[R. Daneel]

Hi folks!

I am thinking of purchasing a BP-26 or some other preamplifier. I already own a BHA-1 headphone amplifier and a BDA-2 D/A converter. The hassle is, I really love the BHA-1 and have noticed quite significant improvements in audio quality when it is connected to the BDA-2 with balanced XLR cables so I would really like to keep it connected this way. However, I would also like to have the preamplifier connected this way but since BDA-2 doesn't have two pairs of balanced XLR outputs (like all other DACs), I will no doubt run into a problem.

I intend to have a dedicated music room so the system will be accessible and cables will be easily disconnected and reconnected but I would really prefer not to do this as it wears out the connectors.

I also assume that splitting cables (with one connector on one end and two on the other end) exhibit transmission loss. I could be wrong though.

So, the only remaining option is to get a device that has an input and multiple outputs. Would you recommend a device like this and does Bryston make one?

Cheers!
Antun

[srb]

To my knowledge Bryston does not make a line level switcher.  Although I'm sure there are less expensive ones to be found, one high quality switcher would be the Goldpoint SW2X-0.

 

 

Steve

[R. Daneel]

To my knowledge Bryston does not make a line level switcher.  Although I'm sure there are less expensive ones to be found, one high quality switcher would be the Goldpoint SW2X-0.

 

 

Steve

Hi Steve!

This is EXACTLY what I need!! Thank you very much!!!

I have one question though - this Goldpoint should be a passive device then, right? No power supply is required.

Best wishes,
Antun

[srb]

I have one question though - this Goldpoint should be a passive device then, right? No power supply is required.

Yes, just jacks, wiring and switch.

I couldn't find a photo of the interior of this particular model, but the construction would look similar to this SA1X passive volume control with with a selector switch instead of a stepped attenuator and 6 jacks instead of 4.

 

Steve

[95Dyna]

I've been trying to think of a solution for this as well and was barking up the preamp with balanced fixed output tree to send to the BHA-1 since the BP26 only has one variable output balanced out. The ARC Ref 5 and LS27 were the only two I could find representing a large expenditure to replace the BP 26.

So, just to confirm what you are saying, I can keep my balanced connection from my Esoteric K-05 > BP26 then connect the balanced output from BP26 to the input on the Goldpoint then out to BHA-1 and 7B SST2's. correct?  And you are saying the Goldpoint is of good quality and won't compromise sound quality vs. direct connect from the BP26?

Thanks,

Bill

[R. Daneel]

Yes, just jacks, wiring and switch.

I couldn't find a photo of the interior of this particular model, but the construction would look similar to this SA1X passive volume control with with a selector switch instead of a stepped attenuator and 6 jacks instead of 4.

 

Steve

Superb Steve! Thanks a lot!

I was just reading about these passive preamps... Would something like this work in-between the BDA-2 and a power amp for instance? I suspect the performance would be heavily dependent on the BDA-2 output capability to drive a power amp directly, right?

I will have to consider the Goldpoint switch. I really wouldn't like to degrade the audio quality.

CHeers!
Antun

[srb]

I was just reading about these passive preamps... Would something like this work in-between the BDA-2 and a power amp for instance? I suspect the performance would be heavily dependent on the BDA-2 output capability to drive a power amp directly, right?

Are you thinking of possibly eliminating the BP-26 and and using a switch to go direct to power amp for speakers and to the BHA-1 for headphones with only a single source (BDP-2)?

If so, the Goldpoint units are not remote controlled, so you would lose remote volume feature with the speaker setup.  You could test the BDA-2 direct to power amp if you have a way to digitally attenuate the source.  I don't know if the Bryston or 3rd party software for the BDP-2 offers volume control, or you could temporarily try a PC or Mac as a source into the BDA-2 using the computer system volume control.

It wouldn't be an exact apples for apples comparison because you would be using digital volume control versus analog volume control, but it would let you see if the BDA-2 would properly drive the power amp and what might or might not be missing when eliminating the BP-26 active gain stage.

