DIY progress report

The one and only
Joined 2001
Paid Member
Bricolo said:
Mr Pass, about the XVR1
is the "gain changing with order" thing avoidable?

Yes. The XVR1 maintains the same gain for 6/12 slopes and then
has a different figure when you go 18/24. There would be
no reason why the gain couldn't be customized to unity, but I
have not chosen to do that. The change can be slight or great
depending on how you set the Q, and of course there is a
volume control at the output of each filter set.
 
Nelson Pass said:
About the crossover, I dropped the
project

Can we read this as that there will not be a Pass active crossover for a number of digits ?

Oops, i flunked an entire tube of LT1028's some time ago anticipating a superior solution.
The easiest for my 8 Aleph babies now would be Jens's board, but that means acquiring train loads of opamps again.

Time to think: shall i shoot myself or not ?
:clown:
 
The one and only
Joined 2001
Paid Member
As far as I can make out, Jen's filter circuit offers the
equivalent of the project I had, and you need only
insert either op amps or the circuit in the XVR1 owner's
manual. For filled in gain stage values, look at the MOX
thread.

My preference is not for op amps, largely because they need
to be run close to unity gain, and I find the stability marginal.

You can create filters using just unity gain followers, but you
won't get as much flexibility on Q values.
 
Nelson, I guess that these days you are busy playing with Fostex FE 166 ES-R...

However it would be nice to know if and when we could expect an article on ZEN V8?

That would be a transconductance ZEN, right?

In the meantime, have you tried the FE 166 ES-R in the Kleinhorn?

Enjoy...
 
donzi

It is a little one.
 

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jleaman said:
My new speakers Running off a pair of gain clone's till my other amps get here : O)

Do you find hiding the ugly *** speakers in a pandimonium of chaos somehow distracts the eye from the fact that the speakers are still nude?? :)

Maybe you think that veneer will color the sound? Come on Dude dress your speakers!!

BTW. How do they sound?

Regards

Anthony
 
They Sound awesome. I Love em. there 2.5 way speakers. a cap on the tweeter a coil on the bottom driver and the middle one is full range. They need new binding post's on the back so i can bi-amp them with a amp per each speaker so 6 channel's with a active x-over i'm thinking about using my pen-zen's a i have 4 boars just need to get them here also and finnish them but also to build chassis for my aleph and see how they sound also. I'm thinking about some ideas for a finnish. It's hard because i want it done right the first time and want to be happy with what i choose. Id like to change a few things put a base on them and change the internal stuffing and wire to some nice hi grade stuff.

Any way chris did a fantastic job im happy that i was able to buy them.

Here is a shot of the top..
 

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Mr. Pass,

I read your second installment of the Kleinhorn saga with great enjoyment. More proof that the journey is more fun than arriving at the destination.

I have looked forward to this article because of the promised use of the current amp with a ribbon tweeter. You did not disappoint. I have a couple of things I'm curious about.

1) What is the sonic difference and measured difference between running the tweeter with a current amp vs, a voltage amp like the A3. Did you try both?

2) Why did you use an active crossover on the tweeter rather than a passive current source filter on the output of the amp. A two pole would have given you a cap in series with the driver and kept any DC offset out of the transformer.

3) Is Fig.7 the entire network that exists between the current amp and the driver? If it is then it must include the bandpass filter, the impedance smoothing network and the driver EQ function. When I read the article on current source crossovers I wondered how the driver impedance/EQ components would be integrated with any crossover components. Fig. 7 and the supporting text (I make joke) seem to suggest that this is seriously empirical territory.

By the way, any plans to put the 166ES-R into the hot seat in the KH's?


Thank you again.

Graeme
 
The one and only
Joined 2001
Paid Member
gl said:
1) What is the sonic difference and measured difference between running the tweeter with a current amp vs, a voltage amp like the A3. Did you try both?

2) Why did you use an active crossover on the tweeter rather than a passive current source filter on the output of the amp. A two pole would have given you a cap in series with the driver and kept any DC offset out of the transformer.

3) Is Fig.7 the entire network that exists between the current amp and the driver? If it is then it must include the bandpass filter, the impedance smoothing network and the driver EQ function. When I read the article on current source crossovers I wondered how the driver impedance/EQ components would be integrated with any crossover components. Fig. 7 and the supporting text (I make joke) seem to suggest that this is seriously empirical territory.

4) By the way, any plans to put the 166ES-R into the hot seat in the KH's?

1) I have listened to both, and I prefer the F1 slightly over an
Aleph 30. The tweeter has a flat impedance and doesn't
particularly care (the response curve looked the same) but I
attribute the difference to the lack of feedback.

2) I failed to mention that I placed a bundle of parallel Zen
capacitors in series with the tweeter. The filter it imposes is
500 Hz.

3) Fig 7 is the loading of the F1 into the DX4. In addition, there
is a single pole on the top and bottom before the amplifier as
mentioned in the text.

4) Actually this weekend I'm planning the TAD 1201's and
4001's with the Emlar horns.

:cool: