Turtlerock Forum

Latest waste of time: building my own monitors. I'm using Joe Malone's amp PCB, so I've posted the build over at his site rather than here, but you can visit the thread at http://jlmaudio.com/forum/viewtopic.php?p=230.

This will sit at the end of my "small dial" box.

Chris,

Where are these amps/pcbs listed on JLM's site............

ChrisO

Yo Ausrock Chris

The amp PCBs not yet up for general sale: they're mentioned in the JLM forum which includes all the beta kits.

To indicate pricing, per channel the amp kit was $55, the driver was $264, the MDF box was $66 and I probably spent about $100 on other bits and pieces (of which $40 was the 1.5mH inductor - I bought a high quality one). So all up its about $1000 for the pair, which is comparable to the cost of entry level monitors. The benefit is that I am getting MUCH better than entry level sound.

Ahha........thanks mate.

I'm needing a different amp to power my nearfields and a pair of these may be ideal, the DIY monitors themselves could be something for the future.

ChrisO

Rob Squire should chime in here - he's go a stereo amp made up from these PCBs for sale, which might be what you're looking for.

chiming in.....

yep, Broadcast has put together a stereo 25watt version. Joe and I jointly developed these amp modules. The original motivation was for me to put a power amp together to suit smaller nearfields, out of this came the DIY module from JLM. The thing we really nailed was providing a true balanced input, without adding additional circuitry. Whilst the amp is very simple the performance is quite outstanding.
see the Broadcast "ready to go version" at http://www.broadcastproaudio.com/new.htm
Mixmasters is bundling the amp with it's pyramid speakers ( the new auratone )

Rob

I'll probably wait until I finish rebuilding/waterproofing the inside of the studio and see if the kits are available from JLM as I need more than the 25watts.

For those not on the JLM forum, here's SN 0001

good for you chris
and is the end result worth the effort ....?
do they sound like a keeper ....?

Thanks Rick

They sound pretty much like I wanted them to sound. They are not particularly loud, but are very listenable, and are definately a step on from my current choices of monitoring (JBL control 1s with subwoofer and Mordant Short bookshelfs) in terms of accuracy and (having just finished building the stereo pair) soundstaging. So yes, they are keepers for the moment.

But having said that, my ears are still on a journey of exploration and learning. I suspect in after a few years of listening I'll start to hear the shortcomings more than I'm hearing the improvements, and then it may be time to move on.

They look great!

How do you find the highs and lows on the Jordan drivers compared to the standard 2-way offerings? Are you going to use them with a sub?

Im super interested because I like the idea of no crossover etc. Id considered doing a 2-way with the JXR6 as a tweet with a 10" on the bottom too.

Peter

Good Morning Peter

I need to qualify my comments with the observation that the Jordan's need about 14 days' use to get fully burnt in, and I'm not there yet.

I have no probs with the highs at all. Ed Jordan really has devoted his later life to getting the highs right in his full range drivers (you'd know that the JXR6 goes way over 30kHz before hitting -3db).

With the bass, the design cutoff in the 8L format is around 56Hz from memory. You still get some signal below that, of course, its just attenuated by more than 3db. That's the "on paper" answer. In practice, with any musical note you get harmonics, and these harmonics reproduced on the JX92s give a surprisingly good illusion of the missing frequencies. Its like your mind filling in the end of the sentences. You don't miss it as much as you'd think.

I have a sub from my old JBL Control1 system which I can use if required, but its nowhere near the quality of the Jordans. At the moment, I'm willing to just go with the 92's without the sub for most work (I've just finished mixing a lovely 7-track flute/piano combo for a DVD and I didn't miss a sub at all). I'll pull out the sub if I get a client with doof music, but that would be about the only need.

I'm liking these just a little bit more each day.

You know that Jordan has an Oz distributer up in Qld? I found him very knowledgeable and helpful with any questions. I was considering building the JXR6 line array but he said that you'd definitely need a sub for monitoring duties there, whereas the 92's had just enough bottom end.

The crossoverless design is an interesting experiment for me, and these are really the first time I've listened to a quality full range driver. The design compared to the standard 2 driver offering is a trade off, sacrificing volume and bottom end for better accuracy and soundstaging, and so the real question is whether that sacrifice is a good one or not for the music you have to deal with. I'd still like a pair of BAM1s for the fuller range option, but in the mean time these will do me just fine.

I've been nosing around the full range offerings from Fostex although if I'm honest with myself, it's going to be quite some time before I'm in a position to actually do anything about them. There's other priorities both in life and in the studio to be taken care of first.

ChrisO

thanks Chris,

Its good to know that the highs are there with the 4" jordan - I may reconsider and try a pair of the jx92s instead.

I mainly do rock stuff so the Jordans may not be the right design for me - but I think crossed with a seas/peerless/vifa 8" or 10" woofer (per side) in the 100-200Hz range they might just do the trick.

The jxr6 would have to be crossed higher to handle rock at a decent volume -I reckon 300-400Hz but per pair they are cheaper so possibly a better idea for a 2-way....

would be interested to hear your impressions when you've spent some more time with them...

Ausrock... I've looked at those fostex full rangers as well - I get worried about breaking them hehe - very limited xmax - although really sensitive so may not be a problem. If I was into jazz/classical I reckon they would be great.

I know what you mean about other things taking your time..........if living didn't cost me money.......I wouldn't work.......

Peter