Tripath bi-amp suggestions?

[soren5]

Hello,

I'm looking to bi-amp my Linn Katan speakers using a miniDSP and one or two Tripath based amps. The small 2-way Katans have 8Ω woofers (5") and 6Ω tweeters and the speakers have a 85dB sensitivity. I'll be using them in a small room about 10m2.

My preamp/DAC is a Beresford TC-7520.

I don't have great soldering skills so I'd prefer to get something that's already assembled. What would you recommend me to buy? So far, I've looked at the following options:

1. 41Hz Amp9-BASIC assembled, 4x25W 8Ω, 75 EUR excl. shipping.
   This is an easy solution, but I'm wondering if the amp is powerful enough for my setup, even considering the small room.
   
   
2. Sure 4-channel TK2050 D-class Audio, 4x30W 8Ω, app 21 EUR excl. shipping.
   Another easy and VERY cheap solution, but I'm not sure about the quality of this amp. Any comments on this?
   
   
3. 2x HifimeDiy T1, 2x100W 8Ω, app 72 EUR excl. shipping.
   I hear a lot of good things about these amps, but would it be slightly overkill in my setup?

I'd like to hear if any of you has experience with Tripath bi-amping, either with the above mentioned amps or with something else?

Thanks!

[soren5]

No comments??

I've tried to do some calculations on the power requirements for my speakers, but I'm not sure how it works if I choose to bi-amp.

I'm currently driving the speakers (passive crossover) with a SS amp with 2x60W RMS in 8Ω and this seems to be powerful enough in my room. The 41Hz Amp9-Basic has 4x25W in 8Ω so a total of 100W - just 20W less compared to my current setup. Does this mean that the Amp9 would be sufficiently powerful, or am I doing the calculation wrong?

OTOH two HifimeDiy T1s are the same price as an Amp9, but I guess the power supply requirements would be a somewhat different matter and therefore much more expensive...

Which way would you go? Or do you have some other recommendations on bi-amping class-d amps?

Thanks for giving some imputs. I'm really no expert, that's why I ask you

[goosewing]

Its always nice to help someone else spend their money

Out of your choices I would suggest the pair of Hifimediy T1 amps plus a pair of the smps300r power supplies they handily also supply now. Or even their T4 amps if your budget allows. Nice things are sid here about the T1 and T4, also the L20D amplifier which I would suggest is worth considering as a third alternative. Any of these should do the job very well.

The AMP4 will obviously play music in your system and if you like quiet acoustic stuff will probably do fine, but really it is an amp suited to more efficient speakers. I assume from your intention to use miniDSP your budget is not so limited that you are forced to choose the Sure on cost grounds.

[kristleifur]

I have some experience with TK2050 amps, namely 41Hz Amp4 and Amp11. The stuff in the thread about the Sure implementation seems very strange - chips getting hot, which simply indicates a shoddy implementation. I'm not interested in trying one myself.

Hifimediy seem to make quite fine amps. Haven't tried though.

However, note that the Amp9-BASIC is 4*25W if you power it with 12V. If you power it with around 24V, which it can easily take, it's 4*50W at least. Probably more. -- EDIT -- no wait, that's not true ... it's less into 8 Ohm. Sorry

(However, I'd like to add that any good Tripath amp has great dynamics and effortless sound throughout the full power range, so it sounds like a way more powerful traditional amp. I guess it has something to do with the good current handling afforded by the high efficiency.)

[soren5]

Thanks a lot for your inputs!

Regarding the AMP9, it seems that the actual max output using 28V DC and 8Ω drivers is 4x20W with around 0.01% THD+N - see last paragrah in this link:

41Hz Audio - AMP9 measurements

So it'll probably be a little too weak for my setup and I think I'd be better off wit a pair of T1s. Now, is it possible to use one big SMPS (e.g. the SMPS500R) for both amps and then put them into one enclosure?

@goosewing: You're suggesting higher watt amps such as the T4 and the L20D, which both more than exceeds my power requirements. Is the general rule that the more watts in class-d the better the sound? And although I wouldn't utilise the extra power of such amps, would I still gain something from choosing e.g. the T4 or L20D over the T1?

[goosewing]

@goosewing: You're suggesting higher watt amps such as the T4 and the L20D, which both more than exceeds my power requirements. Is the general rule that the more watts in class-d the better the sound? And although I wouldn't utilise the extra power of such amps, would I still gain something from choosing e.g. the T4 or L20D over the T1?

I wouldn't presume to give a definitive answer here but no I don't think there is a correlation between power and sound quality and a small high quality T amp in the right environment and paired with the right speakers should be able to give the larger amps a run for their money.

So why have I been suggesting the higher powered amps? Three things really, your speakers aren't very efficient, buying higher power T amps doesn't incur the same financial penalty as going up in power with class A or AB amps does and lastly there seems to be opinions that clipping is not particularly nice in T amps. i.e. if you have a good 10W class A tube amp it may still sound good even if it is driven in to clipping. This means it can delivery an average power output of 5W (which would give very decent sound levels with moderately efficient speakers) even if the musical peaks would theoretically reach 50W as the clipping of those peaks doesn't sound 'orrible. With typical solid state gear clipping sounds much more objectional, so to achieve a 5W average output you will probably need a 30W amp to sound OK. With a T amp clipping seems even less nice so to achieve 5W output and cope with 50W peaks you are well advised to have a 50W amp. If you tend to listen to continuous compressed high SPL music where the peak and average levels are much closer together you can ignore everything I am saying.

