Multicore/dsp and latency. (setup options)

[lagoausente]

Hello everybody.
First this is my setup:
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Scope Professional plus: balanced analog (XLR), AES/EBU (XLR), 2 × ADAT
Laptop Thinkpad T40 with magma 2 slot. (pcmcia-pci adapter)
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In the other hand I bought some months ago a IBM thinkpad T400, that has a Core Duo 2.5Ghz processor, 3gb of RAM. Has expresscard and pcmcia.Have to say that the T400 pcmcia is very slow, performs much worse that my old T40 so is not usable.
I bought it thinking on getting the Xite-1 in the future but I´m considering have an hybrid dsp/native with the actual Scope/Pro.
The reason is that I reallly don´t use much synths but miss a more modern sampler. Also considering use convolution for amp simulation or guitar rig. Also, maybe the Kit BFD for drums. Issue to solve is latency.
Actual processors seem to be very quick, but I have no desktop to can test the Scope Pro with a modern cpu. In the other hand the thinkpad T400 Core Duo 2.5ghz seems very quick, but coulcdn´t test it yet with a decent soundcard.


Options:

Option 1- Buy this expresscard/PCI adapter http://www.virtuavia.eu/shop/expresscar ... 29858.html
Have read the thread about it , it will work ok with one card, and have to model the case to adapt to the card length, this is no problem.
Questions here are:
a) If I use any sampler or VST as stand-alone, probably I could play with less latency that using them inside Cubase. If I play through Cubase and low too much the buffer will have risk of drops. (That´s what I experience on the past with desktop 1.6 athlon processor).
b) Posible solution could be using VDAT, start stand-alone with Asio with low buffer and record it through VDAT.

Option 2- Buy a desktop Cpu+ a soundcard with 2xADAT. Use is for stand-alone apps with low latency, and send the outputs through ADAT to the T40+Scope Pro that shoud be running Cubase+Scope.
a) Disvantage of this, more space, less portable, and the T400 should be without use.

Option 3- Like before but buying the expresscard/pci adapter for the T400 instead of the desktop. Maybe no much sense since for the adapter price and something more should get a more powerfull desktop maybe.

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Well, I should like to know your opinions, maybe many of you know the performance of actual cpu better than me and could tell me what should be the best way to do it.
What I want is to can add Native option with a low latency but with no drops, should I need two pcs? or not?
Any opinion should be apreciated.
Thanks a lot.

[Sounddesigner]

The newer computers will allow for low latency with the Sampler type apps you want to use. Alot can be ran at 1.5ms buffer-size long as you avoide the plugins with very large latencies. If your only going to use a few samplers with a small amount of effects you might even get away with 32-samples buffer-size with some soundcards coupled with a powerful computer. At 44khz Samplerate SCOPE allows for as low as 1.5ms Asio/Wave buffer-size (5.9ms Roundtrip) and a fast modern computer can do alot at that buffer-size long as your not using extreme-latency-inducing plugins. The more carefull you are at that buffer-size the more you'll be able to load.

If i where you and i did not need XITE-1 and portability then i would get a desktop computer for the SCOPE Professional card you have cause i don't trust magma's too much. A Intel i7 950 processor is only about $299 in USA and it can do alot at low latency plus give enough power to last many years if your needs are'nt too great. IMO the SCOPE Pro with i7 is the better option.


EDITED

[at0m]

Have to say that the T400 pcmcia is very slow

I think your T40 has the better PCMCIA chipset (Ti?) and the T400 hasn't, and that's not going to improve by hanging anything expensive (Xite, PCI chassis with Scope) on it. So a USB ADAT card (or maybe the T400 has firewire?) could work on that machine, but wouldn't dare to invest on PCMCIA low-latency DSP stuff for the T400.

If you have the space (driving by car to gigs? or are you taking public transport?), a little desktop machine would beat the T400 and even T40's PCI hands down - for latency and stability. Let alone the price difference between desktops and laptops and their expansion options.

Just a couple thoughts...

