JBL 308P and 708P

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Azazello
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Re: JBL 308P and 708P

Post by Azazello »

Lego wrote: 2022-02-11 13:52
Azazello wrote: 2022-02-10 14:24 3677 back, now with Tundra 2.2.

They are staying.
any chance of some clips Azazello,please?
I'm not meticulous or fast enough that it would be meaningful. You'd only be listening to differences in installation and time of day. Also moving the 3677 around is an absolute pain. Plus the fact that "bigness" could never be conveyed through a recording.
Last edited by Azazello on 2022-02-13 19:52, edited 1 time in total.
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Re: JBL 308P and 708P

Post by Defender »

thank you Jajo, that was really helpful. It seems you describe the same thing I am wondering about why it is not there even though I dont compare to the 3677 but to my Dynaudio Contour 60.

Musicality with the 308 is simply better but with the Dynaudio I have the feeling the impression does not change when I am in the kitchen or one floor up it sounds as if a band plays in the living room. The sound has authority and a relaxed presentation independent if played real loud or less loud.

With the 308 this feeling goes away as soon as I get away from the couch. And the louder I play the more I hear the 308‘s are under stress (thats probably what you call compressed and distorted).

Thank you for your feedback.
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Re: JBL 308P and 708P

Post by Azazello »

tokenbrit wrote: 2022-02-11 00:42
Azazello wrote: 2022-02-10 14:24 3677 back, now with Tundra 2.2.

They are staying.
Congrats. Is that at the expense of the LSR308s, and are you still waiting on the 708Ps?
Well. I do have a pair on order at the old price. But I don’t think I’ll bother trying them out. I’m to lazy and every time I move the 3677’s I’m scared I’m gonna destroy them (or something else).
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Re: JBL 308P and 708P

Post by jajo »

Azazello wrote: 2022-02-12 21:38
tokenbrit wrote: 2022-02-11 00:42
Azazello wrote: 2022-02-10 14:24 3677 back, now with Tundra 2.2.

They are staying.
Congrats. Is that at the expense of the LSR308s, and are you still waiting on the 708Ps?
Well. I do have a pair on order at the old price. But I don’t think I’ll bother trying them out. I’m to lazy and every time I move the 3677’s I’m scared I’m gonna destroy them (or something else).
Surpirised your order is still alive. I bet their price is up by the same percentage and they would be very happy if you cancelled. Consider keeping the order and sell them to someone who need them :)

In all honesty, keep 3677 since you have the room for them. In the end it is just a speaker. When I say that 708P is better musically, it is still nothing compared to what Källa does.
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Re: JBL 308P and 708P

Post by Azazello »

Defender wrote: 2022-02-11 14:43 yes would be interested to hear clips.
how high above the floor have your JBL308 have been placed?

I dont question the ability of the Tundra Monos together with the 3677 but your setup of the JBLs 308 looked like they are positioned too high.

I tested stands yesterday which are 63,5cm above the floor and it was clearly worse than the other stands which are 60.5cm.
Mainly with respect to voices and with respect to bass performance which seemed like more body but much more unprecise. My room hight is at 4.50Meters if that makes a difference.
I’m sure they could have been much better installed, but it doesn’t matter the least. I know what good installation does and it’s not what I get with 3677. :)
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Re: JBL 308P and 708P

Post by u252agz »

Not strictly on topic - but my JBL305P mark1 arrived yesterday.

Really impressed with them -these are musical speakers and given their size, surprising amount of bass and dynamics.

Has been difficult to source but definitely worth the effort.

Another nod to Jajo for the great recommendation.
Kalla/Sag M/Tun M3/242/LP12/Slip7

Kalla/Giella Pi/JBL308/RS2e

Majik LP12/Boazu/110s
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Re: JBL 308P and 708P

Post by Defender »

I have a question with respect to the ground loop maybe created in case Klimax DS and Akurate DS are used together with Sagatun Monos, LP12 and the JBL 308‘s:
since my main listening is through the LP12 wouldnt it be the better solution to break the ground loop in just lifting the earth on the power cable of the Akurate/Klimax DS instead of lifting it on two JBLs.

Or does that not break the ground loop?
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Re: JBL 308P and 708P

Post by Defender »

now after having optimized everything with the JBL‘s I have to say they are simply the best speakers I owned so far.
There was an issue that they „rocked“ out of the optimal position and I asked myself why are they sounding different after a while until I found out they moved. Clear 2mm thick tape stripes in front of the washers for the spikes helped to keep them where they should be.

… well and my Dynaudio Contour 60 loudspeakers are sold now. They have been really musical and they are still wonderful loudspeakers but overall not as good as the JBL 308‘s.