In either case you would want to be VERY CAREFUL and be sure that the source is properly digitally attenuated so you don't accidentally unleash the full fury of the power amp to your speakers.  There's a certain sense of safety when you have a good analog potentiometer or stepped attenuator in the middle, knowing that a random software glitch or static discharge won't accidentally put you to full volume!

If I'm reading this possible scenario correctly then the Goldpoint SA2X-0 would combine the switcher and a stepped attenuator.  But if you need remote volume or need to accommodate multiple sources, a more full-featured passive "preamp" would be required.

Steve

[brucek]

I also assume that splitting cables (with one connector on one end and two on the other end) exhibit transmission loss. I could be wrong though.

Cheers!
Antun

You can split this signal without too much concern. Typical solid state equipment enjoy output impedances of under 100 ohms and input impedance's from 10K to 50K ohms.

This line level connection is a low level, high impedance connection where almost no current is drawn and you want to present a relatively low line level voltage to the next stage input with as low a noise floor as possible. You're not concerned with power transfer here - the D/A converter acts as a voltage source to the next stage.

Since the split signals are in parallel, they remain the same voltage and since the current is quite low as a result of the rather large impedance mismatch between the D/A output (typically 100 ohms) and the next stage input (typically 10K to 50K), you may split the signal without a noticeable change in volume or signal quality.

I don't particularly like inserting a switcher in the signal path as suggested - too many contacts to cause problems. Far better to use a set of XLR splitter cables.

brucek

[maplegrovemusic]

The Golpoint are made with the intended buyer's being studios . There they would want to switch speakers on the fly for comparisons on say a mix. Therefore i would surmise they should have no signal degradation to your ears . They are not expensive so just buy one and listen for yourself .

[JRace]

...since BDA-2 doesn't have two pairs of balanced XLR outputs (like all other DACs), I will no doubt run into a problem.Antun

Wondering, which DACS have dual balanced outputs?

[srb]

Wondering, which DACS have dual balanced outputs?

Right.  I'm not saying it doesn't exist but I don't think I have ever seen one.

Steve

[R. Daneel]

Are you thinking of possibly eliminating the BP-26 and and using a switch to go direct to power amp for speakers and to the BHA-1 for headphones with only a single source (BDP-2)?

If so, the Goldpoint units are not remote controlled, so you would lose remote volume feature with the speaker setup.  You could test the BDA-2 direct to power amp if you have a way to digitally attenuate the source.  I don't know if the Bryston or 3rd party software for the BDP-2 offers volume control, or you could temporarily try a PC or Mac as a source into the BDA-2 using the computer system volume control.

It wouldn't be an exact apples for apples comparison because you would be using digital volume control versus analog volume control, but it would let you see if the BDA-2 would properly drive the power amp and what might or might not be missing when eliminating the BP-26 active gain stage.

In either case you would want to be VERY CAREFUL and be sure that the source is properly digitally attenuated so you don't accidentally unleash the full fury of the power amp to your speakers.  There's a certain sense of safety when you have a good analog potentiometer or stepped attenuator in the middle, knowing that a random software glitch or static discharge won't accidentally put you to full volume!

If I'm reading this possible scenario correctly then the Goldpoint SA2X-0 would combine the switcher and a stepped attenuator.  But if you need remote volume or need to accommodate multiple sources, a more full-featured passive "preamp" would be required.

Steve

Hi Steve!

Yes, I was thinking perhaps I don't need an active preamp but could do with a passive one. Once I read that there is no preamp like no preamp. In other words, the fellow who said it implied that preamps can only degrade the audio quality. There is no way for me to verify this. In engineering, simpler things usually work more reliably but they do not always perform better in my experience.

I would not be using a digital volume control. Everything I have read about them suggests they work on lower-bit data reduction and cause degradation. I agree that an analogue volume control is much more secure and provides a sense of security.