[lagoausente]

The newer computers will allow for low latency with the Sampler type apps you want to use. Alot can be ran at 1.5ms buffer-size long as you avoide the plugins with very large latencies. If your only going to use a few samplers with a small amount of effects you might even get away with 32-samples buffer-size with some soundcards coupled with a powerful computer. At 44khz Samplerate SCOPE allows for as low as 1.5ms Asio/Wave buffer-size (5.9ms Roundtrip) and a fast modern computer can do alot at that buffer-size long as your not using extreme-latency-inducing plugins. The more carefull you are at that buffer-size the more you'll be able to load.

If i where you and i did not need XITE-1 and portability then i would get a desktop computer for the SCOPE Professional card you have cause i don't trust magma's too much. A Intel i7 950 processor is only about $299 in USA and it can do alot at low latency plus give enough power to last many years if your needs are'nt too great. IMO the SCOPE Pro with i7 is the better option.


EDITED

Portability is something I like a lot, not for gigs but I prefer much more a laptop if posible.
I prefer directly record the audio from the sampler, so I´m really not have lot of plugins at time when playing, just use as a hardware instrument, take it´s audio output and record it to an audio track.
I have tested my T400 with the onboard souncard and the Asio4all driver. I can play with 120 sample buffer, even I suspect real latency may be a bit more, maybe the soundcard is using a harware hidden buffer.
I guess how should perform a soundcard like this one: http://www.thomann.de/es/terrasoniq_phase_x64_usb.htm
Is USB 2.0 souncard, that means 60MB/s I think, while PCI is 133Mb/s, does this something to do with the latency?

[lagoausente]

I think your T40 has the better PCMCIA chipset (Ti?) and the T400 hasn't, and that's not going to improve by hanging anything expensive (Xite, PCI chassis with Scope) on it. So a USB ADAT card (or maybe the T400 has firewire?) could work on that machine, but wouldn't dare to invest on PCMCIA low-latency DSP stuff for the T400.

If you have the space (driving by car to gigs? or are you taking public transport?), a little desktop machine would beat the T400 and even T40's PCI hands down - for latency and stability. Let alone the price difference between desktops and laptops and their expansion options.

Just a couple thoughts...

T400 has both pcmcia and expresscard. Pcmcia has Ricoh chipsed what is quite bad. But till I know Expresscard is a direct connetion to the pci bus without any chipset controller. In fact, I can´t see the expresscard device on the device manager as a separate device so it should work ok with Xite-1. The problem of Xite-1 is it´s price, and I really don´t use so much power. Rarely use synths, and still haven´t music that justify mixing with Pro plugins.
Regarding magmas and pci bandwith there is something extrange. On the Masterverb thread I saw guys with mondern computers having pci-overflow message with 4-5 masterverbs, while I can load 7-8 on my old T40 and the magma. So that means that regarding the pci-overflow on Scope there are some things goind wrong with some systems.
Note that I can load more masterverbs on my old T40 setting the cpu speed of the centrino at lower 0.6 ghz, while if set to max 1.5ghz I have much more problems with pci-overflow.
I really don´t know if there is any relation with the Asio latency.
T400 has firewire, but I don´t like it much, even there was some info on RME web about hidden buffering on firewire soundcards. I had one of them on the past, and really the Asio buffer was not very reliable as latency indicato (there is some hidden latency on firewire itself).

Have anyone experience about the 2.0 soundcards?
The desktop option as a compact unit is not bad (unless the pci-overflow message). Have you any suggestion of a compact PC that could load the long Pro card?

[Bud Weiser]

Is USB 2.0 souncard, that means 60MB/s I think, while PCI is 133Mb/s, does this something to do with the latency?

60MB thruput w/ USB 2.0 is a theoretical value for both directions, In and Out.

Real world thruput w/ USB 2.0 is not more than 26MB each direction.

All depends on quality of the controller in addition.

Bud

[Bud Weiser]

T400 has firewire, but I don´t like it much, even there was some info on RME web about hidden buffering on firewire soundcards. I had one of them on the past, and really the Asio buffer was not very reliable as latency indicato (there is some hidden latency on firewire itself).

To get most out of Firewire,- you need Texas Instruments (TI) firewire chipsets in each device, the computer/laptop AND the ext. audio/midi interface.
In opposite to USB 2.0, theoretical data thruput w/ Firewire is 64 MB, but in EACH direction,- so it´s always faster than USB 2.0.
RME Fireface 800 and Fireface 400 are reference interfaces of the industry and yes, there is hidden buffering, but it´s only a few samples.
Fireface 800 and 400 are fast and reliable.

You don´t need a Fiewire 800 card to run these interfaces as long you don´t plan to cascade several interfaces or to use the interface and a Firewire drive at the same port.

If you look for a USB 2.0 interface,- RME Fireface UC and Babyface are the recommendations of experienced pro DAW builders,- the only recommendations.
You´ll get performance close to the Firewire interfaces of RME (w/ a machine matching the tech specs and which is well configurated).

Bud

[garyb]

as long as no one is paying for the session, fw is fine. for serious or any professional work, it's stupid.

[lagoausente]

Firewire on my T400 has Ricoh chipset, what is know by low performance.

I undecided if try the Exsys expansion box, or building a compact desktop. The compact desktop I don´t like that should need to work all the time with a remote desktop tool like radmin, what seems not very grateful.
Regarding Cpu performance I have a doubt, hope someone can solve it. My T400 has this processor: P8700 2.53 GHz Centrino 2 VPro (3M L2 Cache, 1066 MHz FSB, 64 bits.

Regarding the actual 4 cores actual desktop machines, will affect the mininum buffer and so the latency? Or should be limited by other parameters like the Exsys adapter? (in if the case).
Question is if there is no much inprovemente in ms of latency, the desktop option should be much more anoying.
I know that if I run effects than it should be diferent, but I guess using just a sampler if the cpu is something the will establish the diference on the buffer settings..?

[garyb]

there are other advantages to desktop archetecture than just possible latency or chipset issues, like extra harddrives, better power supplies and many other little things that make the difference between dicey and solid.

fw will always be a poor choice compared to pci or pci-e. fw is several layers above the os, while pci or pci-e is at the motherboard level, below the os. fw is way yoo flakey for mission critical work, though it's more than a little bit covienient and plenty usable when used for causual purposes.

[lagoausente]

Well, I tried Virtuavia Expresscard-PCi adapter, the ATX version that has not power limit and finally couldn´t get midi work and STS samplers don´t sound.
I don´t know if the problem comes from the adapter or my laptop, but I decided to return it.
So I´m going now for a desktop option.
I had bought one of this: http://www.pc.ibm.com/de/lenovo/pressep ... ternal.jpg
Have disambling the floppy and cd-rom. It comes with a double pci riser card. I tested the Virtuavia ATX on that box using an aditional extended pci cable.
The cpu is a celeron 2.6ghz, and I´m thinking about upgrade it for a new multi-core CPU, to get the lowest latency and no drops.
Do you think that is too small case? I think that If manage ok the space an ad some nice fans I think should be ok.
I should like you to recomend me the CPU. You mentioned the I3. Really does it worth the price? I mean, the lastest technology price usually is not proportional to the performance improvement, for example, a CPU of 120, should perform half the I3 if cost 240? I guess no. So I should like you to suggest the best performance/price ratio I can get now. Or do you still recomend the I3 all over the others?

The newer computers will allow for low latency with the Sampler type apps you want to use. Alot can be ran at 1.5ms buffer-size long as you avoide the plugins with very large latencies. If your only going to use a few samplers with a small amount of effects you might even get away with 32-samples buffer-size with some soundcards coupled with a powerful computer. At 44khz Samplerate SCOPE allows for as low as 1.5ms Asio/Wave buffer-size (5.9ms Roundtrip) and a fast modern computer can do alot at that buffer-size long as your not using extreme-latency-inducing plugins. The more carefull you are at that buffer-size the more you'll be able to load.
EDITED

mmm, how can you do that on Scope? Using Asio4all? Asio4all use the waveplayrec driver, mmm, is this one a 24 bit driver??
If I use Scope ULLI settings the min settin is 3ms, what must be 132 samples...so are your speaking about other sound cards?
I still have the doubt if use only one PC for Scope and for Native samplers, or if use two pcs. One with Scope and recording audio, and one only as a sampler. That should mean buy another soundcard for the desktop (sampler) with two adat outputs, and then send them to the Scope pc (what could be the old laptop with the magma).
If I use only one PC, it should be all in one, Scope in the new mobo+cpu, that should need to perform ok at very low latency as sampler and recorder at the same time.
I should use multiple output sampler like druming BFD, that´s why I should need two adat, to can record individual audio tracks for mixing ok the drums.
I forget the midi track recording for the issues discussed on the other thread on this forum.