I am still shaking my head in disbelief.
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Re: JBL 308P and 708P

Post by Fred11 »

Some time ago I cut out some plywood and lied around a couple of jbl 308 mk1s (se picture below). I also made some dust covers. A couple of weeks I finally came across a couple of decent stands, Linn Indeks stands. I really like that they are tripods And can be placed close to back wall. I have two Lejonklou boazu-Jern system and one Källa that is carried up and down between floors, mostly. The Linn stands brought about a really nice change to the Jerns. In the basement system I will now rid myself of a REL sub thanks to the stands.
So now I got a new 308 itch. I carried them out and put them on the Linn stands. I took extra care to tighten the spike-screws on the stands and I also torqued the 308s. It sounded much better with stands. I also have a Kikkin 1.0 with the system.
It plays very musical. The 308s bass is really nice, tight and deep. I do not know if the plywood-hack make them more or less musical. It would be interesting to try some non-wooded ones sometime. But here comes the strange part. I went back to Jern 12ws and Boazu 1.3 which one was the most musical for me…
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Re: JBL 308P and 708P

Post by Fred11 »

Quite strange but the Jern 12WS Boazu sounds more musical in my system. There is a musical flow and naturalness with this combo the 308 Kikkin does not have. I can listen for hours without fatigue and I am just drawn into the music.
I wonder if the 308 would be better with a better pre, like Linn KK or Sagatun?
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Re: JBL 308P and 708P

Post by lejonklou »

Thank you for the report, Fred11!

I don’t find it strange that you prefer Boazu and Jern to Kikkin 1 and JBL 308. Kikkin 1 simply isn’t even close to the preamp in Boazu and I think that determines the outcome, regardless of which is the better speaker.

I recently got a Kikkin 1 back and compared it to my one and only Kikkin 2.2 (which has been powered since it was built in an effort to find out whether the components age and if so, which ones) and the Kikkin 2.2 is so much cleaner and more musical than Kikkin 1. Big difference.

This led me down a path of exploring more recent findings applied to the Kikkin concept. It turns out there’s a lot of potential here and the current Kikkin 3 prototype I think is now one of the best preamps I’ve ever built. I think it’s better than Giella Pi but haven’t compared it to Sagatun Mono’s yet. Considering producing 100 units of this new design, but some components have proven very difficult to source, so we’ll see how it goes.
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Re: JBL 308P and 708P

Post by matthias »

lejonklou wrote: 2022-08-02 20:25 This led me down a path of exploring more recent findings applied to the Kikkin concept. It turns out there’s a lot of potential here and the current Kikkin 3 prototype I think is now one of the best preamps I’ve ever built. I think it’s better than Giella Pi but haven’t compared it to Sagatun Mono’s yet. Considering producing 100 units of this new design, but some components have proven very difficult to source, so we’ll see how it goes.
Thanks for sharing, Fredrik, very interesting!
If I ever replace my preamp I will go for a Kikkin(3 or higher) :-)
Last edited by matthias on 2022-08-04 11:27, edited 2 times in total.
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Re: JBL 308P and 708P

Post by Fred11 »

That is very interesting, Fredrik.
I can here that is loads of potential in the 308 system, but the seamless music now is just better. Kikkin 3.0 sounds very interesting! I would be first on that list if it would be realized and would love to keep testing the 308-plywood further. I actually think the 308 is prettier on the stands than the Jern. Jern on the other hand, especially 12ws with scanspeak elements is really great and especially with LK. Boazu and Jern in small to medium sized rooms is a Scandinavian match made in heaven. Nicklas at Ågrens hifi in Gothenburg introduced me to this combo. We also listened to Kudos X2, a nice speakers also, but the Jern ws was so much more musical and layered. I was shocked at how much the Boazu and Jern could bring out of the music.
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Re: JBL 308P and 708P

Post by Matteo »

lejonklou wrote: 2022-08-02 20:25 Thank you for the report, Fred11!

I don’t find it strange that you prefer Boazu and Jern to Kikkin 1 and JBL 308. Kikkin 1 simply isn’t even close to the preamp in Boazu and I think that determines the outcome, regardless of which is the better speaker.

I recently got a Kikkin 1 back and compared it to my one and only Kikkin 2.2 (which has been powered since it was built in an effort to find out whether the components age and if so, which ones) and the Kikkin 2.2 is so much cleaner and more musical than Kikkin 1. Big difference.

This led me down a path of exploring more recent findings applied to the Kikkin concept. It turns out there’s a lot of potential here and the current Kikkin 3 prototype I think is now one of the best preamps I’ve ever built. I think it’s better than Giella Pi but haven’t compared it to Sagatun Mono’s yet. Considering producing 100 units of this new design, but some components have proven very difficult to source, so we’ll see how it goes.
Interesting

Kikkin 3 could be an ideal solution for by-passing the ADSM/3 DVC.
The problem is that I need 2 inputs (or 1 and a phono board) and a headphones out …

Also the remote control is mandatory.

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Re: JBL 308P and 708P

Post by Spannko »

Fredrick,

Is there any chance that the new pre-amp design will make it into the Boazu?
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Re: JBL 308P and 708P

Post by lejonklou »

If this design makes it to production (essential components missing that are currently scheduled to November 2023 by the manufacturer, but I might be able to find a small batch somewhere), it will not have any headphone output. That simply doesn’t fit the design.

The design is not like Boazu and can’t make it there, for various reasons.
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Re: JBL 308P and 708P

Post by Spannko »

OK, thanks.

