advised on an inside mounting as the volume taken up by the port has already been accounted for in the enclosure net volume calculation of 123.6 litres and Eminence's recommendation is for 119 litres. Still, it's only a gain of 1.2 litres, so won't make a great difference. Putting it on the outside may well be practically & cosmetically easier with no chance of damaging the port tube. At 119L with the same tuning you lose 2dB from 40 to 50Hz, and that's right where I don't want to lose anything.
As for XP, support for it ends in three weeks. Now is a good time to jump to W7, as any computers still on the shelf still loaded with it are on sale.
Thanks for the tip about the Windows 7 version. I'll look it up. It's a couple of months since visiting Linearteam, being an XP luddite.
[/quote]My WinISD defaults to a QB3 alignment for the Deltalite II 2515, at 157L and 44Hz. 119L loses 2dB from 40-50Hz. XP support ends in three weeks, time to move on.

[Balcro]

[quote name='Bill Fitzmaurice' timestamp='1395516130' post='2403328']
My WinISD defaults to a QB3 alignment for the Deltalite II 2515, at 157L and 44Hz. 119L loses 2dB from 40-50Hz. XP support ends in three weeks, time to move on.
[/quote]

I'm running winISD Pro Alpha v 0.50a7 and I get an identical result. Quite why Eminence recommend, an enclosure volume between 51 & 119 litres I don't know, but they do. I only found 1 version download on the Linearteam web-site, but I'll try it on my other computer with W7.

Balcro.