That said the T1 is likely to do fine. It is just that the cost of increasing power is not all that high, doesn't do any harm, and the T4 really has had some nice comments from its users. Now I'm going to don me asbestos undies 'cos the above load of personal opinion is probably going to attract some adverse comment

[goosewing]

@goosewing: You're suggesting higher watt amps such as the T4 and the L20D, which both more than exceeds my power requirements. Is the general rule that the more watts in class-d the better the sound? And although I wouldn't utilise the extra power of such amps, would I still gain something from choosing e.g. the T4 or L20D over the T1?[/QUOTE]

I wouldn't presume to give a definitive answer here but no I don't think there is a correlation between power and sound quality and a small high quality T amp in the right environment and paired with the right speakers should be able to give the larger amps a run for their money.

So why have I been suggesting the higher powered amps? Three things really, your speakers aren't very efficient, buying higher power T amps doesn't incur the same financial penalty as going up in power with class A or AB amps does and lastly there seems to be opinions that clipping is not particularly nice in T amps. i.e. if you have a good 10W class A tube amp it may still sound good even if it is driven in to clipping. This means it can delivery an average power output of 5W (which would give very decent sound levels with moderately efficient speakers) even if the musical peaks would theoretically reach 50W as the clipping of those peaks doesn't sound 'orrible. With typical solid state gear clipping sounds much more objectional, so to achieve a 5W average output you will probably need a 30W amp to sound OK. With a T amp clipping seems even less nice so to achieve 5W output and cope with 50W peaks you are well advised to have a 50W amp. If you tend to listen to continuous compressed high SPL music where the peak and average levels are much closer together you can ignore everything I am saying.

That said the T1 is likely to do fine. It is just that the cost of increasing power is not all that high, doesn't do any harm, and the T4 really has had some nice comments from its users. Now I'm going to don me asbestos undies 'cos the above load of personal opinion is probably going to attract some adverse comment

[soren5]

Originally Posted by goosewing

So why have I been suggesting the higher powered amps? Three things really, your speakers aren't very efficient, buying higher power T amps doesn't incur the same financial penalty as going up in power with class A or AB amps does and lastly there seems to be opinions that clipping is not particularly nice in T amps. i.e. if you have a good 10W class A tube amp it may still sound good even if it is driven in to clipping. This means it can delivery an average power output of 5W (which would give very decent sound levels with moderately efficient speakers) even if the musical peaks would theoretically reach 50W as the clipping of those peaks doesn't sound 'orrible. With typical solid state gear clipping sounds much more objectional, so to achieve a 5W average output you will probably need a 30W amp to sound OK. With a T amp clipping seems even less nice so to achieve 5W output and cope with 50W peaks you are well advised to have a 50W amp. If you tend to listen to continuous compressed high SPL music where the peak and average levels are much closer together you can ignore everything I am saying.

Thanks for this very interesting explanation. I’ve tried both low-powered tube and class-t before (miniwatt N3 and 41Hz Amp6 on more efficient speakers) and you’re completely right about the differences in how the behave when clipping. So I guess it would make sense to increase the power. I’ll follow your advice and get myself a couple of HifimeDiy amps.

I still have a few questions though

1. I need two amps to bi-amp, but could these be connected to the same power supply? Or is it better to keep them separate?
   
   
2. I’ll buy amps, smps(s), enclosure(s), plugs, and wire. Is there something else I’m missing to complete the setup?
   
   
3. Lastly, when bi-amping with e.g. the T1s or T4s, would you then recommend horizontal or vertical bi-amping? The room is so small that the advantage of shorter cables when using a single amp per speaker (vertical) should be negligible. But are there other differences between these two options that I should be aware of?

Thanks again

[goosewing]

Originally Posted by soren5

Thanks for this very interesting explanation.

I'd prefre to call it opinion rather than explanation

I’ve tried both low-powered tube and class-t before (miniwatt N3 and 41Hz Amp6 on more efficient speakers) and you’re completely right about the differences in how the behave when clipping. So I guess it would make sense to increase the power. I’ll follow your advice and get myself a couple of HifimeDiy amps.

I still have a few questions though

1. I need two amps to bi-amp, but could these be connected to the same power supply? Or is it better to keep them separate?

If you are going to connect multiple T amps to the same supply I wouild sugest asking the manufacturer to see if this will work OK, it seems there are interference problems with some models when supplies are shared. If you are going to use a couple of stereo modules bulding them as separate amps each with its own supply seems an obvious answer to retain flexibility and channel separation, if you are going for the four mono amps such as the L20d ones buying four powere supplies might not be so attractive.

2. I’ll buy amps, smps(s), enclosure(s), plugs, and wire. Is there something else I’m missing to complete the setup?

Fairy dust, snake oil, pre-amp, huge box of substitute capacitors made from precious metals lovingly rolled between a maiden's thighs?

3. Lastly, when bi-amping with e.g. the T1s or T4s, would you then recommend horizontal or vertical bi-amping? The room is so small that the advantage of shorter cables when using a single amp per speaker (vertical) should be negligible. But are there other differences between these two options that I should be aware of?

I suspect if your power supplies are good enough it won't make a whole lot of difference. But if you construct as two independent two channel amps you can have the fun of listeneing both ways and seeing which you prefer.

Thanks again

You're welcome.

[soren5]

I finally placed an order for a pair of T1s with the SMPS300Rs. Thanks for the help, it was really appreciated! Now I just need a case, some plugs and wires, and of course some audiophile fairy dust and a bit snake oil to smooth things out – thanks for that tip goosewing

These will be my first DIY amps so it might take a while before I’m done assembling everything. But I promise that once I finish the project I’ll post some pictures.