Newark sale on drivers

jr@mac

Some nice stuff at nice prices right now at Newark:

Dynavox 6" Honeycomb midwoofer - $34.14

Dynavox 5" Honeycomb midwoofer - $31.71

Dynavox 5-1/4" Poly midwoofer - $29.20

MCM Audio Select:

1" Large Flange aluminum dome tweeter - $9.15

8" Die Cast Woofer (the KB model, 7.5mm Xmax) - $26.42

3" Die Cast Woofer (KB series, ultra low distortion) - $12.88

1" Silk Dome tweeter - $8.72. Both this tweeter and the aluminum dome use a well designed rear chamber, are very low distortion above 2K or so. 

6.5" Die Cast Woofer (KB model, 7.5mm Xmax) - $21.13

4" Aluminum Cone Woofer - $10.49

4" Die Cast Woofer (KB Series, another very low distortion driver) - $15.86

In addition, it looks like quite a few of their more basic drivers are on sale, as well. The drivers that are essentially identical to the GRS poly drivers at PE, for example. 

PWRRYD

Wow!  Those 8" die cast KB woofers (55-5670) model really great.  A pair of them in parallel in  ~50 Liters vented would make a killer TMWW.

PWRRYD

Almost identical bass performance to the RS225P-8A for less than half the price!

Must resist... must resist...  must resist...

Ah shucks...  can't resist!

jr@mac

Add the extra excursion the KB offers and it is a no-brainer, to be honest.

ani_101

anyone have measurements for the 8" KB and measured T/S Specs?

jr@mac

Javad, Duane, and Chuck I believe all have first hand experience with them.

I am seeing a small, sealed enclosure using a pair of each 8" per, in an opposed alignment, with a plate amp utilizing some EQ. Take advantage of the long throw. 

Wolf

I'm still working on my 55-5665 Iso build...

jr@mac

I'll not be isobarically loading them - although that would be fun. 

dcibel

I'd really like to try those Dynavox honeycomb drivers, they look pretty cool, but there's very little info at all online about them beyond the spec sheet.

PWRRYD

Bought an eight pack....  four 8's and four 4's.

Tom_S

Sadly, I'm out of speaker shelf space. I'll have to live vicariously through you Craig. But if there are any amazing deals in Ankeny....

jr@mac

Tom_S said:

Sadly, I'm out of speaker shelf space. I'll have to live vicariously through you Craig. But if there are any amazing deals in Ankeny....

There should be...

PWRRYD

Ditto

PWRRYD

Ani,

My delivery from Newark is supposed to arrive today.  If you would like I will bring one of the 8's to Ankeny.  You can bring your laptop and DATS and grab the real T/S parameters.  Bring some blue painter's tape and a stack of nickels for the added mass test.

ani_101

Thanks Craig! unfortunately, I only have my work laptop with me now, and I can't install anything on it, so i won't be able to measure the T/S specs. I do my measurements and sim work on a dedicated desktop loaded with windows 2007!!! it's an old machine sitting around doing nothing, so it plays streaming services and measurement and simulation s/w...

Waiting for this thanksgiving to buy a shiny new device... but the good thin light ones are soooo expensive

ani_101

Depending on how cheaply i can get by at IOWA (I always seem to end up with drivers that i don't need and then buy more drivers to complement those, use neither and buy new ones for the build), I might just get a few...

PWRRYD

I'll bring it anyway.  That way you or anyone else can grope it.

Tom_S

Craig - I can bring my LIMP setup if you can bring the tape & some change. 

PWRRYD

10-4

ani_101

Thanks Craig and Tom... The Manufacturer T/S specs models great, but the actual always tends to be a bit off... !

I'll get the tape and change!!!

PWRRYD

I'll bring my little digital scale.

PWRRYD

MCM drivers arrived as expected.  Just for fun I'm breaking one 8" in right now with 60 Hz at xmax.  I will bring another still in its unopened box to measure for comparison.

Tom_S

I just tested my LIMP rig - still works like charm! See you tomorrow!

jr@mac

I will be experimenting with added mass on the MCM 8". At $26, I won't be out too much if I screw them up. 

Tom_S

Here are the results from the our attempts in Ankeny. I'll be curious to see how the noise level in the room impacted the measurement.

Fs  = 35.62 Hz

Re  = 6.49 ohms[dc]

Le  = 236.44 uH

L2  = 282.15 uH

R2  = 6.90 ohms

Qt  = 0.33

Qes = 0.44

Qms = 1.36

Mms = 19.37 grams

Rms = 3.175131 kg/s

Cms = 0.001031 m/N

Vas = 66.21 liters

Sd= 213.82 cm^2

Bl  = 7.975881 Tm

ETA = 0.65 %

Lp(2.83V/1m) = 91.14 dB

Added Mass Method:

Added mass = 25.30 grams

Diameter= 16.50 cm

Tom_S

-- and we were guessing, not measuring the cone diameter.

Kornbread

Needed to get some boxes out of the floor so a sheet of plywood and a few 2x4s split down the middle and we now have a shelf.  How do you guys store big sub woofers, they take up too much shelf space.

What do you guys suggest for a cheap way to keep crossover parts organized?     

 

rjj45

The Dynavox 5" honeycomb looks cool, and has a very nice FR, but doesn't look like it has any copper in the gap, so distortion is probably mediocre. Am I right?

rjj45

Kornbread said:

Needed to get some boxes out of the floor so a sheet of plywood and a few 2x4s split down the middle and we now have a shelf.  How do you guys store big sub woofers, they take up too much shelf space.

What do you guys suggest for a cheap way to keep crossover parts organized?     

 

Ideally, lots of medium sized drawers. Other than that, I look for sales on smallish (4 QT, for instance) plastic tubs and label them (IE: CAPS 6-8uF)

Tom_S

Kornbread said:

What do you guys suggest for a cheap way to keep crossover parts organized?     

   

These Plano boxes are good for resistors & smaller coils.



These Harbor Freight boxes work well for bigger inductors and caps. They are cheap too - $5 each!

Tom_S

If you are like many of us, time flies and you'll have a few woofers sitting on the shelf for years. It was told to store them vertically so the cones won't sag over time. I bought some Vifa 5.5" woofers years ago that were sagging badly. The price was great, but it's taken years stored on their backs to return to normal. That reminds me - I should probably check them again.