Looking for 6 inch subwoofer

[news.rcn.com[_2_]]

Sorry if this question has been asked a million times before but I lost
track of car audio components a few years ago and it does defy googling
somewhat.

I have a space for two 6 inch speakers in the rear doors of my car and want
to put a subwoofer into it. The front has space for a passable mid range
unit of about the same size.

Has anyone developed anything with any sort of extended bass which can fit
into this space yet? I know it is TOO SMALL but was wondering if anyone had
developed any technology which could do this? Such as a long-throw cone??

[GregS[_3_]]

In article >, "news.rcn.com" > wrote:
>Sorry if this question has been asked a million times before but I lost
>track of car audio components a few years ago and it does defy googling
>somewhat.
>
>I have a space for two 6 inch speakers in the rear doors of my car and want
>to put a subwoofer into it. The front has space for a passable mid range
>unit of about the same size.
>
>Has anyone developed anything with any sort of extended bass which can fit
>into this space yet? I know it is TOO SMALL but was wondering if anyone had
>developed any technology which could do this? Such as a long-throw cone??

If you use a closed box woofer, one with a fairly high Q, you can put it into a small
box. Being too small, it will have a peak in the upper bass range. This peak can be
fairly small though. It depends on the driver and box size. The actual diameter of
the driver will be 6.5 inches. Thats whats available. you can equalize that bass to any
low frequency you want. The trade off will be efficiency, power handling, and excursion
limits. In one car I have 4 -6.5 inchers in a closed hidden box under a compartment,
otherwise the system is stealth. Putting drivers in doors can be complex. You need a solid
foundation and adequate damping material. It will make the door heavy. You need
to plug driver parameters and box sizes into a program to see whats up.
There is no new technology. I had the Bose 901 II with 9 -4.5 inch drivers in a small
box, with a low frequency -3 db of 30 Hz. It was boosted +18 dB at 30 Hz.

greg

[Frank[_8_]]

> There is no new technology. I had the Bose 901 II with 9 -4.5 inch drivers
> in a small
> box, with a low frequency -3 db of 30 Hz. It was boosted +18 dB at 30 Hz.

The original 901 required a huge amount of power and it was new technology
and concept when it came out. There wasn't too many amps in its day that
could drive it loud. On the other hand, back in the 60s, there was
Electro-Voice 30" woofer that required very power to drive it, and when
coupled to the right box, it could blow a match out about five feet in front
of it.

[Matt Ion]

Frank wrote:
>> There is no new technology. I had the Bose 901 II with 9 -4.5 inch drivers
>> in a small
>> box, with a low frequency -3 db of 30 Hz. It was boosted +18 dB at 30 Hz.
>
> The original 901 required a huge amount of power and it was new technology
> and concept when it came out. There wasn't too many amps in its day that
> could drive it loud. On the other hand, back in the 60s, there was
> Electro-Voice 30" woofer that required very power to drive it, and when
> coupled to the right box, it could blow a match out about five feet in front
> of it.

There's really no substitute for a good horn-loaded sub design, when it
comes to raw earth-shaking power... unfortunately the horn needed for
sub-bass tends to be a little big for most cars :)

Pity the Servo-Drive design never caught on for cars...

[Arny Krueger]

" Frank" > wrote in message

>> There is no new technology. I had the Bose 901 II with 9
>> -4.5 inch drivers in a small
>> box, with a low frequency -3 db of 30 Hz. It was boosted
>> +18 dB at 30 Hz.
>
> The original 901 required a huge amount of power and it
> was new technology and concept when it came out.

High price of trying to get bass out of a small box.

> There
> wasn't too many amps in its day that could drive it loud.

Tubes. Ugh.

> On the other hand, back in the 60s, there was
> Electro-Voice 30" woofer that required very power to
> drive it,

Its voice coil could handle only about 60 watts. It only had a few mm of
Xmax. A modern 10' subwoofer driver could probably out-displace it.

> and when coupled to the right box, it could
> blow a match out about five feet in front of it.

Nope.

[Frank[_8_]]

"Arny Krueger" > wrote in message
. ..
>" Frank" > wrote in message
>
>>> There is no new technology. I had the Bose 901 II with 9
>>> -4.5 inch drivers in a small
>>> box, with a low frequency -3 db of 30 Hz. It was boosted
>>> +18 dB at 30 Hz.
>>
>> The original 901 required a huge amount of power and it
>> was new technology and concept when it came out.
>
> High price of trying to get bass out of a small box.
>
>> There
>> wasn't too many amps in its day that could drive it loud.
>
> Tubes. Ugh.
>

By the 1960s we had both tubes and transistors. The transistor than was
very mature as it was invented in 1947 and much of the physic were been
worked out years ago. Nothing wrong with tubes, many high systems end still
use it but neither tubes nor solid state could drive the 901 at very high
pressure levels.

>> On the other hand, back in the 60s, there was
>> Electro-Voice 30" woofer that required very power to
>> drive it,
>
> Its voice coil could handle only about 60 watts. It only had a few mm of
> Xmax. A modern 10' subwoofer driver could probably out-displace it.
>

It doesn't have to handle many watts as it was very efficient. I have not
seen a 10" sub (not a 10') that could out pump a 30" as the excursion has be
9x times more.


>> and when coupled to the right box, it could
>> blow a match out about five feet in front of it.
>
> Nope.
>

Why did you say nope? The box I was referring to was designed by a UC
Berkeley physicists back in the mid 1960. It was a corner exponentially
folded horn and was based on a famous horn design except he corrected all
the folding angles. A few people I talked to said it did blow out the match,
including a chief engineer - no reason for them to lie for they were not
connected with the project. It was for his personal use, not commercial.
Believe what you believe.

