Anybody using a passive pre with your Lampi

Tomy2Tone · « **on:** 30 Jun 2016, 03:26 pm »

Just looking to see what people's experiences are using a Lampi dac with a passive preamp. I tried a passive last year with a different dac and it was ok but never felt it was as dynamically engaging as the tubed active I was using so I'm going to try a passive again but with my L4.

For any L4 owners, any idea what the output voltage is? Does it vary with what type of tubes are use? Definitely seems there are quite a few variations in tubes being implemented in the L4 series.

doak · « **Reply #1 on:** 30 Jun 2016, 04:40 pm »

Using a DIYHIFI Django TVC with my L4G5, output tubes are pr. 6DL8 & pr. 12AU7.
Works beautifully. Volume control nearly never gets past half way.

Tomy2Tone · « **Reply #2 on:** 30 Jun 2016, 07:18 pm »

Quote from: doak on 30 Jun 2016, 04:40 pm

Using a DIYHIFI Django TVC with my L4G5, output tubes are pr. 6DL8 & pr. 12AU7.
Works beautifully. Volume control nearly never gets past half way.

Thanks Doak

I'll be trying a Hattor passive here in a few weeks. It'll be the second component in my system that will be directly from Poland...

http://www.hattor.com/

DaveC113 · « **Reply #3 on:** 30 Jun 2016, 09:02 pm »

Looks interesting... I use the Amtrans carbon film resistors they use in their high end passive pre model in my tube amps/preamps, with Mills in the power supply. They are pricey though!

Tomy2Tone · « **Reply #4 on:** 30 Jun 2016, 09:49 pm »

Quote from: DaveC113 on 30 Jun 2016, 09:02 pm

Looks interesting... I use the Amtrans carbon film resistors they use in their high end passive pre model in my tube amps/preamps, with Mills in the power supply. They are pricey though!

I opted for the takman rey's. According to Arek Kallas, maker of the pre, the constant input impedance allows any source/dac to be compatible and he just recently added an optional buffer to allow for any length of cables and impedance match any amp. Hoping for the best here...

Folsom · « **Reply #5 on:** 30 Jun 2016, 10:47 pm »

The output impedance is 600ohm so it's a more compatible DAC with passive pre's than some other Lampi's.

That said I think having to turn two knobs is hell on earth.

Tomy2Tone · « **Reply #6 on:** 1 Jul 2016, 11:56 am »

Quote from: Folsom on 30 Jun 2016, 10:47 pm

That said I think having to turn two knobs is hell on earth.

I guess you've never played "tune in Tokyo"

It's got a remote for volume, the two knobs are more like balance controls

mresseguie · « **Reply #7 on:** 1 Jul 2016, 03:12 pm »

Quote from: Tomy2Tone on 1 Jul 2016, 11:56 am

I guess you've never played "tune in Tokyo"

It's got a remote for volume, the two knobs are more like balance controls

I didn't know about 'Tune in Tokyo', but I am guilty of something similar. I used to say "ICRT, Taiwan" while 'dialing'. I guess you had to be there.

Tomy2Tone · « **Reply #8 on:** 1 Jul 2016, 04:41 pm »

Quote from: mresseguie on 1 Jul 2016, 03:12 pm

I didn't know about 'Tune in Tokyo', but I am guilty of something similar. I used to say "ICRT, Taiwan" while 'dialing'. I guess you had to be there.

Glad to see somebody gets my humor, never know on this site.

Have you been up to see Dave yet in CO to hear his passive?

Folsom · « **Reply #9 on:** 1 Jul 2016, 06:09 pm »

So does that mean it uses digital/relay control for actual volume, and the stepped attenuators are just for balancing?

poseidonsvoice · « **Reply #10 on:** 1 Jul 2016, 09:01 pm »

Quote from: Folsom on 1 Jul 2016, 06:09 pm

So does that mean it uses digital/relay control for actual volume, and the stepped attenuators are just for balancing?

I think perhaps the relays switch from one attenuation level to the next attenuation level [as I don't see a motor], similar to a TAPX, except that the actual component performing the attenuation here is a resistor not an autoformer or transformer. So the quality of the resistor becomes UBER important but tweak able, which is why he has choices of AMRG, Vishay SMD, Takman, etc...depending on budget. But dual motors would do the same job! Perhaps I should email him n the actual mechanism...

His prices are actually very nice for what he is trying to offer from a "looks" standpoint, but there is competition from Tortuga, TAP-X, Django, etc...lots of choices for us audio geeks which is great. I hope Tomy2Tone will chime in on the sonics soon.

The basic component is a Khozmo attenuator in this unit.

Balance "control" is provided by changing the attenuation levels relative to Left and Right channels. So if the level on the right is 42 and the level in the left is 40, your center will move to the side that is louder or less attenuated.

Best,
Anand.