Would I be right to assume that a passive preamp like the Goldpoint would perform better than an active one, like the BP-26, or is this something of a utopia?

I don't even need the switch that Goldpoint provides but if I bought it, it would be useful to have it.

Cheers!
Antun

[R. Daneel]

You can split this signal without too much concern. Typical solid state equipment enjoy output impedances of under 100 ohms and input impedance's from 10K to 50K ohms.

This line level connection is a low level, high impedance connection where almost no current is drawn and you want to present a relatively low line level voltage to the next stage input with as low a noise floor as possible. You're not concerned with power transfer here - the D/A converter acts as a voltage source to the next stage.

Since the split signals are in parallel, they remain the same voltage and since the current is quite low as a result of the rather large impedance mismatch between the D/A output (typically 100 ohms) and the next stage input (typically 10K to 50K), you may split the signal without a noticeable change in volume or signal quality.

I don't particularly like inserting a switcher in the signal path as suggested - too many contacts to cause problems. Far better to use a set of XLR splitter cables.

brucek

Hi Brucek!

So in your opinion, I should have a look at the splitting cables? Can you please point me to a link where I might take a look at one?

If I understood you correctily, the voltage would remain the same, the current would drop to half and as a result, the impedance would double. But because there is a significant difference between the output impedance and input impedance of the two connected components, this should not make an audible difference. Is this correct?

That makes sense to me. The hassle is, it would require a whole new cable system and would render what I already have useless. I suppose it would depend on how high the quality of the splitting cable is.

Cheers!
Antun

[R. Daneel]

Right.  I'm not saying it doesn't exist but I don't think I have ever seen one.

Steve

Apart from some multi-channel DACs, I haven't seen one either.

[Tezza009]

I hope I haven't missed the point but have you thought of using the BHA-1 as the preamp which will provide a full balanced setup. This is what I have done with my setup (BHA, BDP, BDA and 7Bs). I was going to buy the BP 26 until I realised the limitation on balanced outputs but one of the forum members suggested using the BHA instead.

James verified that the sound quality would be the same (cf with BP26) and it provides a lower cost and a lean setup. There are disadvantages, the BHA does not provide the input / output flexibility of the BP26 (not an issue for me), no remote control (an issue) and the gain is very high requiring careful use of the volume control. The BHA also drives the headphones and speakers in parallel so you need to turn off the 7Bs if using the headphones and unplug the headphones if using the 7Bs.

So not ideal but workable until the BP27 comes out with more balanced outputs (which I think is more likely than the BDA getting this upgrade). I have no idea when a BP27 is due - it could be a long wait ...

Hope this helps.

[R. Daneel]

I hope I haven't missed the point but have you thought of using the BHA-1 as the preamp which will provide a full balanced setup. This is what I have done with my setup (BHA, BDP, BDA and 7Bs). I was going to buy the BP 26 until I realised the limitation on balanced outputs but one of the forum members suggested using the BHA instead.

James verified that the sound quality would be the same (cf with BP26) and it provides a lower cost and a lean setup. There are disadvantages, the BHA does not provide the input / output flexibility of the BP26 (not an issue for me), no remote control (an issue) and the gain is very high requiring careful use of the volume control. The BHA also drives the headphones and speakers in parallel so you need to turn off the 7Bs if using the headphones and unplug the headphones if using the 7Bs.

So not ideal but workable until the BP27 comes out with more balanced outputs (which I think is more likely than the BDA getting this upgrade). I have no idea when a BP27 is due - it could be a long wait ...

Hope this helps.

Hi!

Yes, I have considered this but as you say, there are limitations to using the BHA-1. The main problem for me is that I am a frequent headphone user and the BHA-1 has no headphone/preamp selector switch so you have to unplug the headphones when using the speakers and vice versa. I don't like unplugging cables.

The remote control isn't really a problem for me but the number of inputs on the BHA-1 might be since I have several analogue sources that have to be connected. BHA-1 would be a workable solution for me but ultimately, I would need a dedicated preamp.

Also, can you point me to the place where James stated that BHA-1 is as good of a preamp as BP-26. I would really like to read it because I have read elsewhere that BP-17 and BP-26 are better. I have a feeling the differences would be slight anyway.

Cheers!
Antun

[Tezza009]

There is thread titled upgrade advice that I started 10 October 2014. I don't know how to link - sorry. With the separate power supply for the BP 26 there must be some advantage but my understanding is that the sound from the  BHA is reference quality and the same quality. Perhaps others can comment.

I to have multiple sources but not analogue so have been able to use the digital inputs on the BDA to connect these. I don't see the BHA as the long term solution but effective until BP27 comes out. Of course Bryston cannot pre announce products but we both know that they are very responsive to customer feedback. Based on what has been discussed on this forum I feel confident that a suitable upgrade will happen in a reasonable time frame. Indeed if they simply upgraded the BP26 with the additional balanced outputs then I would buy immediately - as well as a remote !

[brucek]

Yes, I was thinking perhaps I don't need an active preamp but could do with a passive one. Once I read that there is no preamp like no preamp. In other words, the fellow who said it implied that preamps can only degrade the audio quality.

Passive preamps have their place, but they can affect the signal quality far worse than an active preamp. I suspect you'd be disappointed.
The passive preamp has no ability to impedance match the source to its output device. The result in a nutshell is a loss of dynamics.
Additionally, with an passive preamp you have to pay particular attention to cable capacitance or you'll notice the low pass filter that develops (you lose highs).

I should have a look at the splitting cables? Can you please point me to a link where I might take a look at one?

Lots to choose from. Blue Jeans Balanced Cables is one of many.

But because there is a significant difference between the output impedance and input impedance of the two connected components, this should not make an audible difference. Is this correct?

Basically yes. With each split, the impedance that the preamp sees will be reduced. If you are feeding two devices with input impedances of 50Kohms, the source will see 25Kohms.....and so on as you continue to split. With an output impedance in the order of ~100 ohms, it's insignificant to split that signal once. You are also increasing the capacitance that the preamp has to deal with each time you add another long cable in parallel. Again, it's fairly insignificant, and orders of magnitude less significant than adding a passive preamp.

brucek

[JRace]

There is thread titled upgrade advice that I started 10 October 2014. I don't know how to link - sorry.

You find your post, copy the URL from the address bar and paste it in the reply

http://www.audiocircle.com/index.php?topic=129365.msg1367496#msg1367496

[R. Daneel]

Passive preamps have their place, but they can affect the signal quality far worse than an active preamp. I suspect you'd be disappointed.
The passive preamp has no ability to impedance match the source to its output device. The result in a nutshell is a loss of dynamics.
Additionally, with an active preamp you have to pay particular attention to cable capacitance or you'll notice the low pass filter that develops (you lose highs).

Lots to choose from. Blue Jeans Balanced Cables is one of many.

Basically yes. With each split, the impedance that the preamp sees will be reduced. If you are feeding two devices with input impedances of 50Kohms, the source will see 25Kohms.....and so on as you continue to split. With an output impedance in the order of ~100 ohms, it's insignificant to split that signal once. You are also increasing the capacitance that the preamp has to deal with each time you add another long cable in parallel. Again, it's fairly insignificant, and orders of magnitude less significant than adding a passive preamp.

brucek

Hi Brucek!

I was wondering if a passive preamp which is still a lot more affordable than a conventional preamp would be a good solution but as always, things do not get more affordable.

I heave heard of Blue jeans cables on Audioholics and they seem satisfied with them. The link you provided also contains balanced AES/EBU digital cables and one of them is made by Belden which is what Bryston uses as well. Blue jeans sells it for 26$ / 3ft. I paid more, much more.

So in a nutshell, I will need an active preamp and the splitting cable will be a good solution with no loss of audio quality, right?

Cheers!
Antun