[Arny Krueger]

" Frank" > wrote in message


> By the 1960s we had both tubes and transistors.

True for many applications, but not for others.

> The
> transistor than was very mature as it was invented in
> 1947 and much of the physic were been worked out years
> ago.

Depends which end of the 60s, you're talking. In 1960 there were no
competitive mainstream solid state power amps, receivers or integrated amps.
By the end of the 60s, there were, but power ratings above 200 wpc were
still in the next generation.

The first stereo amp reviewed by Stereo Review was the Knight kit KG-870, in
1965. It was not competively reliable. The first stereo amp reviewed by
High Fidelity was the Knight KN400, in 1961. It had low power and was not
competively reliable. By 1966 some SS gear with adequate power and
reliability crept onto the market. Really high-powered SS amps waited until
1973 or later.

> Nothing wrong with tubes, many high systems end
> still use it

More for effect, than good sound at a reasonable cost.

>but neither tubes nor solid state could
> drive the 901 at very high pressure levels.

For what reason?

r hand, back in the 60s, there was
>>> Electro-Voice 30" woofer that required very power to
>>> drive it,

>> Its voice coil could handle only about 60 watts. It only
>> had a few mm of Xmax. A modern 10' subwoofer driver
>> could probably out-displace it.

> It doesn't have to handle many watts as it was very
> efficient.

It was not that hard to fry. I know people who have done it without abusing
it.

>I have not seen a 10" sub (not a 10') that
> could out pump a 30" as the excursion has be 9x times
> more.

The 30W had only a few mm Xmax, maybe two or three. PIcking the higher
number, it would take a 10" woofer with 27 mm Xmax to duplicate it. Those
are pretty rare. Being a little more practical, there are popular 18"
woofers with 27 mm Xmax. Derating that to 30 inches puts us at about 7 mm
Xmax, which the 30W most definately can't do.










t he corrected all the
> folding angles. A few people I talked to said it did blow
> out the match, including a chief engineer - no reason for
> them to lie for they were not connected with the project.
> It was for his personal use, not commercial. Believe what
> you believe.

[GregS[_3_]]

In article >, "Arny Krueger" > wrote:
>" Frank" > wrote in message

>
>> By the 1960s we had both tubes and transistors.
>
>True for many applications, but not for others.
>
>> The
>> transistor than was very mature as it was invented in
>> 1947 and much of the physic were been worked out years
>> ago.
>
>Depends which end of the 60s, you're talking. In 1960 there were no
>competitive mainstream solid state power amps, receivers or integrated amps.
>By the end of the 60s, there were, but power ratings above 200 wpc were
>still in the next generation.
>
>The first stereo amp reviewed by Stereo Review was the Knight kit KG-870, in
>1965. It was not competively reliable. The first stereo amp reviewed by
>High Fidelity was the Knight KN400, in 1961. It had low power and was not
>competively reliable. By 1966 some SS gear with adequate power and
>reliability crept onto the market. Really high-powered SS amps waited until
>1973 or later.

I just pulled out my 61 catalog. I must have built a SS amp sometime later.
It was a smaller amp with germanium transistors and transformer interstage
driver. It had that great clear SS sound.

Doesn't look like they used the KG- etc in 61 year. They just said 40 watt amp or
something like that.

greg

[Arny Krueger]

"GregS" > wrote in message

> In article
> >, "Arny
> Krueger" > wrote:
>> " Frank" > wrote in message
>>
>>
>>> By the 1960s we had both tubes and transistors.
>>
>> True for many applications, but not for others.
>>
>>> The
>>> transistor than was very mature as it was invented in
>>> 1947 and much of the physic were been worked out years
>>> ago.
>>
>> Depends which end of the 60s, you're talking. In 1960
>> there were no competitive mainstream solid state power
>> amps, receivers or integrated amps. By the end of the
>> 60s, there were, but power ratings above 200 wpc were
>> still in the next generation.
>>
>> The first stereo amp reviewed by Stereo Review was the
>> Knight kit KG-870, in 1965. It was not competively
>> reliable. The first stereo amp reviewed by High
>> Fidelity was the Knight KN400, in 1961. It had low power
>> and was not competively reliable. By 1966 some SS gear
>> with adequate power and reliability crept onto the
>> market. Really high-powered SS amps waited until 1973 or
>> later.

> I just pulled out my 61 catalog. I must have built a SS
> amp sometime later.

> It was a smaller amp with germanium transistors and
> transformer interstage
> driver. It had that great clear SS sound.

Sounds like the same RCA Transistor Manual amp schematic that also graced
the Heath AA-22 which I owned for a while. I sold it and went back to Dyna
tubed amps after I fried the second set of output transistors.

The transistors were as I recall 2N2147 germanium transistors. Plenty fast,
good beta, but only 25 watts dissipation and wildly insufficient SOA.

The first commercial SS amps with reasonable power and reliability used
silicon outputs (2N3055) in the much-maligned but actually really pretty
good "Quasi Complementary" design. The secret of their reliability were some
SOA limiters that were based on a few cheap parts including a couple of
$0.35 small signal transistors.

> Doesn't look like they used the KG- etc in 61 year. They
> just said 40 watt amp or something like that.

There was another Heath SS amp, the AA 21 I think, that used the same output
devices, 4 per channel, in what they called the "totem pole" configuration.

Totem poles came back in the silicon era in amps like the Dyna 400, which
used 8 devices per channel. But now we're talking 1974-1975.