Amplifiers for TAD Exclusive 2402

[enjoy_the_music]

Hi M

Know anyone with a JMF amp? Why oh why did i sell the Berning...your words have come back to haunt me!

Reckon a crown k2 will be good? Also looking for some tube euphonics.

R

I'm delighted to read that they succeeded in the removal of inter leakage Richard. What next I ask?


PS. The JMF/JDF amps are(were) a good match.

[merlin]

Actually on the 2401 the Berning would have been stretched as it doesn't like a 4 ohm load with that output impedence, but yes, for the 2402 there is probably no finer option in my opinion. It would make most of the competition sound broken.

The Crown will give you bass oomph. It's not even remotely in the same class as the Berning for other duties. You could of course try a big class A Accuphase.

[enjoy_the_music]

Yes the 2402's are an easier 8ohm load compared to the 2401's. Checking the db/freq charts they seem to suggest that i need quite a few watts to generate the lower registers...maybe 100+

Also looking at stands for the speakers. Maybe some simple cherry blocks from Yamamoto + some spikes on top and bottom...apparently the bottom of the upper horn must be at eye level.

I have a guy in Stuttgart wanting to check the Twin's out...he already has Rey Audio RM8's.

I also bought rather a nice preamp today...just searching for power now.

Check out the charts attached.

R
ps. whats the story with your babies?

Actually on the 2401 the Berning would have been stretched as it doesn't like a 4 ohm load with that output impedence, but yes, for the 2402 there is probably no finer option in my opinion. It would make most of the competition sound broken.

The Crown will give you bass oomph. It's not even remotely in the same class as the Berning for other duties. You could of course try a big class A Accuphase.

[merlin]

Trust me richard, you don't need hundreds of watts on these - just a decent number of good ones.

Are you speaking with Juergen?

[enjoy_the_music]

Hi M

At the moment i have two pairs of Shindo WE 300b (one pair first generation 1980's and the other from 1991, although i prefer the older!)....and a Shindo preamp (Model 77, simple preamp based on Western Electric circuit).

The 300B's as you know put out only 8W...i don't think thats a problem for light jazz music but something more complex like classical i am worried could cause saturation, although the Shindo's output always belies that power rating...also a 4Watt Yamamoto A-02 i currently have with Yamamoto-San changing the transformers for EU 230V types.

I bought a Wavac PR-T1 preamp also as a keeper, so maybe looking for something to power...hmmm.

Juergen...havent spoken yet but yes i think he may be making a visit.

R

Trust me richard, you don't need hundreds of watts on these - just a decent number of good ones.

Are you speaking with Juergen?

[lfh]

Trust me richard, you don't need hundreds of watts on these - just a decent number of good ones.

I second this. Since you posted all the nice graphs, I did some math for you:

As a first approximation we can assume spherical propagation and free field conditions. The attenuation at distance r compared to the level at reference distance r0 is then given by:

A_dB ~ 10*log10(r^2/r0^2) = 20*log10(r/r0)

Let r0 = 1.0 m =>

A_dB(1.0) = 20*log10(1.0) = 0.0 dB
A_dB(2.0) = 20*log10(2.0) = 6.0 dB
A_dB(2.5) = 20*log10(2.5) = 8.0 dB
A_dB(3.0) = 20*log10(3.0) = 9.5 dB
A_dB(4.0) = 20*log10(4.0) = 12.0 dB

In practice the attenuation will be slightly lower (for reasons outside the scope of today )

Similarily, the level at power P vs that of a reference power P0 is by definition:

L_dB == 10*log10(P/P0)

Let P0 = 1.0 W =>

L_dB(0.01) = 10*log10(0.01) = -20 dB
L_dB(0.1) = 10*log10(0.1) = -10 dB
L_dB(1.0) = 10*log10(1.0) = 0 dB
L_dB(10) = 10*log10(10) = 10 dB
L_dB(30) = 10*log10(30) = 15 dB
L_dB(100) = 10*log10(100) = 20 dB

Finally, assumuing that SPL0 is the sensitivity (SPL at 1 W and 1 m), the SPL can be calculated as:

SPL = SPL0 - A_dB + L_dB

Example:

SPL0 = 95 dB
r = 2.5 m
P = 30 W

=>

SPL = 95 - 8 + 15 = 102 dB

Hence, if you listen at "normal" levels (around 80 dB average in my world), a smallish amp will do. However, do get one with low output impedance. The upside of this will be clear once you switch to active crossovers

HTH
Fredrik

[enjoy_the_music]

Fredrik, brilliant thanks!

In fact i'd been studying this myself after someone, maybe you!, suggested to do so. Yes, its never a perfect world so you always lose something...i suppose the room itself is the attenuator.

From the calculations you gave my Yamamoto 2A3 amp (4W) at full stretch would provide 93db and the Shindo WE 300b (8W) 96db.

My room is what you might call a small/medium sized studio room.

Speakers are installed tomorrow. I havent got any stands for them so i'm going to cut up some spruce beam (10cm x 10cm) for them to sit on in the meantime, just to get them off the floor.

I guess this is just the tip of the iceberg but it gives me a general idea! Thanks so much for taking the time to help.

Richard

Ps. Low output impedance like a Berning OTL...don't rub it in Fredrik, i sold mine recently and Merlin said i'd regret it...now i am! Any suggestions?

[merlin]

Richard,

my take would be that the 1601a isn't going to like seeing some boutique SET with high output impedence trying to drive it - similarly it won't need a Crown K2 to kick it into life. You need a 70wpc - 100wpc SET effectively - now did you really sell that Berning?

[enjoy_the_music]

Yes i did sell it...its somewhere in the land of kookoo clocks and fine chocolate.

I have Jadis JA-200's but i'm taking them to be repaired on friday (hum problems). They are too big to be keepers.

boutique...that's diplomatic.

CAT, Joule, Air Tight and Atma spring to mind. What about ASL Hurricanes?

R

Richard,

my take would be that the 1601a isn't going to like seeing some boutique SET with high output impedence trying to drive it - similarly it won't need a Crown K2 to kick it into life. You need a 70wpc - 100wpc SET effectively - now did you really sell that Berning?

[enjoy_the_music]

And if John Stronczer is using his own Bel Canto gear...why not that.

[enjoy_the_music]

Some photos of my boutique de pede tube amps driving the TAD's...ok for simple music but mushy for anything else.

Actually on the 2401 the Berning would have been stretched as it doesn't like a 4 ohm load with that output impedence, but yes, for the 2402 there is probably no finer option in my opinion. It would make most of the competition sound broken.

The Crown will give you bass oomph. It's not even remotely in the same class as the Berning for other duties. You could of course try a big class A Accuphase.

[dangerisland]

I've owned a pair of 2402s for 4 years. I like the original crossovers and so I use an Audio Research SD135. I'm known for cycling through systems like six packs of beer, but in this case, I've stuck with this setup for over 2 years, basically a millennia. I find myself looking only for source improvements as this system just plays music. NFS.

[Challenger604]

Some photos of my boutique de pede tube amps driving the TAD's...ok for simple music but mushy for anything else.

Attention a ton language s'il te plait!

[speakerdave]

I've owned a pair of 2402s for 4 years. I like the original crossovers and so I use an Audio Research SD135. I'm known for cycling through systems like six packs of beer, but in this case, I've stuck with this setup for over 2 years, basically a millennia. I find myself looking only for source improvements as this system just plays music. NFS.

Sounds like the 2350's didn't do what you wanted. You have a solid set of speakers there. Glad you've found the music again.