TDL TRL2

[fraser.]

Didnt Elton John have a song about sanding? "Im still sanding, yeah yeah yeah. Im still sanding, yeah yeah yeah......." lol!

oh dear

 

[mikesnowdon]

I found that having just a 5.6uF cap made the treble seem a little ditatched, like it was rolling off too early. I added a 0.39uF bypass and it all sounded better integrated and the lower treble was 'fuller' where it was kind of missing before. Even after this I found the QED actually sounded crap. Its a bright sounding cable designed to make budget systems 'sparkle' a bit up top. You basically have a very high performance speaker now and a good OFC copper cable will probably compliment the speakers much better. Honestly, the DIY cable above is miles better than the QED silver XT in all areas.

Are you listening to fairly modern rock? If so then theres not alot you can do to make it sound good. The problem is in the recording, which is rubbish these days. Classis rock is good if you can get hold of early recordings. This is a really interesting article: "loudness war"

I found this to be the case when I started improving my speakers. I guess one way round it is to pad down the treble a bit when you listen to rock. You can get L-pad attenuators which are little knobs you can turn on the back of the speaker to adjust the level of the tweeter.

 

[fraser.]

I'm very familiar with the compression issue in modern stuff I'm tempted to move onto vinyl to see if i can get better recordings this way but it's such a hassle to buy all the music i love again... It's what i listen to most so might well be worth seeing if it brings an improvement

As a temporary fix i considered using focus rings to see if they help, if i can bring myself to buy anything from russ andrews could be a complete waste of time- i think i'll just get some wee caps and use them as well as you have done.

At the moment i'm using quite nice shielded copper cable from hificollective, can't remember the make but it's cheap and well built at least. Never been into fancy cables- i reckon good connections and good soldering is also key- the cable itself just has to compliment what's in the system already imo- silver anniversary is a no-no then

 

[mikesnowdon]

I quite like the Kings of Leon but its recorded to sound good on radio and argos stereos. The production isnt bad but it just sounds way harsh on my system now. Im thinking of going to 2.2ohm on the tweeters. Unfortunately the better your system gets the more fussy it will be with poor recordings.

I quite like Dire straits. There stuff is supebly recorded as is most 80's stuff I have found.

 

[fraser.]

I can count the number of excellent recordings i have in my collection on one hand lol... maybe i should consider that L pad

I'm happy with how my older stuff sounds; i have everything the Police ever did and some of it sounds incredible; same with most Led Zeppelin, The Clash and even some newer stuff like REM, The Manics etc- It's a shame you have to compromise the system to cater to modern 'tastes'

 

[mikesnowdon]

I'll wait and see what happens with the burn in, if things settle down then that'll be fine, if not then i might try and get hold of some small caps to use with the 5.6s to bring it closer to 6- i'll need your guidance on that though as i haven't tried that before...

Hi Fraser.

So how are they coming along?

If you decide to add a small cap to get closer to the 6uF of the original just bypass the 5.6 as below. As the value is so small you could go for a really nice cap without parting with too much cash. Im thinking of changing the 0.39uF Jantzen for a Mundorf Silver/Oil at some point.

 

[mikesnowdon]

Anyone drawn up a crossover schematic yet?

 

[fraser.]

Mike, my crossover looks different from yours. Have you changed all the caps? I only changed the tweeter cap and resistor and left the main driver untouched- was this stupid? I'll need to take a photo later to show it properly, everything still works but maybe it's not quite right..

 

[mikesnowdon]

I replaced both tweeter and woofer caps and due to their physical size I had to mount them on the other side of the PCB. Same with the tweeter resistor.

I reckon adding the polypropylene cap on the woofer made a nice differece to the upper bass/lower mid. It just sounds more detailed and natural to my ears. Upper bass has a bit more punch too.

I'm sure our crossovers are the same, its just that mine look different with the caps on the other side of the PCB.

Mike.

 

[fraser.]

Ah i see, lol nevermind.

Mine didn't calm down much so i have just added a .22uF mundorf M cap aswell, i'll see what happens...

Cabinets are pretty much sanded as much as i can, i've tried spraying one but i'm not sure if the finish is quite up to scratch- i might have to use a primer first i think

Get some photos up tomorrow

 

[mikesnowdon]

Mine didn't calm down much so I have just added a .22uF mundorf M cap aswell, i'll see what happens...

Hi Fraser.

Can you describe what you mean by that, is it lively treble?

Dont forget you are using different tweeters. I chose the Morels as they were tested by Wilmslow audio against the original Vifa's and were found to work best. I believe they tried many different tweeters including ScanSpeak. Whats the sensitivity of the ScanSpeak units? If its higher than the Morel/Vifa you might want a bigger resistor. If your still having problems getting the HF right give them a call. They should be able to help you. Or get yourself some Morel MDT30s.....

Another thing to try is reversing the polarity on the tweeter. Often crossovers are designed where the tweeter runs out of phase I think. And double triple check all the internal wiring.

 

[mikesnowdon]

Here are some frequency response plots.

