Here's some findings from a kit builder...James, you're welcome to pop-in and add to it...Thanks!
"Played some tracks "Daves True Story" for balance, DiMeola, McLaughlin, etc (Sat Night ...) for detail, Olatunji "Babatunde" for Bass, Red Priest version of Vivaldi "4 seasons - track 1 - Spring" for the speaker resonance check and natural instrument sound, Enya "Amarantine" for resolution on multitrack overdubb (difficult for the old phillips 1541A dac players), Mahler Symphony No 2 (Budapest Orchestra with Ivan Fischer) [ I'm not a big classic person and especially Mahler but this selection stayed the whole 27 minutes!]
Suffered thru that ghastly Alison Krauss "Forget About It" AudioPhool remastered crap (maybe okay on MP3 players, or something!!) and just changed to Peggy Lee "Fever" - rather good recording from some years ago....
Added an Elna 1000uF/25V cap across the battery and improvement in clarity but initially unbalanced the sound a lot, with lack of bass but after about 30 minutes now, the balance has come back and the improved clarity extends to the bass as well - I'll leave the cap there for a week and then try it without, to check if it's just my imagination or not - has happened before a few times!
[After dinner change, not the week! - just out of curiosity, replaced the 1000uF Silmic with a 4700uF Elna for Audio (Starget) cap and more bass at the start - how interesting ....]
Now, in comparison to the sound of the PassLabs X2.5 preamp, the sound is considerably cleaned, more open, more detailed and without any of the usual fatigue that normally accompanies this - the only problem is the lack of gain on some of the quieter tracks so I'll just increase the CD o/p to about 3volts that should take care of things.
Looks like the poor old Pass X2.5 is in need of the external shunt reg power supplies, plus a heart transplant! - the difference is pretty obvious.
Playing music at low levels doesn't seem to "thin the sound down" as you have found, and I can confirm that the same thing is apparent here as well.
I wonder if I can get this same "sound" of your Warpspeed (W/S) from the Cavalli valve buffer (Heretical III) for the "gain stages" of the electronic Xover - I do need the buffers between the filter stages and can fit the W/S to the Xover main vol control - hmmm ...
Perhaps the most noticeable difference to the Passlabs preamp is heard on my AKG k170 headphones via Patrick's (EUVL) DAO follower amp - I use this as my reference and the sound of the F3 amp, the Coral beta8 Full Rangers (150Hz+) & Lorrantz 12" bass drivers (150Hz-) are setup to approach this sort of sound - a bit of a cross between monitors and hifi speakers, in my reasonable acoustic room, a bit bass shy.
So, you have designed and built a winner here, no doubt about it - I'll get my Uriah's built up kit back next weekend and see what differences there is between them."
"Played some tracks "Daves True Story" for balance, DiMeola, McLaughlin, etc (Sat Night ...) for detail, Olatunji "Babatunde" for Bass, Red Priest version of Vivaldi "4 seasons - track 1 - Spring" for the speaker resonance check and natural instrument sound, Enya "Amarantine" for resolution on multitrack overdubb (difficult for the old phillips 1541A dac players), Mahler Symphony No 2 (Budapest Orchestra with Ivan Fischer) [ I'm not a big classic person and especially Mahler but this selection stayed the whole 27 minutes!]
Suffered thru that ghastly Alison Krauss "Forget About It" AudioPhool remastered crap (maybe okay on MP3 players, or something!!) and just changed to Peggy Lee "Fever" - rather good recording from some years ago....
Added an Elna 1000uF/25V cap across the battery and improvement in clarity but initially unbalanced the sound a lot, with lack of bass but after about 30 minutes now, the balance has come back and the improved clarity extends to the bass as well - I'll leave the cap there for a week and then try it without, to check if it's just my imagination or not - has happened before a few times!
[After dinner change, not the week! - just out of curiosity, replaced the 1000uF Silmic with a 4700uF Elna for Audio (Starget) cap and more bass at the start - how interesting ....]
Now, in comparison to the sound of the PassLabs X2.5 preamp, the sound is considerably cleaned, more open, more detailed and without any of the usual fatigue that normally accompanies this - the only problem is the lack of gain on some of the quieter tracks so I'll just increase the CD o/p to about 3volts that should take care of things.
Looks like the poor old Pass X2.5 is in need of the external shunt reg power supplies, plus a heart transplant! - the difference is pretty obvious.
Playing music at low levels doesn't seem to "thin the sound down" as you have found, and I can confirm that the same thing is apparent here as well.
I wonder if I can get this same "sound" of your Warpspeed (W/S) from the Cavalli valve buffer (Heretical III) for the "gain stages" of the electronic Xover - I do need the buffers between the filter stages and can fit the W/S to the Xover main vol control - hmmm ...