Folsom · « **Reply #11 on:** 1 Jul 2016, 09:18 pm »

I find balancing is a rare need. It usually means you didn't measure from the walls behind the speakers, and measured from the walls in front of them. That's my finding, unless there's something wrong. But I've never been in a super unbalanced shaped room either.

Please do ask him. I don't see motors... it make me believe those are not the full volume mechanism. Here's what a remote version looks like using them.

His prices are very low for using those attenuators for any purpose at all.

Tomy2Tone · « **Reply #12 on:** 1 Jul 2016, 10:22 pm »

It'll be a couple weeks or so before I receive the Hattor but will definitely chime back in with my impressions on how it works with my L4 and amps. I'll post pics with the top off as well. From my understanding, all the pics you see on the Hattor site is with preamps that come with remote. Arek Kallas, the designer, said he is discontinuing the Khozmo Acoustic site and is going to only offer the 64 step attenuator version with remote on the Hattor site.

As far as I know volume can be controlled by either the front of the amp or by remote. And thats either mono or stereo volume. What the mechanism is for volume I have no idea.

I've read and heard from two owners who prefer the Hattor to their previous preamps. One was a Gammut D3i which retails for $8K and a forum member here who said the Hattor sounded better in his system than a Audio Research Ref5se which I believe retails for $12K. So it shouldn't sound too bad, at least in my system I hope...

doak · « **Reply #13 on:** 1 Jul 2016, 10:56 pm »

Quote from: DaveC113 on 30 Jun 2016, 09:02 pm

Looks interesting... I use the Amtrans carbon film resistors they use in their high end passive pre model in my tube amps/preamps, with Mills in the power supply. They are pricey though!

Gorgeous unit. Hope you love it.
Built my first resistive passive 30 yrs ago and have been using TVC/AVC types for 15.
Level of success is system dependent - source output level/impedance, amp input sensitivity, speaker efficiency - but when everything is synergistic, IMO, there's no beating it with an active device with gain .... or, doing so WILL cost a BUNDLE of bucks.

poseidonsvoice · « **Reply #14 on:** 2 Jul 2016, 01:55 am »

Quote from: Tomy2Tone on 1 Jul 2016, 10:22 pm

It'll be a couple weeks or so before I receive the Hattor but will definitely chime back in with my impressions on how it works with my L4 and amps. I'll post pics with the top off as well. From my understanding, all the pics you see on the Hattor site is with preamps that come with remote. Arek Kallas, the designer, said he is discontinuing the Khozmo Acoustic site and is going to only offer the 64 step attenuator version with remote on the Hattor site.

As far as I know volume can be controlled by either the front of the amp or by remote. And thats either mono or stereo volume. What the mechanism is for volume I have no idea.

I've read and heard from two owners who prefer the Hattor to their previous preamps. One was a Gammut D3i which retails for $8K and a forum member here who said the Hattor sounded better in his system than a Audio Research Ref5se which I believe retails for $12K. So it shouldn't sound too bad, at least in my system I hope...

Actually, I don't think it will sound bad at all from a transparency and detail standpoint...only you will be able to tell us if it has enough "oomph and drive."

Quote from: Folsom on 1 Jul 2016, 09:18 pm

I find balancing is a rare need. It usually means you didn't measure from the walls behind the speakers, and measured from the walls in front of them. That's my finding, unless there's something wrong. But I've never been in a super unbalanced shaped room either.

I agree. In addition, many recordings do not have the singer "dead center." In fact, I find that very cool in my system. More real & accurate.

Best,
Anand.

Tomy2Tone · « **Reply #15 on:** 2 Jul 2016, 02:01 am »

This little Tisbury passive showed up today from ups and if it's any indication of the possibility for the Hattor I think I'll be a happy camper. The dial is between 12 and 1 and its pretty loud on certain tracks. For $200 shipped this a nice little piece! The dial does jump quite a bit in reference to volume so the 64 step on the Hattor should be quite nice.

poseidonsvoice · « **Reply #16 on:** 2 Jul 2016, 02:14 am »

Nice! On the low end of the price scale there is also Luminous Audio Axiom - https://luminousaudio.com/collections/axiom-ii-passive-preamp

The ones with the "Walker" mod uses the Khozmo stepped attenuator unit

Best,
Anand.

poseidonsvoice · « **Reply #17 on:** 3 Jul 2016, 02:35 am »

Folsom,

Thanks to Tomy2Tone, he has confirmed that the mechanism of attenuation is indeed through switching of relays as I initially suspected.

Best,
Anand.

rajacat · « **Reply #18 on:** 3 Jul 2016, 02:56 am »

It's odd that nobody has mentioned Audio Circles own Tortuga Audio.

I built up one of the boards, it works perfectly and the sound quality/transparency is superb. http://www.tortugaaudio.com/

glynnw · « **Reply #19 on:** 3 Jul 2016, 02:58 am »

+1 sold my TVC immediately after hearing the Tortuga