JBL LSR305 (1st gen) quasi-anechoic measurements

[Acerun]

Is there a difference between the LSR 305p and the LSR 305p MKII?

 

[sweetchaos]

Here you go:

 

[Acerun]

Thanks. I'm not great at reading these. Do I see smoother and less mid drop on the 305p but a trough at 15k? How would you interpret if you wouldn't mind?

Edit: ok, I see this now. "There is some similarity, though it looks like the newer model might be brighter (but it also has a less pronounced 12k dip and slightly better DI)."

 

[sweetchaos]

Bass extension is the same. Obviously, since it's the same enclosure and woofer size.
The preference score is higher for MKI, due to A) smoothing of the data, since it's just quasi-anechoic response B) the high frequency is more neutral for MKI, where MKII is brighter above 3khz.
The 12khz dip of the MKI was improved on MKII...don't know how much of that is audible.
Early Reflections DI and Sound Power DI look the same.
Power handling should be the same if same enclosure and amplifier.
I think the biggest difference that you'll hear will be the brightness (above 3khz) of MKII, that MKI doesnt have.

I have MKII and I set the dip switch "HF" high frequency to be -2db to bring it back to neutral if I have them playing with a TV.
Otherwise, with a computer, I use PEQ profile to make them more neutral.

 

[Acerun]

Bass extension is the same. Obviously, since it's the same enclosure and woofer size.
The preference score is higher for MKI, due to A) smoothing of the data, since it's just quasi-anechoic response B) the high frequency is more neutral for MKI, where MKII is brighter above 3khz.
The 12khz dip of the MKI was improved on MKII...don't know how much of that is audible.
Early Reflections DI and Sound Power DI look the same.
Power handling should be the same if same enclosure and amplifier.
I think the biggest difference that you'll hear will be the brightness (above 3khz) of MKII, that MKI doesnt have.

I have MKII and I set the dip switch "HF" high frequency to be -2db to bring it back to neutral if I have them playing with a TV.
Otherwise, with a computer, I use PEQ profile to make them more neutral.

Thank you. I have an opportunity to buy either one at a good price, so trying to decide which way to go.

 

[dominikz]

Thank you. I have an opportunity to buy either one at a good price, so trying to decide which way to go.

If you use EQ both look like they can be corrected to a pretty similar overall response (link to comparison tool):

Personally I'd probably go with whichever was cheaper or looks nicer to me (I prefer the look of MK1).
Good luck with your choice!

 

[Acerun]

If you use EQ both look like they can be corrected to a pretty similar overall response (link to comparison tool):
View attachment 169998
Personally I'd probably go with whichever was cheaper or looks nicer to me (I prefer the look of MK1).
Good luck with your choice!

I appreciate your response, I got a pair of MK1 for $189 so I think I should be good.

 

[Acerun]

I appreciate your response, I got a pair of MK1 for $189 so I think I should be good.

If you guys have personal EQ for the MKIs I would love to see it

 

[sweetchaos]

If you guys have personal EQ for the MKIs I would love to see it

Take a look at this.

 

[Acerun]

Okay thanks! This is the one that I am using, was just curious if there were other tweaks or if I should be happy with this. I'm also playing around a little bit.

 

[georgew2]

hello! has any eq for lsr 305 first gen?

 

[DerickHarlin]

Have a look at the answer from sweetchaos two posts above yours.

 

[georgew2]

Have a look at the answer from sweetchaos two posts above yours.

jbl lsr 305 (first gen, 2014 year release) is the MKIs I ?

i though MKIs is newer model.

 

[DerickHarlin]

I have seen the first gen model being referred to as MKI a couple of times here which makes sense to me since the release of the second gen (MKII) saying „JBL LSR 305“ can cause confusion.

 

[dominikz]

jbl lsr 305 (first gen, 2014 year release) is the MKIs I ?

i though MKIs is newer model.

JBL LSR305 (matte front, measured in this thread) is the older generation (MkI).
JBL 305p MkII (gloss front, measured here and here) is the newer generation.

 

[Weeb Labs]

I captured a quick measurement of my own first generation LSR 305 and the result matches that of @dominikz very closely. It appears to be waveguide cancellation.

 

[dominikz]

I captured a quick measurement of my own first generation LSR 305 and the result matches that of @dominikz very closely. It appears to be waveguide cancellation.

View attachment 188716

Thanks for posting!
Interestingly your measurement doesn't seem to show the 2-10kHz downward tilt that I saw in mine:

Interesting thing is that I get a better match between units with the tweeters switched:

May I ask at what distance you measured from and did you use tweeter axis?
Mine was taken on tweeter axis from 50cm distance - though if I were to do it again I'd probably measure at ~90cm (3 x speaker height) to have more certainty that measurement is out of loudspeaker nearfield). Thanks!

 

[Weeb Labs]

Thanks for posting!
Interestingly your measurement doesn't seem to show the 2-10kHz downward tilt that I saw in mine:

I wouldn't read too much into it beyond the 11KHz cancellation. It was sitting between my monitors at the time.

 

[Weeb Labs]

Oops. I missed the second half of your post. My measurement was captured at about 200mm from the tweeter axis but I had also tried various other distances ranging from 50mm to 600mm. Beyond 80mm, the results were effectively identical (ignoring increased reflection shmoo with distance).

 

[dominikz]

Oops. I missed the second half of your post. My measurement was captured at about 200mm from the tweeter axis but I had also tried various other distances ranging from 50mm to 600mm. Beyond 80mm, the results were effectively identical (ignoring increased reflection shmoo with distance).

Thanks! While the tweeter driver response itself shouldn't change much beyond about 75mm (~1" x 3), the cabinet diffraction and waveguide effect may persist for quite a bit further away. A practical rule of thumb is that a safe distance to measure should be about 3x the largest dimension of the loudspeaker (usually height).

E.g. I had to measure the 5,25" Genius SP-HF3000A at least at ~1m to stabilize the HF response and 6,5" Revel M16 at ~75cm. On the other hand the 5" Neumann KH120 measured HF response stabilized around 50cm distance already.

With the JBL LSR305 measured response stabilized at about 50cm (I checked on-axis measurement at 30cm, 50cm and 80cm before doing the spin).