Perhaps the most noticeable difference to the Passlabs preamp is heard on my AKG k170 headphones via Patrick's (EUVL) DAO follower amp - I use this as my reference and the sound of the F3 amp, the Coral beta8 Full Rangers (150Hz+) & Lorrantz 12" bass drivers (150Hz-) are setup to approach this sort of sound - a bit of a cross between monitors and hifi speakers, in my reasonable acoustic room, a bit bass shy.
So, you have designed and built a winner here, no doubt about it - I'll get my Uriah's built up kit back next weekend and see what differences there is between them."
Other notes from James...
"It'll be interesting to see what happens as I get used to it - annoying the others a bit this late at night with the much higher volume that it seems available without seeming to be LOUD - and I do like that bass clarity - even "Buddha's Party's" now listenable!
...and will plod on to finish the F5 amps and get started with the Xover - I got a few extra pcbs for the symetrical B1 to use for that B1 Xover but, after the contrast of the W/Speed to the X2.5 preamp that uses similar buffers, not so sure now and will have a bit of a rethink..."
"It'll be interesting to see what happens as I get used to it - annoying the others a bit this late at night with the much higher volume that it seems available without seeming to be LOUD - and I do like that bass clarity - even "Buddha's Party's" now listenable!
...and will plod on to finish the F5 amps and get started with the Xover - I got a few extra pcbs for the symetrical B1 to use for that B1 Xover but, after the contrast of the W/Speed to the X2.5 preamp that uses similar buffers, not so sure now and will have a bit of a rethink..."
I don't want to give the impression that the PassLabs X2.5 Preamp is a low quality product - it's not, in any system - it does function better as a balanced preamp and does everything you can expect from an item from PassLabs, even this the entry model.
I've had it for a couple years now and it's been mated up to quite a few different amps/sources and never a mis-match - quite surprising, really.
Allan's "Warpspeed" is a Passive Vol Control and a rather well designed item indeed - it has remarkable clarity and detail and suits the F3 perfectly, not an easy thing to do - even Uriah's variable LighterNote design needed the buffer.
I'm playing with the capacitors across the Leds now, and battery supply variations later - it'll be interesting .....
I've had it for a couple years now and it's been mated up to quite a few different amps/sources and never a mis-match - quite surprising, really.
Allan's "Warpspeed" is a Passive Vol Control and a rather well designed item indeed - it has remarkable clarity and detail and suits the F3 perfectly, not an easy thing to do - even Uriah's variable LighterNote design needed the buffer.
I'm playing with the capacitors across the Leds now, and battery supply variations later - it'll be interesting .....
I appreciate you chiming in, James. No doubt that cleared up the air for us Pass fans. I'm just happy getting it compared to a quality product and able to hold its own.
Is it then safe to add another advantage over other LDR designs -on the Warpspeed's ability to nicely partner with low input impedance amps without the need for a buffer? The F3 being about 9k?
I've held back on declaring it outright until someone actually says so with actual use. I was shooting for this advantage during the design process. Theoretically it will probably work down to a low 4k of amp input impedance and probably paired with 3Vpk or more of Source voltage output...so DACs with this higher than standard output will really help.
"Straight, No Chaser!" I think will be a nice signature...
Is it then safe to add another advantage over other LDR designs -on the Warpspeed's ability to nicely partner with low input impedance amps without the need for a buffer? The F3 being about 9k?
I've held back on declaring it outright until someone actually says so with actual use. I was shooting for this advantage during the design process. Theoretically it will probably work down to a low 4k of amp input impedance and probably paired with 3Vpk or more of Source voltage output...so DACs with this higher than standard output will really help.
"Straight, No Chaser!" I think will be a nice signature...
Just a bookmark...
Related discussions going on here...http://www.diyaudio.com/forums/anal...uator-new-passive-preamp-411.html#post2574068
Related discussions going on here...http://www.diyaudio.com/forums/anal...uator-new-passive-preamp-411.html#post2574068
Have Warpspeed, Will Travel…
Over the weekend I gutted my earlier diy version of the Lightspeed, re-used its box and wired up a Warpspeed. I built this with the hope of letting it loose for DIYAudio members who would like to give it a listen in the comfort of their couch’s sweet spot. It’s open to members residing in the lower 48 states of the USA.
The idea is to ship it to the first member who expresses interest, with the agreement to have it to hopefully enjoy for 10 days and then ship it to the next member on the list. And it goes on as long as the list grows. I’ll cover the initial USPS Insured Priority Mail Medium Flat Rate Box shipping cost with Delivery Confirmation for tracking. Please keep this as our shipping standard (Total of $14.50 including $200 Insurance).