[Sounddesigner]

I think the i7 950 has the best price/performance ratio out of all Intel cpus. The i7 950 costs $299 and runs at a speed of 3.06GHZ. The i7 950 has 8 virtual-cores wich is alot of extra performance if your host supports hyperthreading/multiple-cores properly. I7 950 is on intels high-end socket LGA 1366 and every i7 on this socket has greater memory-bandwidth then the other intel processors on different sockets so i7 950 can load more samples at low latency then the other processors on different sockets (such as i5 and i3's). The i7 950 use to be $599 but the price was lowered to $299 and it is very worth it imo. It has advantages over the other intel processors on different sockets (8 virtual-cores, more memory bandwidth, upgradable to 6-core/12-virtual-core westmere on same socket). If you cannot afford the i7 950 then get the fastest i3 you can. Here is a link to a benchmark of intel and AMD processors - http://www.adkproaudio.com/benchmarks.cfm


SCOPEs ULLI will allow for latency as low as 3ms at 44khz samplerate BUT this is NOT the total Roundtrip latency. There is additional Asio i/o latency of 1.5ms input and 1.5ms output combined with the ULLI latency for a total of roughly 6ms Roundtrip latency (Sonar reads mines as 5.9ms Roundtrip). If Asio buffer-size is set to 1.5ms input latency then all soundcards will have atleast a Roundtrip latency of 4.5ms or more and with many it's more then that.

I don't know if that Case you chose is big enough or not., hopefully someone else here can help you with that question.


PS. Keep in mind that Sonic Core is about to release new SCOPE Hardware that's smaller and cheaper then XITE.

EDITED

[lagoausente]

I think the i7 950 has the best price/performance ratio out of all Intel cpus. The i7 950 costs $299 and runs at a speed of 3.06GHZ. The i7 950 has 8 virtual-cores wich is alot of extra performance if your host supports hyperthreading/multiple-cores properly. I7 950 is on intels high-end socket LGA 1366 and every i7 on this socket has greater memory-bandwidth then the other intel processors on different sockets so i7 950 can load more samples at low latency then the other processors on different sockets (such as i5 and i3's). The i7 950 use to be $599 but the price was lowered to $299 and it is very worth it imo. It has advantages over the other intel processors on different sockets (8 virtual-cores, more memory bandwidth, upgradable to 6-core/12-virtual-core westmere on same socket). If you cannot afford the i7 950 then get the fastest i3 you can. Here is a link to a benchmark of intel and AMD processors - http://www.adkproaudio.com/benchmarks.cfm


SCOPEs ULLI will allow for latency as low as 3ms at 44khz samplerate BUT this is NOT the total Roundtrip latency. There is additional Asio i/o latency of 1.5ms input and 1.5ms output combined with the ULLI latency for a total of roughly 6ms Roundtrip latency (Sonar reads mines as 5.9ms Roundtrip). If Asio buffer-size is set to 1.5ms input latency then all soundcards will have atleast a Roundtrip latency of 4.5ms or more and with many it's more then that.

I don't know if that Case you chose is big enough or not., hopefully someone else here can help you with that question.


PS. Keep in mind that Sonic Core is about to release new SCOPE Hardware that's smaller and cheaper then XITE.

EDITED

mmm, so you were talking about 3ms ULLI, I thought you told 1.5 ms total. I think I could play Guitar Rig setting my laptop T400 Intel Core 2 Duo to max performance at 3ms without drops (no aditional, no recording tracks etc).
Do you think that playing 10 or 15 audio tracks should force me to increase the buffer?
Very good link the benchmarks test. Thanks a lot.
Regarding the new hardware smaller and cheaper the Xite...., I should be very interested since I already have preamps..., AD, etc.

[Sounddesigner]

Playing back 10 or 15 tracks should not cause your buffer-size to increase on the more recent computers, i don't know about your T400 Intel Core 2 Duo tho.