Vifa D20TD-05-06 (standard RTL tweeter)

Specs:


Electrical Data
Nominal Impedance Zn 6 ohm
DC Resistance Re 4.2 ohm
TS Parameters
Resonance Frequency fs 1700 Hz
Force Factor Bl 2.2 Tm
Moving Mass Mms 0.2 g
Effective Piston Area sd 4.4 cm^2
Sensitivity 2.83V/1m 89 dB

Morel MDT 30s:

ScanSpeak D2010/8513:

Nominal Impedance Zn 8 ohm
DC Resistance Re 5.7 ohm
Voice Coil Inductance Le 0.07 mH
TS Parameters
Resonance Frequency fs 800 Hz
Force Factor Bl 2.4 Tm
Moving Mass Mms 0.25 g
Effective Piston Area sd 3.8 cm^2
Sensitivity 2.83V/1m 90 dB

 

[fraser.]

Oh dear... the graphs I must confess i've never got my head around the more fancy part of speaker tweaking- can you explain if there's anything in there to suggest any changes? Is the 0.1 sensitivity difference of my tweeter enough to affect the resistance needed? I have a 2R 12W mills on there just now and with the coupled caps it sounds pretty, pretty nice

Interesting about the phase- never thought of inverting it! Someone told me to try facing the speakers right next to eachother facing driver to driver and playing music to check if the phase was correct; have you heard of this? Apparantly the sound should almost disappear

I definitely prefer it with the .22 added though- and i'm very happy with the mundorfs so far. I've got them running right through from my source to the speakers, lovely caps.

 

[mikesnowdon]

(Did I get your Tweeter right? ScanSpeak D2010/8513?)

One thing to consider is the rising FR (see peak at 20K) of the ScanSpeak compared to the more even response of the Morel. The Morel also plays into the lower range much further suggesting a smoother 'cross-over' point perhaps.

To be honest the frequency response of the original Vifa's are really really close to that of the ScanSpeak's indicating that the ScanSpeak should work fine on the RTL2 crossover. Sensitivity is only a tad higher with the ScanSpeaks so they will play slightly louder, you already have a higher value resistor than the original 1.5ohm so no worries there. If your happy with the sound then dont worry about it. You can always try a 2.2 resistor if you find the treble a bit high. May also be worth trying a 0.39uF M-Cap to bring the total capacitance to 5.99uF - much closer to the original value.

I never heard of that check for phase before - interesting. I read in Hi-Fi world (great mag) that there is a little gadget you can buy to test phase. Im fairly certain that most 2-ways have the tweeter out of phase. Have you checked your wiring polarity is the same as before when the speakers were standard?

Are the tweeters flush mounted?

(Try not to get too carried away with fine tweaks, If your happy with it just sit back and enjoy!)

 

[mikesnowdon]

Rumplestilskin.

How are youe RTL's?

Mike.

 

[fraser.]

Yes- you got my tweeter right mate, lovely it is too I think it might sound trebly at lower volumes as the bass doesn't really kick in on my system til it gets to proper volume- and then it's awesome. Today's the first chance i've had to play at high volume since i got my full system up and running:
sources:
Sony CDP M95 with heavy mods to transport- (top loader)
PS1 fully modded
Amps:
AVI S2000 pre
2x AVI S2000 monos

Wonderful sound... all the usual adjectives could be flung around but i won't bother- it's just very very good imo

I'm about to do the final rewiring but not sure which wire to use? I have nice shielded stuff lying around but it's quite thin- much smaller than my speaker cable i'm using just now.. Could i buy some of the stuff you're using Mike?

I've given up trying to carve the perspex for the drivers and have handed that job over to my local carpenter- he said it won't be ready til January so i'll have to put up with the 'DIY' loook for now LOL very nice.
http://i14.photobucket.com/albums/a329/fraser1985/DSCN0737.jpg
http://i14.photobucket.com/albums/a329/fraser1985/DSCN0739.jpg

 

[mikesnowdon]

Looking good.

I would use the same cable you have from amp to speaker....

Mike.

 

[mikesnowdon]

Happy new year TDL modders! (bit late I know)

One of my resolutions is to complete my spekaers with all the planned mods.

Hardwired crossovers, potted in resin.
Enclosures cald in 1/4 birch ply.
New front baffle from 1" birch ply with drivers flush mounted.
Improved internal bracing.
Improved damping of the woofer frame.
New half size grilles.

Look out for updates over the coming months.

Rgds,
Mike.

 

[mikesnowdon]

Fraser,

Have you given up modding your RTL's? Just wondering if you ever got the cabs finnished.

Mike.

 

[fraser.]

Hello! As you might have gathered from another thread in DIY i have a new toy to play with... the TDLs are very nice- but maybe a bit too nice for me. On female vocals and acoustic stuff they blew me away but that only makes up about 5% of my listening... and when i heard those old Sony's i have now they just suited my listening much more, especially now i mainly listen to vinyl; the bass is just much more articulate now, where the TDLs were much smoother and maybe a bit easier to listen to

I still have the cabinets, no doubt i'll go back to them.. probably sooner rather than later