The picture shows the unit with 4x in-parallel 9V battery supply which I will include. Please replace when the voltage measures <5.0V or as needed. This Warpspeed is stereo Unbalanced with the middle RCA connectors as L/R INPUTs; the outer RCAs are OUTPUTs; it has a power switch to conserve battery power; and a DC power INPUT connector.
I take it as a given that the unit will be treated with love and care
as it goes thru every stop of its 2011 US concert tour. I’ll ship it once we hit 5 members.
For interested parties the list starts now and here...
Over the weekend I gutted my earlier diy version of the Lightspeed, re-used its box and wired up a Warpspeed. I built this with the hope of letting it loose for DIYAudio members who would like to give it a listen in the comfort of their couch’s sweet spot. It’s open to members residing in the lower 48 states of the USA.
The idea is to ship it to the first member who expresses interest, with the agreement to have it to hopefully enjoy for 10 days and then ship it to the next member on the list. And it goes on as long as the list grows. I’ll cover the initial USPS Insured Priority Mail Medium Flat Rate Box shipping cost with Delivery Confirmation for tracking. Please keep this as our shipping standard (Total of $14.50 including $200 Insurance).
The picture shows the unit with 4x in-parallel 9V battery supply which I will include. Please replace when the voltage measures <5.0V or as needed. This Warpspeed is stereo Unbalanced with the middle RCA connectors as L/R INPUTs; the outer RCAs are OUTPUTs; it has a power switch to conserve battery power; and a DC power INPUT connector.
I take it as a given that the unit will be treated with love and care
as it goes thru every stop of its 2011 US concert tour. I’ll ship it once we hit 5 members. For interested parties the list starts now and here...
Attachments
On sunday mornings I have been listing to "G Strings" on WPFW 89.3 (they sream on the web) a great jazz program that centers on jazz guitar fo many years. It is a time to just listen, not fooling around with speaker placement, switching cables,or equipment. So it was with great anticipation that I would be listening to the Warpspeed for a second time, sort of a reality check from the fist listen a couple of days ago. Would I be disapointed and have to put my preamp back in line.
The program comes on at 9am so I turn every thing on a 8:30 to stablize go back and finish cleaning up after breakfast. At 8:55 I set the SqueezeBox touch to Internet radio and select WPFW and slowly turn up the volume. There it was the cleanest, purist sound I have ever heard over the internet. Dead quite background, so much bass I had to turn down the subs, and the sweetest mids and highs I have ever heard from my maggys. Still blown away...........
thanks for putting out a gamechanger
The program comes on at 9am so I turn every thing on a 8:30 to stablize go back and finish cleaning up after breakfast. At 8:55 I set the SqueezeBox touch to Internet radio and select WPFW and slowly turn up the volume. There it was the cleanest, purist sound I have ever heard over the internet. Dead quite background, so much bass I had to turn down the subs, and the sweetest mids and highs I have ever heard from my maggys. Still blown away...........
thanks for putting out a gamechanger
Blues - I'm in the Bay Area and will most likely make it Burning Amp. I've been there every year so far, so it would be unusual for me not to go. I already own one of your Warpspeed modules, which I've built into a very simple package. I can take my version if you think that would show things off in the right way.
I've attached a snapshot of mine for your reference - you've already gotten this via personal email a few months back.
---Gary
Attachments
Thank you for your offer, Gary. Please bring it only if it won't get in the way of your itinerary, and if you are still enthusiastic about its sound quality after living with it for some time now.
I will try to have the Traveling @Warpspeed unit available too if someone in the area is interested...
I will try to have the Traveling @Warpspeed unit available too if someone in the area is interested...
Update on the Traveling @Warpspeed
The demo unit is now with nicksgem10s in MI...here's a quote from his email:
"I have had a couple of good listening sessions and was able to sit and enjoy some music.
I am beyond impressed with what I am hearing. It has so much resolution and I have had zero listener fatigue. This is not an easy feat to accomplish. You should be very happy. It sounds free from coloration.
It is going to end up in my main reference system. There is no question. I would really like a couple more days to enjoy it but I will ship it to the next person when you tell me it is time.
I have really made up my mind."
Thanks Nick!
The demo unit is now with nicksgem10s in MI...here's a quote from his email:
"I have had a couple of good listening sessions and was able to sit and enjoy some music.
I am beyond impressed with what I am hearing. It has so much resolution and I have had zero listener fatigue. This is not an easy feat to accomplish. You should be very happy. It sounds free from coloration.
It is going to end up in my main reference system. There is no question. I would really like a couple more days to enjoy it but I will ship it to the next person when you tell me it is time.
I have really made up my mind."
Thanks Nick!