Not that the Boazu really needs any major upgrades - from a musical perspective it’s already one of the best amplifiers ever made, if not the very best!
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Re: JBL 308P and 708P

Post by Fred11 »

Fred11 wrote: 2022-08-02 16:21 Some time ago I cut out some plywood and lied around a couple of jbl 308 mk1s (se picture below). I also made some dust covers. A couple of weeks I finally came across a couple of decent stands, Linn Indeks stands. I really like that they are tripods And can be placed close to back wall. I have two Lejonklou boazu-Jern system and one Källa that is carried up and down between floors, mostly. The Linn stands brought about a really nice change to the Jerns. In the basement system I will now rid myself of a REL sub thanks to the stands.
So now I got a new 308 itch. I carried them out and put them on the Linn stands. I took extra care to tighten the spike-screws on the stands and I also torqued the 308s. It sounded much better with stands. I also have a Kikkin 1.0 with the system.
It plays very musical. The 308s bass is really nice, tight and deep. I do not know if the plywood-hack make them more or less musical. It would be interesting to try some non-wooded ones sometime. But here comes the strange part. I went back to Jern 12ws and Boazu 1.3 which one was the most musical for me…
Just read about the invertion in the Kikkin manual. How will this be with with active 308 speakers? Should the signal output from the pre to the speakers be inverted?
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Re: JBL 308P and 708P

Post by lejonklou »

Fred11 wrote: 2022-08-11 20:02 Just read about the invertion in the Kikkin manual. How will this be with with active 308 speakers? Should the signal output from the pre to the speakers be inverted?
In theory, yes they should. I have however had mixed results with this and I'm not sure why.

With Kikkin 1 and 2 and routinely inverted the absolute phase by swapping black and red of the loudspeaker cable in the speaker end. Never questioned it. On an XLR cable hot and cold should be swapped.

With the Kikkin 3 prototype, I did the same after remembering it. Then I was immediately struck by very slight sense of degradation. I tried various tracks just to make sure I hadn't played one that happened to be phase inverted (not sure how common that is these days). Then I changed back. And I think the regular connection is better, although Kikkin inverts the phase. So I've simply left it like that.

It's a very small difference to my ears, but for some reason, I prefer it inverted (=connected normally) with Kikkin 3 proto.
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Re: JBL 308P and 708P

Post by Fred11 »

Sorry for being a bit slow, but switch hot and cold xlr means left output for right speaker and vice versa?
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Re: JBL 308P and 708P

Post by lejonklou »

Fred11 wrote: 2022-08-11 20:27 Sorry for being a bit slow, but switch hot and cold xlr means left output for right speaker and vice versa?
Regards
No, changing absolute phase in an active speaker like JBL308 requires that two conductors inside the XLR connectors on the cable (those that you connect to the back of your speakers) switch places.

There are three conductors in a 3-pin XLR: Hot, Cold and Ground. By swapping Hot and Cold, you invert the absolute phase of the speaker. That means the drive units are pulling in when they normally push out, and pull in when they normally push out.

As music consists of sine waves that make the drive units pull in and push out in long repetitive periods, there is not a big difference between correct absolute phase and inverted absolute phase. I would say that an inverted absolute phase sounds a liiiittle laid back compared to correct absolute phase.
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Re: JBL 308P and 708P

Post by Fred11 »

Oh😊 I see👍
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Re: JBL 308P and 708P

Post by ThomasOK »

Wouldn't swapping Hot and Cold in the XLR cause a problem with the Ground? When I make those cables I bridge the Cold and Ground, as is common. Can you do that if you are connecting the Hot wire to what would usually be the Cold pin? I just don't want anyone to cause problems trying to rewire the XLRs.
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Re: JBL 308P and 708P

Post by Charlie1 »

lejonklou wrote: 2022-08-11 20:14 It's a very small difference to my ears, but for some reason, I prefer it inverted (=connected normally) with Kikkin 3 proto.
That's a surprise. Mind you, the original Kairn improved a lot when I corrected the phase whereas the SMPS one didn't - I think it was that way around anyway - certainly the gap narrowed a lot suggesting that one unit didn't improve much. This is a new step though where it's actually better reversed.

There was something very cool about the Kikkin 1 / 2, helped by its size the price-to-performance ratio. Do you think a v3 can also be as cost effective or is that just not possible nowadays?
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Re: JBL 308P and 708P

Post by lejonklou »

ThomasOK wrote: 2022-08-11 23:48 Wouldn't swapping Hot and Cold in the XLR cause a problem with the Ground? When I make those cables I bridge the Cold and Ground, as is common. Can you do that if you are connecting the Hot wire to what would usually be the Cold pin? I just don't want anyone to cause problems trying to rewire the XLRs.
No. With an RCA to XLR cable, ground (RCA) always goes to ground (XLR).

Then for correct absolute phase, signal (RCA) goes to Hot (XLR) and then Cold (XLR) is tied to ground.

For inverted absolute phase, signal (RCA) goes to Cold (XLR) and then Hot (XLR) is tied to ground.
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